Medical gas conduit

Abstract

A medical gas conduit includes an elongated tube that can be formed of a gas permeable material. The medical gas conduit includes one or more features to inhibit ballooning or to improve one or more of crush resistance or crush recovery of the elongated tube. The medical gas conduit can include a reinforcing member. The medical gas conduit can be tethered to another medical gas conduit by a plurality of retainers. The elongated tube can have an improved corrugated profile. The medical gas conduit can include a membrane formed of a gas permeable material. The elongated tube can be formed of a composite material.

Description

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 589,526, filed on October 11, 2023, entitled “MEDICAL GASES CONDUIT”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to a medical gas conduit for delivering medical gases in a medical gas system. More specifically, but not entirely, this disclosure relates to a medical gas conduit comprising a breathable material permeable to water molecules, for use in a respiratory support system, an anesthetic respiratory system, or a surgical insufflation system. Background Technology

[0003] Depending on the source (e.g., ambient air, compressed gas cylinders, or hospital supply), the temperature of the medical gas received by the medical gas system may be below about 25 degrees Celsius (°C), below about 20°C, or below about 15°C; and the relative humidity may be less than about 50%, less than about 25%, less than about 10%, or less than about 5%.

[0004] Heating and / or humidifying the medical gas stream supplied to patients may provide clinical benefits.

[0005] In respiratory support systems or anesthetic respiratory systems, it may be beneficial to heat and humidify the respiratory gas flow to simulate the temperature and humidity naturally present in the lungs of a healthy person, which may be approximately 37 degrees Celsius (°C) and / or 100% relative humidity. The respiratory gas flow can be heated and / or humidified to approximate or reach these levels.

[0006] In surgical air-blowing systems, heating and humidifying the airflow supplied to the patient's abdomen or peritoneal cavity can be beneficial, for example, during laparoscopic surgery. Heating and / or humidifying the airflow can reduce cell damage or dehydration, limit adhesion formation, or reduce other harmful effects.

[0007] In a medical gas system, a flow of medical gas can be delivered to and / or from a patient via one or more conduits.

[0008] The catheter may have a wall that defines an inner lumen for the passage of medical gases. For example, the temperature of the wall may be affected by one or more of the following: the temperature of the ambient air, the movement of the ambient air, sunlight on the wall, or any bedding placed on the catheter.

[0009] The temperature difference between the medical gas and the tube wall can cause the medical gas flow to cool as it travels along the length of the tube. If the temperature of the medical gas drops to its dew point, the water vapor in the medical gas may condense into liquid water, thus forming condensate inside the cavity.

[0010] In some examples, such as in a hospital environment, one or more of the ambient air temperature or humidity may be regulated (e.g., by a heating, ventilation, and air conditioning (HVAC) system). In other examples, such as in a patient's home, one or more of the ambient air temperature and humidity may be unregulated and may fluctuate during the day and / or with the seasons.

[0011] Alternatively or additionally, condensation may form in other components of the medical gas system upstream or downstream of the duct. For example, in a respiratory support system, respiratory gases delivered to a ventilator or anesthesia machine via an expiratory duct may cause condensation to form within the ventilator or anesthesia machine. Condensation may accumulate in filters or on flow sensors within the ventilator or anesthesia machine.

[0012] In addition, condensate or other liquids may drain into the catheter from other components of the medical gas system, such as filters, nebulizers, Y-shaped fittings, intubation connectors, or patient interfaces.

[0013] Condensation or other liquids in conduits or other components of a medical gas system can cause a variety of problems, such as one or more of the following: Sensor reading error; Filter saturation; Alarms (e.g., auditory and visual); The ventilator, anesthesia machine, or its components (e.g., flow sensor) are damaged; Regular drainage is required; or The flow path is blocked. Summary of the Invention

[0014] In a first aspect, a medical gas circuit kit for delivering a flow of medical gas in a medical gas system may include: an inlet conduit; an outlet conduit configured to be fluidly coupled to the inlet conduit, at least a portion of the outlet conduit being configured to expand more than the inlet conduit in at least a longitudinal direction during use; and a plurality of retainers, each of the plurality of retainers being configured to retain a portion of the inlet conduit and a portion of the outlet conduit to tether the outlet conduit to the inlet conduit, the plurality of retainers being configured in conjunction with the inlet conduit to inhibit expansion of at least a portion of the outlet conduit in the longitudinal direction during use.

[0015] In a second aspect, a medical gas circuit kit for delivering a flow of medical gas in a medical gas system may include: an inlet conduit; an outlet conduit, the outlet conduit including a breathable material; and a plurality of retainers, each of the plurality of retainers including a pair of retaining members, one of the retaining members being configured to receive and retain a portion of the inlet conduit, and the other retaining member being configured to receive and retain a portion of the outlet conduit to tether the outlet conduit to the inlet conduit.

[0016] The following optional features apply to each of the first aspect and the second aspect.

[0017] The plurality of retainers may include: at least 2 retainers; at least 3 retainers; 2 to 120 retainers; 3 to 60 retainers; 4 to 40 retainers; or one retainer for every 4 to 50 corrugations of the outlet conduit.

[0018] The plurality of retainers can be configured to engage with the inlet conduit at a plurality of discrete locations along the length of the inlet conduit; and / or engage with the outlet conduit at a plurality of discrete locations along the length of the outlet conduit.

[0019] At least one of the plurality of retainers may be configured to suppress radial expansion of the outlet conduit during use by surrounding at least a majority of its circumference.

[0020] During use, the absorption of water molecules by the outlet conduit can cause the outlet conduit to expand radially between consecutive pairs of retainers among the plurality of retainers.

[0021] The multiple retainers can each be configured to hold corresponding portions of the inlet conduit and the outlet conduit in a side-by-side arrangement.

[0022] The plurality of retainers may each be configured to keep corresponding portions of the inlet conduit and the outlet conduit substantially adjacent to each other, such that the outlet conduit is at least partially heated by the inlet conduit during use.

[0023] The plurality of retainers may each be configured to engage with one or more of the following: the inlet conduit to inhibit movement along the length of the inlet conduit; and / or the outlet conduit to inhibit movement along the length of the outlet conduit.

[0024] The inlet conduit may include a plurality of corrugations, each of the plurality of retainers being configured to engage with one or more of the plurality of corrugations of the inlet conduit; and / or the outlet conduit may include a plurality of corrugations, each of the plurality of retainers being configured to engage with one or more of the plurality of corrugations of the outlet conduit.

[0025] The plurality of retainers may each include: a first clamp configured to be detachably fitted around the portion of the inlet conduit; and a second clamp configured to be detachably fitted around the portion of the outlet conduit.

[0026] The first clamp may be partially annular and define an opening through which the inlet conduit is detachably received; and / or the second clamp may be partially annular and define an opening through which the outlet conduit is detachably received.

[0027] One or more of the plurality of retainers may be configured to be connected to one or more other retainers via a mechanical connection.

[0028] The mechanical connection may include one or more of the following: snap-fit ​​connection; pivotable connection; or ball-and-socket connection.

[0029] Each of the plurality of retainers may include: a first connector; and a second connector configured to establish a mechanical connection with the first connector of another retainer among the plurality of retainers.

[0030] The plurality of retainers may each include an arm, and: the distal end of the arm may include the first connector; and / or the proximal end of the arm may include the second connector.

[0031] The first connector may include a ball connector, and the second connector may include a socket, the ball connector being configured to establish a ball-socket connection with the socket of another retainer among the plurality of retainers, and / or the socket being configured to establish a ball-socket connection with the ball connector of another retainer among the plurality of retainers.

[0032] These multiple retainers can each be essentially identical.

[0033] Each of the plurality of retainers may, for example, be integrally formed from a polymer material.

[0034] The inlet conduit may include a heater (e.g., a heating wire).

[0035] The plurality of retainers may each be configured to: suppress radial expansion of the portion of the outlet conduit when the outlet conduit is in one or more of an adjustment state or a saturation state; and / or not suppress radial expansion of the portion of the outlet conduit when the outlet conduit is in one or more of a dry state or a balanced state.

[0036] The length of the outlet conduit in a balanced state can be between about 0.8 meters (m) and 2.5 meters, and optionally: between about 0.8 meters and 1.4 meters, or between about 1.0 meters and 1.4 meters, for example, about 1.2 meters; or between about 1.2 meters and 2.0 meters, or between about 1.4 meters and 1.8 meters, for example, about 1.6 meters.

[0037] The medical gas circuit kit may exclude at least one of the following, and optionally two of the following: a heater (e.g., a heating wire or a water jacket) configured for use with the outlet conduit; or a water collector configured for use with the outlet conduit.

[0038] The outlet conduit may include an elongated tube comprising a breathable material that, in use, expands in one or more of the radial or longitudinal directions due to the absorption of water molecules.

[0039] The breathable material may include a block polymer, which optionally includes one or more of the following: polybutylene terephthalate hard segments; or polyether-type macromolecular diol soft segments.

[0040] The outlet conduit may include an elongated tube configured to absorb at least 33%, about 33% to 200%, about 100% to 160%, about 120% to 140%, or about 130% to 135% (e.g., 133%) of its own mass of water molecules during an immersion test.

[0041] The outlet conduit may include an elongated tube configured to expand at least one of the radial or longitudinal directions during an immersion test, and optionally each expansion by at least 20%, about 20% to 70%, about 25% to 50%, or about 30% to 50%.

[0042] The medical gas circuit kit can be a breathing circuit kit, the medical gas system can be a breathing assist system, the inlet tube can be an inspiratory tube, and the outlet tube can be an expiratory tube.

[0043] The medical gas circuit kit may also include one or more of the following: a humidifier supply tubing; a pressure reducing valve; a humidification chamber; a Y-shaped fitting; a cannula connector; a patient interface; a catheter holder; a filter; or a pressure regulator.

[0044] The medical gas circuit kit can be an anesthesia breathing circuit kit, the medical gas system can be an anesthesia breathing system, the inlet tube can be an inspiratory tube, and the outlet tube can be an expiratory tube.

[0045] The medical gas circuit kit can be a surgical inhalation circuit kit, the medical gas system can be a surgical inhalation system, the inlet catheter can be a delivery catheter, and the outlet catheter can be a discharge catheter.

[0046] Other technical features will be apparent to those skilled in the art from the following description, claims and drawings.

[0047] In a third aspect, a medical gas conduit for delivering a flow of medical gas in a medical gas system may include: an elongated tube defining an inner lumen through which the medical gas flow passes, at least a portion of the elongated tube comprising a breathable material configured to expand due to the absorption of water molecules during use; a pair of connectors disposed at respective ends of the elongated tube, the pair of connectors being configured to pneumatically couple the medical gas conduit to other components of the medical gas system; and a reinforcing member configured to engage the elongated tube at least along its length at a plurality of discrete locations between the pair of connectors, the reinforcing member being configured to: prevent at least a portion of the elongated tube from expanding in one or more of a radial or longitudinal direction; and / or improve at least a portion of the medical gas conduit in one or more of a crush resistance or crush recovery.

[0048] The reinforcing member can be securely attached to the pair of connectors.

[0049] The reinforcing member may be located at least partially within the inner cavity of the elongated tube.

[0050] The reinforcing member may include a helical shape.

[0051] The reinforcing member can be securely attached to the elongated tube at one or more locations along the length of the elongated tube between the pair of connectors.

[0052] The reinforcing member can be securely attached to one or more of the connectors in the pair or to the corresponding end of the elongated tube.

[0053] The reinforcing member can be configured to: bias the elongated tube to a predetermined length, which is optionally approximately equal to the length of the elongated tube in a balanced state; and / or, in use, be in a tensioned state when the elongated tube is in an adjustable state.

[0054] The reinforcing member may be formed at least in part from one or more of the following: a malleable alloy material; and / or a polymer material, such as polypropylene.

[0055] The reinforcing member can be configured to wick condensate or other liquids from the cavity during use.

[0056] The reinforcing member may include one or more grooves configured to at least partially wick the condensate or other liquid through capillary action.

[0057] The reinforcing member may include a longitudinal portion and a plurality of radial portions, each of the plurality of radial portions extending outward from the longitudinal portion and configured to engage with a corresponding portion of the elongated tube or the pair of connectors.

[0058] The longitudinal portion may be located at the center of the cavity or around the center of the cavity.

[0059] The elongated tube may be corrugated, and one or more of the plurality of radial portions may be configured to engage with the corresponding corrugations of the elongated tube, for example, by friction fit or interference fit.

[0060] The reinforcing member may be located at least partially outside the elongated tube, for example, substantially concentric around the elongated tube.

[0061] The reinforcing member may include a double helix structure.

[0062] The reinforcing member may include a hollow structure.

[0063] The hollow structure can be formed at least partially from an elastomeric material.

[0064] The hollow structure may include: a plurality of annular members arranged substantially coaxially and spaced apart along at least a portion of the length of the elongated tube; and a plurality of longitudinal members, each extending between corresponding consecutive pairs of the plurality of annular members.

[0065] The elongated tube may be corrugated, and one or more of the plurality of annular members may be configured to engage with the corresponding corrugation of the elongated tube when the medical gas conduit is in a balanced or regulated state.

[0066] The plurality of longitudinal members can be rotatably biased between two or more consecutive pairs of the plurality of annular members.

[0067] The hollow structure may be formed, at least in part, from one or more of the following: polymeric materials, such as polypropylene; and / or malleable alloys.

[0068] The reinforcing member can be formed, at least in part, from a shape memory material.

[0069] The reinforcing member can be configured to deform in response to temperature changes in the slender tube during use.

[0070] The reinforcing member can be plastic.

[0071] The reinforcing member may include a sheath, wherein the sheath is not a woven sheath.

[0072] The sheath can be configured to at least partially conform to the outer surface of the slender tube when the medical gas conduit is in equilibrium.

[0073] The slender tube may be corrugated, and the sheath may be configured to conform to the outer crest of the outer surface of the slender tube when the medical gas conduit is in equilibrium.

[0074] The reinforcing member can be embedded inside the slender tube.

[0075] Other technical features will be apparent to those skilled in the art from the following description, claims and drawings.

[0076] In a fourth aspect, a medical gas conduit for delivering a flow of medical gas in a medical gas system may include: a membrane comprising a breathable material configured to expand due to the absorption of water molecules during use; and an elongated tube: arranged substantially concentrically relative to the membrane; fixedly attached to the membrane at a plurality of discrete locations along the length of the elongated tube; configured to support the membrane; configured to be permeable to water molecules; and configured to inhibit expansion of at least a portion of the membrane in at least one of a radial or longitudinal direction during use.

[0077] The membrane can at least partially define the cavity for the medical gas flow.

[0078] The elongated tube can be directly attached to the membrane at multiple discrete locations along its length.

[0079] In some examples, the medical gas conduit may not include ribs (e.g., spiral ribs) located between the membrane and the elongated tube.

[0080] The slender tube can be a corrugated slender tube.

[0081] The membrane can be directly attached to the outer wave peak outside the corrugated elongated tube or the inner wave peak inside the corrugated elongated tube, and spans between the outer wave peak or the inner wave peak.

[0082] The membrane wall thickness can be less than about 200 micrometers (μm), less than about 100 μm, less than about 80 μm, less than about 60 μm, less than about 40 μm, or about 20 μm.

[0083] The slender tube can be arranged substantially concentrically around the membrane.

[0084] The membrane can be configured to extend between adjacent inner wave peaks on the inner surface of the elongated tube.

[0085] The membrane can form a substantially smooth inner pore in the medical gas conduit.

[0086] The membrane can be arranged concentrically around the slender tube.

[0087] The membrane can be configured to extend between adjacent outer peaks on the outer surface of the tube.

[0088] The slender tube can be porous (e.g., perforated).

[0089] The membrane and the elongated tube may include co-extruded components.

[0090] The membrane and the elongated tube may be made of different materials.

[0091] Other technical features will be apparent to those skilled in the art from the following description, claims and drawings.

[0092] In a fifth aspect, a medical gas conduit for delivering a flow of medical gas in a medical gas system may include an elongated tube, the elongated tube being at least partially formed of a composite material comprising: a polymer matrix; and a reinforcing material.

[0093] The polymer matrix may include breathable materials.

[0094] The composite material may include a fiber-reinforced polymer; and / or the reinforcing material may include a fiber reinforcement.

[0095] The fiber reinforcement may include one or more of the following: synthetic fibers, such as carbon fiber, glass fiber or aramid fiber; or natural fibers, such as cellulose fiber, jute fiber, flax fiber or hemp fiber.

[0096] In one or more of the dry or equilibrium states, the volume fraction of the fiber reinforcement may be about 5% to 60%, about 10% to 50%, about 20% to 40%, or about 30% of the elongated tube.

[0097] The average diameter of the fiber reinforcement can be between approximately 3µm and 20µm.

[0098] The fibers of the fiber reinforcement may include a fiber sizing agent.

[0099] The reinforcing material may include discontinuous fibers.

[0100] The discontinuous fiber may meet one or more of the following criteria: an average length of less than about 25 mm, or less than about 5 mm; an average length of at least 0.5 mm, between about 0.5 mm and 10 mm, or between about 1 mm and 5 mm, for example, about 1.5 mm or about 3 mm; an average diameter between about 5 μm and 30 μm, or between about 10 μm and 20 μm, for example, about 15 μm; or an aspect ratio greater than the critical fiber length of the polymer matrix.

[0101] The discontinuous fibers may be arranged randomly; the discontinuous fibers may be arranged in a circumferential direction; the discontinuous fibers may be arranged in a longitudinal direction; or about 20% to 100% or at most about 80% of the discontinuous fibers may be arranged in the same direction as each other (e.g., in either the circumferential direction or the longitudinal direction).

[0102] The reinforcing material may include continuous fibers, which optionally span one or more of the length or circumference of the elongated tube.

[0103] The continuous fiber may include fabrics, such as woven, knitted, felted, or braided preforms.

[0104] The continuous fibers can be arranged in one or more directions.

[0105] The continuous fiber can be partially embedded in the slender tube.

[0106] In a sixth aspect, a medical gas conduit for delivering a flow of medical gas in a medical gas system may include: an elongated tube defining an inner lumen through which the medical gas flow passes; and a pair of connectors disposed at respective ends of the elongated tube, the pair of connectors being configured to pneumatically couple the medical gas conduit to other components of the medical gas system, the connector in the pair of connectors including a pair of orifices.

[0107] The two orifices can be set with their diameters opposite each other.

[0108] The two orifices can be combined to extend more than 80% of the circumference of the connector.

[0109] The medical gas catheter may include a sheath surrounding the outer surface of the elongated tube.

[0110] The sheath can be a woven sheath.

[0111] The sheath can be exposed through the pair of orifices.

[0112] The sheath can be securely attached to the slender tube via the connector.

[0113] The connector may at least partially overmold onto the sheath and the elongated tube.

[0114] The connector can be formed from two parts.

[0115] The connector may include: a first part, which is injection molded; and a second part, which is overmolded onto the first part.

[0116] The second part may be overmolded onto the first part, the elongated tube, and the sheath, the sheath being disposed around the outer surface of the elongated tube.

[0117] Other technical features will be apparent to those skilled in the art from the following description, claims and drawings.

[0118] The length of the medical gas conduit according to any one of the third to sixth aspects in equilibrium may be between about 0.8m and 2.5m, and optionally: between about 0.8m and 1.4m, or between about 1.0m and 1.4m, for example, about 1.2m; or between about 1.2m and 2.0m, or between about 1.4m and 1.8m, for example, about 1.6m.

[0119] In some examples, the medical gas conduit according to any one of the third to sixth aspects may not include at least one of the following, and optionally include two of the following: a heater (e.g., a heating wire or a water jacket); or a water collector.

[0120] At least a portion of the medical gas conduit according to any one of the third to sixth aspects may include a breathable material, which, in use, is configured to expand in one or more of the radial direction, the longitudinal direction, or the wall thickness due to the absorption of water molecules.

[0121] The elongated tube according to any one of the third to sixth aspects may be configured to absorb at least 33%, about 33% to 200%, about 100% to 160%, about 120% to 140%, or about 130% to 135% (e.g., 133%) of its own mass in an immersion test.

[0122] The elongated tube according to any one of the third to sixth aspects may be configured to expand at least one of the radial direction or the longitudinal direction in an immersion test, and optionally each expands by at least 20%, about 20% to 70%, about 25% to 50%, or about 30% to 50%.

[0123] The breathable material according to any one of the third to sixth aspects may include a block polymer, which optionally includes one or more of the following: polybutylene terephthalate hard segments; or polyether-type macromolecular diol soft segments.

[0124] The medical gas system may be a respiratory support system, and the medical gas conduit according to any one of the third to sixth aspects may be an expiratory conduit configured to deliver respiratory gas from the patient during use.

[0125] The medical gas circuit kit may include a medical gas conduit according to any one of the third to sixth aspects, and any one or more of the following: a humidifier supply conduit; a pressure reducing valve; a humidification chamber; an inhalation conduit; multiple retaining members; a delivery conduit; a Y-shaped member; an insertion connector; a patient interface; a conduit holder; an expiratory conduit; an exhaust conduit; a filter; or a pressure regulator.

[0126] The medical gas system may be an anesthesia respiratory system, and the medical gas conduit according to any one of the third to sixth aspects may be an expiratory conduit configured to deliver respiratory gases from the patient during use.

[0127] The medical gas system may be a surgical inhalation system, and the medical gas conduit according to any one of the third to sixth aspects may be an exhaust conduit configured to deliver inhaled gas from the patient during use.

[0128] Other technical features will be apparent to those skilled in the art from the following description, claims and drawings.

[0129] Other aspects, novel features, and advantages of this disclosure will be apparent to those skilled in the art from any one or more of the illustrative examples set forth in the following detailed description and accompanying drawings. The detailed description and drawings are intended to be illustrative in nature and not restrictive. Modifications or improvements may be made without departing from the spirit or scope of this disclosure and the claims. Attached Figure Description

[0130] To facilitate the identification of any particular element in the discussion, one or more of the highest digits in the figure references refer to the figure number in which the element was first introduced.

[0131] The example is described in further detail below with reference to the accompanying drawings, in which: Figure 1 This is a schematic diagram of an example respiratory support system.

[0132] Figure 2 It can be used Figure 1A schematic diagram of a humidifier for a respiratory support system.

[0133] Figure 3 This is a schematic diagram of an example expiratory cannula in a balanced state.

[0134] Figure 4 It is in a state of adjustment. Figure 3 A schematic diagram of an expiratory duct.

[0135] Figure 5 This is a schematic diagram of another example of an expiratory cannula.

[0136] Figure 6 This is a perspective view of a portion of another example expiratory cannula.

[0137] Figure 7 This is a schematic cross-sectional view of another example expiratory cannula.

[0138] Figure 8 This is a schematic diagram of a portion of another example expiratory cannula.

[0139] Figure 9 This is a side view of another example expiratory cannula.

[0140] Figure 10 This is a schematic diagram of another example of an expiratory cannula in a state of equilibrium.

[0141] Figure 11 yes Figure 10 A schematic diagram of an expiratory duct in an adjustable state.

[0142] Figure 12 This is a schematic diagram of another example of an expiratory cannula.

[0143] Figure 13 This is a schematic diagram of an inspiratory and expiratory duct based on another example.

[0144] Figure 14 This is a detailed schematic diagram of the various parts of an inspiratory tube, an expiratory tube, and multiple retainers, based on another example.

[0145] Figure 15 Is it like this? Figure 14 A detailed schematic diagram of a pair of retainers is shown.

[0146] Figure 16 yes Figure 15 A schematic cross-sectional view of a pair of retainers.

[0147] Figure 17 This is a schematic cross-sectional view of a portion of another example expiratory cannula.

[0148] Figure 18 This is a schematic cross-sectional view of a portion of another example expiratory cannula.

[0149] Figure 19 This is a schematic cross-sectional view of a portion of another example expiratory cannula.

[0150] Figure 20 This is a detailed side view of a portion of another example expiratory cannula.

[0151] Figure 21 This is a detailed schematic cross-sectional view of a portion of another example expiratory cannula.

[0152] Figure 22 This is a schematic partial cross-sectional view of a portion of another example expiratory cannula.

[0153] Figure 23 An example is shown. Figure 22 Detail A.

[0154] Figure 24 An example based on another example is shown. Figure 22 Details B.

[0155] Figure 25 This is shown according to yet another example. Figure 22 Detail A.

[0156] Figure 26 This is a schematic diagram of an example surgical insufflation system. Detailed Implementation

[0157] This disclosure relates to medical gas conduits that can be used in various medical gas systems (including, but not limited to, respiratory support systems, anesthesia respiratory systems, or surgical insufflation systems), as well as medical gas circuits (e.g., breathing circuits, anesthesia breathing circuits, surgical insufflation circuits).

[0158] The following description of various example medical gas catheters is made with particular reference to their use as expiratory catheters in respiratory support systems. However, it should be understood that the example medical gas catheters may be used or modified for use, for example, in alternative medical gas systems, such as as one or more of the following: expiratory catheters in alternative respiratory support systems (e.g., respiratory support systems configured to provide continuous positive airway pressure (CPAP) or bubble CPAP (bCPAP) therapy); one or more inspiratory or expiratory catheters in anesthesia respiratory systems; or exhaust catheters in surgical insufflation systems.

[0159] Options for reducing condensation in the inspiratory and expiratory tubing may include reducing the level of active humidification, or using one or more of insulation, a water collector, or a heater. However, each of these has been found to have at least some drawbacks.

[0160] Lowering the level of active humidification may, in turn, reduce the absolute and / or relative humidity of the medical gases supplied to the patient. However, this may not be optimal for patient comfort or recovery, for example, when bypassing the patient's upper airway during invasive ventilation. It also may not necessarily address condensation or other liquids that form in or drain from the catheter (e.g., from the patient or other components of the medical gas system).

[0161] Insulating catheters can reduce the rate of heat loss as medical gases travel along their length. For example, the catheter may be fitted with an insulating jacket or have air gaps in its wall. However, such insulation may increase one or more of the catheter's diameter, weight, and cost; impair its flexibility; or have limited effectiveness. Insulation also cannot handle condensation that may drain into the catheter from another component of the medical gas system.

[0162] A collector collects accumulated condensate and other fluids for disposal. However, the collector's location is fixed and may not necessarily coincide with the lowest point of the tubing where condensate may accumulate during use. Healthcare professionals may need to periodically manipulate the tubing by lifting different sections to direct accumulated condensate toward and into the collector. For example, if mishandled, this could result in some condensate being discharged simultaneously to the patient or ventilator, and condensate may become trapped within the tubing's corrugations. Furthermore, the increased weight of the collector and the collected condensate can increase tubing resistance, and the collector may need to be emptied periodically. This could interrupt treatment for the patient and pose an infection risk. A collector addresses this issue to some extent once condensation occurs. It can also handle condensate or fluids from other components of the ventilator to some degree. However, it does not fundamentally solve the problem and has its own drawbacks.

[0163] The heater is designed to maintain or increase the temperature of the breathing gas above its dew point. This reduces the formation of condensate in the duct. Potential drawbacks of the heater leads may include one or more of the following: An electrical connection needs to be established between the conduit and the power source (e.g., humidifier 102); This increases the complexity of the heating and humidification algorithms; The temperature and absolute / relative humidity of the gas received by the ventilator are relatively high; Additional standards specific to heated conductor breathers must be followed (e.g., International Electrotechnical Commission (IEC) 60601-1 (IEC:2005+A1:2012(E)), Section 11.2). Shortened warranty period; and Power consumption during the use of heated conduits can contribute to approximately 50% of the total carbon footprint of the heated conduit over its entire lifespan.

[0164] An alternative form of heater is a "water jacket" heater. Heated water or other liquid is circulated through channels located around the conduit. However, this may have one or more of the following further disadvantages: increased conduit size, weight, or cost; the need for water heating and pumping; or a risk of leakage.

[0165] The medical gas conduit according to this disclosure may be at least partially formed of a breathable material. In some examples, the medical gas conduit does not require a reduction in the active humidification level. In some examples, the medical gas conduit does not include one or more of an insulation layer, a water collector, or a heater (e.g., any one of them).

[0166] respiratory support system

[0167] refer to Figure 1 A schematic diagram of an example respiratory support system 100 is shown. The respiratory support system 100 can be configured to provide noninvasive ventilation (NIV) therapy to a patient. In other examples, the respiratory support system 100 can be configured to provide invasive ventilation therapy to a patient.

[0168] Mechanical ventilation can be used in a wide range of applications, from providing supplemental pressure and flow to assist a patient’s spontaneous breathing (“respiratory support”) to providing complete control over each breath (“life support”). Patients receiving mechanical ventilation may be connected to a respiratory support system for more than 24 hours, and, depending on the patient’s condition, for a period of time, months, or even permanently.

[0169] The respiratory support system 100 may include a gas source 104.

[0170] In some examples, the gas source 104 may be an indoor induced draft ventilator. The ventilator may include a pressure generator 106, such as a blower or a positive displacement pump (such as a bellows pump). The pressure generator 106 may be configured to draw ambient air 108 into the gas source 104 through the ambient air inlet 110. The pressure generator 106 may be configured to pressurize the ambient air 108 to generate a breathing gas flow. In some examples, the ambient air 108 may be supplemented with other gases, such as supplemental oxygen (not shown).

[0171] Gas source 104 may include gas source controller 112. Gas source controller 112 may be configured to control the operation of pressure generator 106. In some examples, gas source controller 112 may be configured to control or regulate one or more of the flow rate, pressure, or volume of the breathing gas flow.

[0172] Gas source controller 112 may include one or more processors. Gas source controller 112 may include a machine-readable medium (e.g., non-transitory memory). The machine-readable medium is programmable with instructions that, when executed by one or more processors, cause gas source 104 to operate as described herein. Gas source controller 112 may be configured to control gas source 104 based at least in part on input received from user interface 114. Gas source controller 112 may be configured to control gas source 104 based at least in part on input received from one or more sensors (e.g., one or more of a flow rate sensor or a motor speed sensor). Gas source controller 112 may be configured to control gas source 104 using closed-loop control (e.g., using a proportional-integral-derivative (PID) control algorithm).

[0173] In some examples, gas source 104 may receive pressurized breathing gas from a remote source. For example, gas source controller 112 may control the pressure of the breathing gas flow delivered to the patient by controlling a proportional solenoid valve.

[0174] In some examples, the gas source 104 may be configured to deliver a flow of respiratory gas to an adult patient, for example, at a flow rate of up to 120 liters per minute (l / min) (e.g., in the range of about 30 l / min to 80 l / min).

[0175] In some examples, the gas source 104 may be configured to deliver a flow of respiratory gas to a neonate or pediatric patient, for example, at a flow rate of about 0.5 l / min to 60 l / min. The precise flow rate may depend on one or more of the patient's therapy, age, or weight.

[0176] The gas source 104 can be configured to deliver breathing gas to the patient at a pressure of up to about 6 kPa (about 60 cmH2O). Components of the respiratory support system 100 (e.g., catheters) can be tested and labeled for use at higher pressures, such as about 8 kPa (about 80 cmH2O).

[0177] In another example, the gas source 104 may be an anesthesia machine. For anesthesia applications, the respiratory support system 100 may deliver a mixture of respiratory gases and anesthetic agents to the patient, for example, to administer sedatives and render the patient unconscious for surgery. The anesthetic gas mixture may be delivered to the patient at a flow rate of up to about 20 l / min (or, for some “low-flow” applications, up to about 10 l / min). The anesthetic gas mixture may be delivered at a pressure of up to about 6 kPa. The pressure may be lower than the typical pressure for mechanical ventilation. The anesthesia machine may include a rebreathing system that delivers gas to the patient via an inspiratory tube and returns exhaled gas to the anesthesia machine via an expiratory tube. The anesthesia machine and the breathing circuit typically form a closed loop to prevent leakage of anesthetic agents into the surrounding environment. Patients are typically connected to the anesthesia machine for less than 24 hours. Patients receiving anesthetic agents may be continuously monitored by an anesthesiologist.

[0178] The respiratory support system 100 may include a humidifier supply conduit 116.

[0179] The humidifier supply conduit 116 can be configured to receive a breathing gas flow from the gas source outlet 118 and deliver the breathing gas flow to downstream components of the respiratory support system 100 (e.g., a humidifier).

[0180] The humidifier supply conduit 116 may include a tube. The tube may be flexible. The tube may be corrugated.

[0181] In other examples (e.g., a breathing assist system 100 that omits the humidifier or includes a humidifier integrated with the gas source 104), the humidifier supply conduit 116 may be omitted or replaced by an internal conduit.

[0182] The respiratory support system 100 may include a humidifier 102.

[0183] The humidifier 102 may be configured to heat and / or humidify a stream of breathing gas received from a gas source 104, for example, via a humidifier supply conduit 116.

[0184] Humidifier 102 may be an active permeable humidifier. In some examples, humidifier 102 may be an F&P 810 purchased from Fisher & Paykel Healthcare Limited in Auckland, New Zealand. ™ 820 ™ 850 ™ Or 950 ™ Heated humidifier. In other examples, humidifier 102 may be, for example, a passive (unheated) pass-through humidifier, a heat and moisture exchanger (HME), an atomizing humidifier, or a humidifier that supplies a continuously or periodically controlled flow of humidifying liquid to a heating element to achieve instantaneous or near-instantaneous evaporation.

[0185] The humidifier 102 may include a humidification chamber 120. The humidification chamber 120 may be configured to contain a volume of humidifying liquid (e.g., water). The humidification chamber 120 may include a chamber inlet 122 configured to receive a flow of breathing gas. The humidification chamber 120 may include a chamber outlet 124 configured to supply a heated and humidified flow of breathing gas to downstream components of the breathing assist system 100. The humidification chamber 120 may include a heat conductor, for example, made of aluminum or stainless steel.

[0186] In some examples, the humidification chamber 120 may include a float valve (not shown) for maintaining or replenishing the volume of humidifying liquid (e.g., from a sterile water bag). The humidification chamber 120 may include a water supply line and a water needle for fluid coupling with the sterile water bag.

[0187] The humidifier 102 may include a chamber heater 126. The chamber heater 126 may include a heating element. The humidification chamber 120 may be configured to be detachably coupled to the chamber heater 126, for example, wherein a heat conductor is in physical contact with the chamber heater 126. In use, heat generated by the chamber heater 126 may be conducted through the humidification chamber 120, thereby warming a volume of humidifying liquid. At least a portion of the volume of humidifying liquid may, for example, be vaporized into water vapor. Breathing gases passing through the top space of the humidification chamber 120 may be heated and / or humidified by the volume of humidifying liquid and / or the vaporized humidifying liquid.

[0188] The humidifier 102 may include a humidifier controller 128. The humidifier controller 128 may be configured to control the operation of the humidifier 102. The humidifier controller 128 may be configured to control the temperature of the chamber heater 126. The humidifier controller 128 may be configured to at least partially control one or more of the temperature or humidity of the breathing gas flow.

[0189] The humidifier controller 128 can be configured to at least partially regulate the temperature of the respiratory gas flow such that the respiratory gas received by the patient is at or near a predetermined temperature. In the case of non-invasive ventilation, the humidifier 102 can be configured to deliver a respiratory gas flow to the patient at a temperature of approximately 31°C. In the case of invasive ventilation, the humidifier 102 can be configured to deliver a respiratory gas flow to the patient at a temperature of approximately 37°C.

[0190] The humidifier controller 128 can be configured to at least partially regulate the humidity of the respiratory gas flow such that the respiratory gas received by the patient is at or near a predetermined humidity level. When the patient is receiving non-invasive ventilation, the humidifier 102 can be configured to deliver a respiratory gas flow to the patient at approximately 70% relative humidity. When the patient is receiving invasive ventilation, the humidifier 102 can be configured to deliver a respiratory gas flow to the patient at approximately 100% relative humidity.

[0191] The breathing assistance system 100 (e.g., one or more of the gas source 104, humidifier 102, and / or inhalation duct 130) may include one or more sensors. For example, each of the one or more sensors may be configured to sense one or more of temperature, relative humidity, absolute humidity, flow rate, pressure, or blower speed. For example, a temperature sensor may be configured to sense the temperature of one or more of ambient air 108, chamber heater 126, heat conductor of humidification chamber 120, humidifying liquid, or breathing gas flow.

[0192] Humidifier controller 128 may include one or more processors. Humidifier controller 128 may include a machine-readable medium (e.g., non-transitory memory). The machine-readable medium is programmable with instructions that, when executed by one or more processors, cause humidifier controller 128 to operate as described herein. Humidifier controller 128 may be configured to control humidifier 102 based at least in part on input received from user interface 132. In some examples, one or more of a predetermined temperature or a predetermined humidity may be adjustable by the user. Humidifier controller 128 may be configured to control humidifier 102 based at least in part on input received from one or more sensors. Humidifier controller 128 may be configured to control humidifier 102 using closed-loop control (e.g., using a proportional-integral-derivative (PID) control algorithm).

[0193] In some examples, humidifier 102 may be configured to be controlled by or from gas source 104, or vice versa. Humidifier controller 128 may be configured to control humidifier 102 based at least in part on input received from user interface 114 of gas source 104. Humidifier 102 may be configured to be controlled by gas source controller 112 of gas source 104. Gas source 104 (e.g., gas source controller 112) and humidifier 102 (e.g., humidifier controller 128) may be communicatively coupled via any suitable wired or wireless communication link 134.

[0194] The gas source 104 and the humidifier 102 can be separate devices, such as Figure 1 As shown. In other examples, the gas source 104 and humidifier 102 may, for example, be integrated into a single housing. In such examples, the humidifier supply conduit 116 may be replaced by internal piping. The functions of the gas source controller 112 and the humidifier controller 128 may be performed by a single controller. The user interface 114 and the user interface 132 may be replaced by a single user interface.

[0195] The respiratory support system 100 may include an inspiratory tube 130.

[0196] The inspiratory conduit 130 may be configured to receive a flow of respiratory gas from a humidifier 102 (e.g., chamber outlet 124); or, in an example where the humidifier is omitted, to receive a flow of respiratory gas directly from a gas source 104. The inspiratory conduit 130 may be configured to deliver a flow of respiratory gas to downstream components of the respiratory support system 100 (e.g., a Y-shaped element and / or a patient interface).

[0197] In some examples, the length of the inspiratory conduit 130 may be from about 1.0 meter (m) to about 2.5 m. In some examples, the length of the inspiratory conduit 130 may be from about 1.5 m to 1.8 m, for example, about 1.6 m or 1.8 m. In other examples, for example, for anesthetic applications, the length of the inspiratory conduit 130 may be from about 2.2 m to 2.6 m, for example, about 2.4 m.

[0198] The inspiratory conduit 130 may include an elongated tube. The elongated tube may be flexible. A pair of connectors may be provided at respective ends of the elongated tube for connecting the inspiratory conduit 130 to other components of the respiratory support system 100.

[0199] The elongated tube may be corrugated. In some examples, for example, for adult patients, the maximum outer diameter of the corrugated inspiratory conduit 130 (i.e., the diameter of the inspiratory conduit 130 measured at the outer crest of the corrugation to the outer surface) may be about 20 mm to 30 mm, or about 23 mm to 25 mm, for example, about 24 mm. In other examples, for example, for neonates or pediatric patients, the maximum outer diameter may be about 10 mm to 20 mm, or about 14 mm to 16 mm, for example, about 15 mm. The inspiratory conduit 130 may have a corrugated inner surface. In other examples, the inspiratory conduit 130 may have a substantially smooth (e.g., non-corrugated) inner surface.

[0200] In other examples, the elongated tube may be helical or have a helical outer profile. The helical elongated tube may be formed from one or more helically wound components (e.g., two components wound in a double-helix configuration). The first wound component may be an elongated hollow body, and the second wound component may be an elongated structural component. Heating and / or sensing wires may be embedded in the elongated structural component. Further design and manufacturing details of such catheters are disclosed in U.S. Patent Publications Nos. 2015 / 0306333, 2017 / 0100556, 2019 / 0076620, and 2022 / 0355059, the entire contents of which are incorporated herein by reference.

[0201] The inhalation conduit 130 may include a heater wire 136 (partially illustrated for clarity). For example, the heater wire 136 may be wound around the outside of the elongated tube, embedded within the elongated tube, or located within the inner lumen of the elongated tube. The heater wire 136 may be powered by the humidifier 102. The heater wire 136 may be controlled by the humidifier controller 128. The heater wire 136 may be operated to mitigate heat loss of the breathing gas as it travels along the length of the inhalation conduit 130. In some examples, the heater wire 136 may maintain or, in some cases, increase the temperature of the breathing gas as it travels along the length of the inhalation conduit 130.

[0202] In some examples, sensor probe 138 may be detachably inserted into a sensor probe port at one or more of the humidifier end or patient end of the inhalation conduit 130. Sensor probe 138 may include one or more of, for example, a temperature sensor, a humidity sensor, or a flow sensor. Sensor lead 140 may connect sensor probe 138 to humidifier 102. The signal from sensor probe 138 may be used as an input to one or more of control pressure generator 106, chamber heater 126, or heater lead 136. In some examples, the sensor may be integrated with inhalation conduit 130 (e.g., embedded in it). Sensor lead 140 may be integrated as a sensor lead with an elongated tube (e.g., embedded in it). Alternatively, the sensor may be integrated into humidifier 102.

[0203] In some examples, the inspiratory tubing 130 does not include a sensor probe port or an integrated sensor (e.g., a temperature sensor) at or near the patient end of the inspiratory tubing 130. In some examples, the inspiratory tubing 130 includes neither a sensor probe port nor an integrated sensor. In some examples, the humidifier 102 and / or the respiratory support system 100 does not include a sensor lead 140.

[0204] The connectors can be configured to establish and maintain pneumatic connections to the chamber outlet 124 or the inlet of the Y-shaped element of the humidification chamber 120, respectively. In some examples, such as for adult patients, the connectors may each be adapters with 22mm conical connectors. The connectors may have a 1:40 taper conforming to the International Organization for Standardization (ISO) 5356-1:2015 (Anesthesia and respiratory equipment—Conical connectors—Part 1: Cones and conical sleeves). In other examples, such as for neonatal or pediatric patients, the connectors may be any of a 15mm male conical connector, a 15mm female conical connector, a 12mm male conical connector, a 12mm female conical connector, or any combination of two such connectors.

[0205] In some examples, the connector at the humidifier end of the intake duct 130 may have a socket for receiving the sensor probe 138. In some examples, the connector at the humidifier end of the intake duct 130 may have a socket for establishing an electrical connection between the humidifier 102 and the heater wire 136. In other examples, the connectors at the humidifier ends of the humidifier 102 and the intake duct 130 may have corresponding integrated electrical contacts, thereby establishing both a pneumatic and an electrical connection when the intake duct 130 is physically connected to the humidifier 102.

[0206] The respiratory support system 100 may have a Y-shaped component 142.

[0207] Y-shaped member 142 may include an inhalation inlet. The inhalation inlet may be configured to be coupled to inhalation conduit 130. Y-shaped member 142 may be configured to receive a flow of breathing gas from inhalation conduit 130 during use.

[0208] Y-shaped member 142 may include a breathing inlet / outlet. The breathing inlet / outlet may be configured to couple to one or more of a patient interface 144 or a patient catheter (not shown) (e.g., a cannula connector, between the breathing inlet / outlet and the patient interface 144). The breathing inlet / outlet may be configured to receive a flow of respiratory gas from an inspiratory inlet. The breathing inlet / outlet may be configured to receive exhaled respiratory gas from a patient.

[0209] Y-shaped member 142 may include an expiratory outlet. The expiratory outlet may be configured to couple with an expiratory conduit. The expiratory outlet may be configured to receive exhaled respiratory gas from a patient's respiratory inlet / outlet. The expiratory outlet may be configured to receive, for example, excess respiratory gas from an inspiratory inlet during the patient's expiratory phase. The expiratory outlet may be configured to supply one or more of the patient's exhaled respiratory gas or excess respiratory gas to the expiratory conduit.

[0210] In some examples, the inspiratory inlet and expiratory outlet may converge toward the respiratory inlet / outlet. In other examples, the inspiratory inlet and expiratory outlet may be at least partially parallel to each other.

[0211] The respiratory support system 100 may include a patient interface 144.

[0212] Patient interface 144 can be any suitable non-invasive or invasive patient interface. In some examples, patient interface 144 can be a sealed patient interface. In other examples (e.g., in a respiratory support system configured to deliver high-flow therapy (HFT)), patient interface 144 can be an unsealed patient interface.

[0213] Examples of non-invasive patient interfaces include: Full-face masks, for example, are configured to seal around the patient's eyes, nose, and mouth; A full-face mask, for example, is configured to seal around the patient's nose and mouth; A nasal mask, for example, is configured to seal around a patient's nose; Compact nasal masks, for example, are configured to seal around the nostrils against the underside of the patient's nose; The nasal pillow interface, for example, is configured to seal with each nostril in the patient's nostrils; A sealing nasal cannula, for example, is configured to seal inside each nostril in the patient's nostrils; An unsealed nasal cannula, for example, is configured to extend into the patient's nostrils without obstructing the nasal passages; Face masks, for example, are configured to seal around a patient's mouth; and Combinations of the above items, such as a compact nasal mask and a face mask combination, or a full-face mask and an unsealed nasal cannula combination.

[0214] Examples of invasive patient interfaces include: Endotracheal tube; and Tracheostomy tube.

[0215] In the illustrated example, patient interface 144 is a nasal mask.

[0216] In some examples, the respiratory assist system 100 may be configured or can be configured to deliver a stream of respiratory gases to a patient’s lungs at one or more of a temperature of about 37 degrees Celsius and a relative humidity of about 100%.

[0217] The respiratory support system 100 may include an expiratory tube 146.

[0218] The expiratory conduit 146 may be configured to receive a flow of respiratory gas (e.g., exhaled respiratory gas from a patient and excess respiratory gas from the Y-shaped element 142). The expiratory conduit 146 may be configured to deliver the respiratory gas flow to downstream components of the respiratory support system 100. In some examples, this may be a gas return inlet 148 of the gas source 104, such as... Figure 1 As shown.

[0219] In other examples, such as in a respiratory support system configured to provide bCPAP therapy, the expiratory tubing 146 may be configured to deliver a flow of respiratory gases to a pressure regulator (e.g., an evaporator). An inlet probe may be configured to be immersed in a water reservoir within the evaporator. The depth of the inlet probe determines the pressure of the respiratory gas flow.

[0220] The length of the expiratory tubing 146 in a balanced state may be between approximately 0.8 m and 2.5 m. In some examples, the length of the expiratory tubing 146 may be between approximately 0.8 m and 1.4 m, or between approximately 1.0 m and 1.4 m, for example, approximately 1.2 m. In some examples, the length of the expiratory tubing 146 may be between approximately 1.2 m and 2.0 m, or between approximately 1.4 m and 1.8 m, for example, approximately 1.6 m. In some examples, for example, for anesthetic applications, the length of the expiratory tubing 146 may be between approximately 2.3 m and 2.5 m, for example, approximately 2.4 m.

[0221] The expiratory tubing 146 may include an elongated tube. The elongated tube may be flexible. A pair of connectors may be provided at respective ends of the elongated tube for connecting the expiratory tubing 146 to other components of the respiratory support system 100.

[0222] The elongated tube may be corrugated. In some examples, for example, for adult patients, the maximum outer diameter of the corrugated expiratory conduit 146 (i.e., the diameter of the inspiratory and expiratory conduit 146 measured at the outer crest of the corrugation to the outer surface) may be about 20 mm to 30 mm, or about 23 mm to 25 mm, for example, about 24 mm. In other examples, for example, for neonates or pediatric patients, the maximum outer diameter may be about 10 mm to 20 mm, or about 14 mm to 16 mm, for example, about 15 mm. The expiratory conduit 146 may have a corrugated inner surface. In other examples, the expiratory conduit 146 may have a substantially smooth (e.g., non-corrugated) inner surface.

[0223] In other examples, the elongated tube may be formed from one or more helically wound components as described above with respect to the inhalation conduit 130.

[0224] The connector can be configured to establish and maintain a pneumatic connection with one or more of the Y-shaped element 142, the gas source 104, or an optional filter (not shown) between the expiratory conduit 146 and the gas source 104. One or more of the connectors in the pair may include a conical connector as described above with respect to the inspiratory conduit 130.

[0225] The respiratory gas flow in the respiratory support system 100 may be heated and / or humidified (e.g., for non-invasive ventilation) by one or more of a humidifier 102, a heater lead 136, or the patient's upper airway, and the respiratory gas delivered by the expiratory tube 146 may have a relatively high temperature and humidity. In some examples, the temperature of the respiratory gas may be at least 5°C, or at least 10°C, higher than the temperature of the ambient air 108. In some examples, the respiratory gas may have a relative humidity of up to 100% (i.e., saturated).

[0226] In some examples, the expiratory tubing 146 does not include a heater (e.g., a heater lead). Omitting the heater lead may have one or more of the following advantages: Simplify manufacturing; Reduce manufacturing and material costs; Usability is improved by avoiding the need to establish an electrical connection between the exhalation cannula 146 and a power source such as the humidifier 102 or the gas source 104; Avoid requiring a heater wire control algorithm; Improve security; Reduce the surface temperature of the expiratory cannula 146; Improve aerodynamic performance; Reduce regulatory burden (e.g., International Electrotechnical Commission (EC) 60601-1 (IEC:2005+A1:2012(E)), Section 11.2); Lower the temperature of the breathing gas received by the gas source 104 (e.g., gas return inlet 148); Improve reliability; Extending the warranty period, for example, where electrical insulation is a limiting factor; To achieve a longer service life, for example, where electrical insulation is a limiting factor; or Reduce the power consumption of the expiratory cannula 146, thereby reducing its carbon footprint.

[0227] In some examples, the humidifier 102 is not configured to supply power to the exhalation conduit 146 (e.g., the heater wire of the exhalation conduit 146). In some examples, the humidifier 102 is not configured to control the power delivered to the exhalation conduit 146 (e.g., the heater wire of the exhalation conduit 146).

[0228] In other examples, the exhalation conduit 146 may include heater wires. The heater wires may be similar to heater wires 136 as described above relative to the inhalation conduit 130. The exhalation conduit 146 may be powered by the humidifier 102. The power delivered to the exhalation conduit 146 may be controlled by the humidifier controller 128.

[0229] In some examples, the exhalation tube 146 does not include or is not provided with a water collector for use. Omitting the water collector provides one or more of the following advantages: Simplify manufacturing; Reduce manufacturing and material costs; Improve availability by avoiding the need to empty the water collector; Reduce the risk of infection; Reduce the weight of the expiratory tube 146; Reduce pipe resistance; or Reduce interruptions to treatment.

[0230] In some examples, one or more of the inspiratory conduit 130 or expiratory conduit 146 may have an identification element. For example, the identification element may be a resistor, capacitor, or integrated circuit (IC). The identification element enables one or more of the humidifier 102 or gas source 104 to identify the conduit. In some examples, one or more of the humidifier 102 or gas source 104 may be configured to automatically adjust one or more therapeutic parameters based on the identification of one or more of the inspiratory conduit 130 or expiratory conduit 146. In some examples, the identification element may enable the identification of the conduit's manufacture, type (e.g., model number), or serial number. In some examples, the identification element may be configured to communicate with the humidifier 102 or gas source 104 via a wired connection. In other examples, the identification element may be configured to communicate wirelessly, for example, using radio frequency identification (RFID).

[0231] The respiratory support system 100 may include a filter. The filter may be disposed between the expiratory conduit 146 and the gas source 104 (e.g., gas return inlet 148). In some examples, the filter may be additionally or alternatively disposed within the gas source 104.

[0232] The respiratory support system 100 may include a catheter holder.

[0233] The catheter holder can be configured to receive and hold one or more of the inspiratory catheter 130 or the expiratory catheter 146. The catheter holder can be configured to be fixed in a position near the patient. Using the catheter holder can reduce resistance acting on one or more of the patient catheter, cannula connector, or patient interface 144.

[0234] The humidifier supply conduit 116, the humidification chamber 120, the inhalation conduit 130, the Y-shaped component 142, and the exhalation conduit 146 together form a breathing circuit, more specifically, a dual-limb breathing circuit 150.

[0235] The inspiratory branch 152 of the breathing circuit 150 extends from the gas source 104 to the Y-shaped member 142. In some examples, the inspiratory branch 152 of the breathing circuit 150 may be formed by a combination of a humidifier supply conduit 116, a humidification chamber 120, and an inspiratory conduit 130.

[0236] The expiratory branch 154 of the breathing circuit 150 extends from the Y-shaped member 142 to the gas return inlet 148 of the gas source 104. In some examples, the expiratory branch 154 may be formed by an expiratory conduit 146. In other examples, the expiratory branch 154 may be formed by a combination of the expiratory conduit 146 and a filter. In some examples, the expiratory conduit 146 may form approximately 80%, 90%, 95%, or 100% of the length of the expiratory branch 154.

[0237] Except when parts of the expiratory tubing 146 are unintentionally or temporarily covered by the patient’s limbs, clothing, or bedding, the entire expiratory branch 154 is typically exposed to ambient air 108 of the surrounding environment (e.g., the ward) during use. The flow path within the gas source 104 is not considered part of the expiratory branch 154.

[0238] One or more components of a breathing circuit may be packaged together and sold as a breathing circuit kit. The breathing circuit kit may also include one or more other components of the breathing assist system 100. In some examples, the breathing circuit kit may include any and more of the following: a humidifier supply tubing 116, a humidification chamber 120, an inspiratory tubing 130, a Y-shaped connector 142, an intubation connector, a patient interface, a tubing holder, an expiratory tubing 146, and a filter. In one example, the breathing circuit kit may include a humidifier supply tubing 116, a humidification chamber 120, an inspiratory tubing 130, a Y-shaped connector 142, and an expiratory tubing 146, and optionally a filter.

[0239] In some examples, the breathing circuit kit may be at least partially pre-assembled. A humidifier supply conduit 116 may connect to a humidification chamber 120 (e.g., chamber inlet 122). An inspiratory conduit 130 may connect to a humidification chamber 120 (e.g., chamber outlet 124). One or more of the inspiratory conduit 130 or expiratory conduit 146 may connect to a Y-shaped member 142. A pre-assembled breathing circuit kit may provide one or more of the following benefits: faster setup of the respiratory support system 100, or reduced risk of misconnection (e.g., interchangeability) of the inspiratory and expiratory conduits 130 and 146.

[0240] In some examples, the components of a breathing circuit kit may be packaged together in a sealed plastic bag, for example. Multiple breathing circuit kits (e.g., 10 breathing circuit kits) may be packaged together in a cardboard box, for example.

[0241] Figure 2 An example humidifier 102 that can be used in the respiratory support system 100 is illustrated in more detail, and the humidifier supply conduit 116 and the inhalation conduit 130 are also shown in part.

[0242] In some examples, humidifier 102 may be an F&P 950™ breathing humidifier purchased from Fisher & Paykel Healthcare Limited in Auckland, New Zealand.

[0243] The humidifier 102 may include a heater base 202 and a humidification chamber 120.

[0244] Humidifier 102 (e.g., heater base 202) may include housing 204. Housing 204 may be configured to at least partially house one or more components of humidifier 102, such as humidifier controller 128, user interface 132, room heater, box 206, one or more sensors or power supplies.

[0245] The heater base 202 may include a chamber heater 126. The heater base 202 may be configured to heat a volume of water contained within the humidification chamber 120 during use. The chamber heater 126 may include a heater plate. The chamber heater 126 may include a heating element. The chamber heater 126 may include a ceramic heater.

[0246] In some examples, the chamber heater 126 may be resiliently mounted to the heater base 202. The chamber heater 126 may be a spring-loaded chamber heater. In use, the spring-loaded chamber heater 126 may apply a force to the humidification chamber 120, for example, an upward force to the bottom of the humidification chamber 120.

[0247] The humidifier 102 (e.g., heater base 202) may include a user interface 132. The user interface 132 may be configured to receive input from a user (e.g., a healthcare professional and / or a patient). The user interface 132 may be configured to display information to the user.

[0248] User interface 132 may include one or more buttons 208. The one or more buttons 208 may be push-buttons or touch-sensitive buttons. In some examples, user interface 132 may include a power button configured to be operated by a user, for example, to turn the humidifier 102 on or off, or to put the humidifier 102 into standby mode. In some examples, one or more buttons among the buttons 208 may be supplemented or replaced by one or more switches, dials, or sliders.

[0249] User interface 132 may include display 210. Display 210 may be a liquid crystal display (LCD) or an organic light-emitting diode (OLED) display. Display 210 may be configured to display information to a user. In some examples, display 210 may be a touch-sensitive display. Touch-sensitive display may be configured to receive input from a user.

[0250] User interface 132 may include one or more indicator lights 212. The one or more indicator lights 212 may be configured to visually convey information to the user and / or visually attract attention to the humidifier 102. For example, indicator lights 212 may be light-emitting diodes (LEDs). In some examples, indicator lights 212 may be illuminated during use to signal an alarm condition. In some examples, indicator lights 212 may be multi-colored, for example, selectively illuminated in two or more different colors, such as green, amber, or red. In some examples, indicator lights 212 may illuminate intermittently, for example, flashing intermittently in a certain pattern. For example, the severity of the alarm condition may be indicated by one or more of the color, intermittent illumination, intermittent illumination pattern, or brightness of one or more indicator lights 212. Further information about the alarm condition may be displayed or can be displayed on display 210.

[0251] User interface 132 may include an audio device. The audio device may be configured to convey information to the user audio and / or attract attention to the humidifier 102 audio. For example, the audio device may be a buzzer or a speaker. In some examples, the audio device may emit an audible alarm to signal an alarm condition. In some examples, the audio device may be operable to generate two or more distinct tones or sounds. In some examples, the audible alarm may sound intermittently. For example, the severity of the alarm may be indicated by one or more of the tone or sound, frequency, or volume of the audible alarm. Further information about the alarm condition may be displayed or can be displayed on display 210.

[0252] The humidifier 102 (e.g., heater base 202) may include a housing 206. The housing 206 may be removably attached to the housing 204 of the heater base 202.

[0253] Container 206 may be a sub-housing. Container 206 may include electronic equipment. The electronic equipment may include one or more sensors. The sensors of container 206 may be configured to sense one or more properties of the breathing gas flow through humidification chamber 120 during use, such as one or more of the temperature, humidity, or flow rate of the breathing gas flow. The sensors may be disposed on one or more sensor probes protruding from container 206. During use, the sensor probes may protrude through an orifice in humidification chamber 120 (e.g., in one or more of the chamber inlet or chamber outlet). The orifice may be sealed or closed by an elastomeric seal. The elastomeric seal may elastically deform through the sensor probes when humidification chamber 120 is received by heater base 202.

[0254] The electronics of box 206 may include an electrical connector configured to be electrically connected to heater base 202 for communication (e.g., serial communication) with or within a humidifier controller.

[0255] The electronic equipment of box 206 may include an electrical connector configured to be electrically connected to the inhalation duct 130.

[0256] The electronic device of box 206 may include one or more processors configured to communicate with one or more of the sensors and humidifier controllers.

[0257] The heater base 202 can be fitted with a replacement box 206. The replacement box 206 can be configured to provide new or improved functionality to the humidifier 102.

[0258] Humidifier 102 (e.g., heater base 202 and / or box 206) may include as referenced above. Figure 1 The humidifier controller 128 is described.

[0259] In some examples, humidifier 102 (e.g., housing 206) may have a socket or integrated cable configured to optionally connect to exhalation conduit 146. Humidifier 102 may be configured to supply power to exhalation conduit 146. Humidifier controller 128 may be configured to control the power supplied to optional heater wires of exhalation conduit 146.

[0260] The humidification chamber 120 can be configured to be detachably received by the heater base 202 and secured to thermally contact the chamber heater 126.

[0261] The humidification chamber 120 may include a hollow body and a heat conductor, which together are configured to define a chamber containing a volume of water. The humidification chamber 120 may include a sealing element configured to form a seal between the hollow body and the heat conductor.

[0262] The hollow body can be dome-shaped and has an opening that is configured to be closed by a heat conductor.

[0263] The hollow body may include a chamber inlet 122 and a chamber outlet 124, for example, extending through the upper surface of the hollow body. In some examples, the chamber inlet 122 may be arranged vertically. The humidification chamber 120 (e.g., chamber inlet 122) may include a baffle to redirect the inflowing breathing gas flow. The baffle may prevent the inflowing breathing gas flow from being directly directed to the water surface, which would otherwise cause ripples or splashes. The baffle may increase the residence time within the humidification chamber 120, for example, by preventing the breathing gas flow from flowing directly from the chamber inlet 122 to the chamber outlet 124. In some examples, the chamber outlet 124 may be arranged horizontally. The chamber outlet may include a bend, for example, to redirect the breathing gas flow from a vertical direction to a horizontal direction during use.

[0264] Hollow bodies can be transparent. Hollow bodies can be formed from relatively rigid plastic materials such as polycarbonate or acrylonitrile butadiene styrene (ABS).

[0265] When the humidification chamber 120 is received by the heater base 202, the heat conductor can be configured to engage with and conduct heat from the chamber heater 126 of the heater base 202. For example, the heat conductor can be formed of aluminum or stainless steel. In some examples, the heat conductor can be permanently coupled to the hollow body, for example, by press-fitting. The humidification chamber 120 can be disposable. In other examples, the hollow body can be detachably coupled to the heat conductor, for example, by friction fit. The humidification chamber 120 can be autoclaved. The humidification chamber 120 can be reusable.

[0266] In some examples, the humidification chamber 120 may be configured to replenish water during use (e.g., via a gravity feed device or pump). The humidification chamber 120 may include a water tube and a needle. The needle may be configured to pierce a water source (e.g., a sterile water bag) to couple the water source to the internal fluid of the humidification chamber 120 via the water tube. The humidification chamber 120 may include a float valve. The float valve may be configured to automatically control the water flow to maintain the volume of water within the humidification chamber 120 above and / or within a predetermined range.

[0267] The humidifier supply conduit 116 may include a connector 214. The connector 214 may be configured to establish a pneumatic connection with the humidification chamber 120 (e.g., chamber inlet 122). The connector 214 may include a bend with an angle, for example, between about 90° and 175°, or between about 100° and 145°, or about 120°.

[0268] The intake duct 130 may include a connector 216 (e.g., an electro-pneumatic connector). The connector 216 may be configured to establish a pneumatic connection with the humidification chamber 120 (e.g., chamber outlet 124). The connector 216 may also be configured to establish an electrical connection with the heater base 202 (e.g., housing 206).

[0269] Connector 216 may form a releasable and lockable connection with one or more of the humidification chamber 120 or the heater base 202 (e.g., housing 206). Connector 216 may be configured to provide one or more of tactile or auditory feedback when the releasable and lockable connection is established. Connector 216 may include a release button 218. Release button 218 may be actuated to facilitate disconnection of the inhalation duct 130 from the humidifier 102.

[0270] In some examples, connector 216 may be configured to be physically and pneumatically coupled to humidification chamber 120 (e.g., chamber outlet) before humidification chamber 120 is mounted on heater base 202, and to be electrically connected to heater base 202 (e.g., housing 206) when humidification chamber 120 is mounted on heater base 202 in a sliding motion (e.g., horizontally).

[0271] In some examples, connector 216 may be configured such that it can be pneumatically coupled to humidifier 120 when humidifier 120 has been mounted on heater base 202, and substantially simultaneously electrically connected to heater base 202 (e.g., housing 206) (e.g., with only one action). This allows humidifier 120 and inhalation duct 130 to be supplied, pre-assembled, and ready to be used, for example, as part of a breathing circuit kit.

[0272] Connector 216 may include electrical terminals coupled to a pair of sensor wires of the inhalation duct 130. The sensor wires may be embedded within the wall of the inhalation duct 130. The sensor wires may be configured to form a sensing loop with the sensor, for example, at the distal end of the inhalation duct 130 and at the heater base 202 (e.g., housing 206).

[0273] Connector 216 may include electrical terminals coupled to a pair of heater wires 136 of the intake conduit 130. The heater wires 136 may be electrically coupled, for example, at a distal end of the intake conduit 130. The heater wires 136 may be configured to form a heating circuit with the heater base 202 (e.g., housing 206).

[0274] Connector 216 may include electrical terminals electrically coupled to an identification element (e.g., a resistor). The identification element may be embedded within connector 216. Humidifier 102 (e.g., humidifier controller 128 or housing 206) may be configured to identify, for example, the type of inhalation duct 130 coupled to humidifier 102 during use by determining the resistance of a resistor. For example, a resistance of about 100 ohms (Ω) may indicate that a first type of inhalation duct 130 (e.g., an adult duct) is connected to humidifier 102. For example, a resistance of about 200 Ω may indicate that a second type of inhalation duct 130 (e.g., a neonatal duct) is connected to humidifier 102. The humidifier controller may be configured to adjust control accordingly. For example, an adult duct may include a single heating zone, while a neonatal duct may include two or more heating zones. In some examples, two heating zones may be selectively operated based on the polarity of the potential difference applied to a pair of electrical terminals.

[0275] The electrical terminals of connector 216 can be configured to make electrical connections with corresponding terminals of humidifier 102 (e.g., housing 206).

[0276] Various example medical gas catheters and variations are described in detail below with particular reference to the expiratory catheter 146 used as a respiratory support system 100. However, the example expiratory catheter 146 may alternatively be used or modified for use in alternative medical gas systems.

[0277] Except for the differences described below or otherwise apparent in the accompanying drawings, the following example expiratory tubing and variations may resemble the expiratory tubing 146 of the example respiratory assist system.

[0278] breathable materials

[0279] In some examples, medical gas conduits may be formed at least partially of a breathable material (as defined in the glossary below). Breathable materials and medical gas conduits including such materials are disclosed in International Patent Application No. PCT / NZ2023 / 050040, entitled “Medical Gases Conduit,” published under International Publication No. WO 2023 / 195865 A1, the entire contents of which are incorporated herein by reference.

[0280] Breathable materials can allow water molecules to permeate, but are relatively impermeable to liquid water and breathable gases. Under a scanning electron microscope (SEM) at magnification of 150x or 2500x, breathable materials (e.g., unfoamed breathable materials) may have no channels or pores. Foamed breathable materials may have many closed pores, but lack open channels or pores extending from one main surface of the breathable material to another. Water molecules can be absorbed by the breathable material, diffuse through the breathable material, and desorb into the ambient air. This is known as the dissolution-diffusion mechanism. Water molecules can pass through the breathable material according to a gradient from the higher humidity side (e.g., within the lumen of a medical gas conduit) to the lower humidity side (e.g., exposed to ambient air).

[0281] In contrast, porous materials (e.g., porous membranes, such as expanded polytetrafluoroethylene (ePTFE) fabrics (e.g., Gore-Tex purchased from WL Gore & Associates) ® Fabrics have open channels extending from one main surface to another. Porous materials allow water molecules to permeate through pore flow mechanisms. Water flows from one side of the porous material to the other via the open channels. These open channels may also allow pathogens to pass through.

[0282] In some examples, the breathable material may be a block polymer. The block polymer may include polybutylene terephthalate hard segments. The block polymer may include polyether-type macromolecular glycol soft segments. In some examples, one or more additives may be added to the breathable material. For example, additives may include one or more of a foaming agent, a colorant, a UV stabilizer, a UV absorber, or a processing aid. In some examples, the additive may constitute up to about 10%, up to about 8%, up to about 5%, or up to about 3% (e.g., about 3% or 1.5%) of the breathable material of the slender tube by mass, weight, or volume.

[0283] Using breathable materials in an expiratory duct can reduce the absolute and relative humidity of the respiratory gas flow within the duct as it travels along its length. This, in turn, lowers the dew point of the respiratory gas flow.

[0284] Examples of medical gas catheters that include breathable materials include various breathing circuits using EVAQUA™ technology purchased from Fisher & Paykel Healthcare (such as the RT280 with EVAQUA™ technology). ™Expiratory tubing (including the RT340™ adult breathing circuit). These expiratory tubings include a heater lead but not a water collector. These expiratory tubings have been shown to effectively reduce condensation formation within the tubing. However, it has been found that under at least some conditions, condensation or other liquids (e.g., from other sources such as the intubation connector, the patient, or the nebulizer) can still accumulate in the expiratory tubing during prolonged use. Details of such expiratory tubings are disclosed in U.S. Patent Nos. 6,769,431 and 10,532,177, both of which have been assigned to Fisher & Paykel Healthcare Limited.

[0285] It has been found that breathable materials with higher permeability to water molecules may more effectively reduce the buildup of condensation or other liquids within the exhalation cannula. Therefore, exhalation cannulas formed from relatively more breathable materials may require less or less frequent intervention to remove condensation. Furthermore, in at least some examples, breathable materials with higher permeability to water molecules allow for the omission of heater wires from the exhalation cannula.

[0286] However, it has been found that such breathable materials absorb a relatively large number of water molecules during use, thus significantly altering the mechanical properties of the expiratory tubing. For example, the breathable material may expand, become less rigid, and / or become less elastic. This can present challenges in meeting certain standards or other design requirements, for example, under a range of different conditions. For instance, tubing in a respiratory support system may need to meet certain minimum requirements specified in formal standards, such as ISO 5367:2014(E) (Anesthesia and Respiratory Equipment — Respiratory Kits and Connectors). This standard specifies the basic requirements for the following aspects: i. Materials; ii. Length; iii. Connection; iv. Leakage; v. Flow resistance; and vi. To be compliant.

[0287] Due to these changes in mechanical properties, an expiratory cannula that meets certain standards or other design requirements before use may not necessarily meet those standards or other design requirements during or immediately after use in a respiratory support system.

[0288] Because the condition of a medical gas catheter may vary during use, throughout the detailed description and claims, the terms “dry state,” “equilibrium state,” “regulated state,” and “saturated state” refer to various different states or ranges of states of the expiratory catheter or tube. These states are each defined in the glossary below.

[0289] Figure 3 An exhalation tube 146 according to a first example is illustrated in an illustrative form (e.g., not to scale). The exhalation tube 146 is shown in a balanced state (e.g., before use).

[0290] The exhalation cannula 146 may include a pair of connectors 302, 304. The first connector 302 may be configured to connect to the Y-shaped member 142 (e.g., the exhalation outlet of the Y-shaped member 142). The second connector 304 may be configured to connect to one or more of a filter or gas source 104 (e.g., a gas return inlet 148). In some examples, connectors 302, 304 may be identical. In other examples, connectors 302, 304 may differ in one or more aspects such as size, material, or markings.

[0291] The expiratory tubing 146 may include an elongated tube 306. The elongated tube 306 may define an inner lumen through which breathing gas flows (e.g., between connectors 302, 304).

[0292] The elongated tube 306 may be at least partially formed of a breathable material. The breathable material may extend to cover the entire length of the elongated tube 306 and may extend to cover most of the expiratory branch 154 of the respiratory assist system 100, for example, excluding only connectors 302, 304 and the filter optionally between the expiratory conduit 146 and the gas source 104 (e.g., gas return inlet 148).

[0293] In the immersion test (described in the glossary below), the sample specimen of the elongated tube 306 can absorb more than about 33%, about 33% to 200%, about 100% to 160%, about 120% to 140%, or about 130% to 135% (e.g., about 133%) of its own mass of water molecules.

[0294] In some examples, the sample specimen of the elongated tube 306 expands by about 20% to 70% in one or more of the radial direction (e.g., maximum outer diameter), the longitudinal direction (i.e., length), or the wall thickness of the elongated tube. In some examples, the sample specimen of the elongated tube 306 may expand by about 20% to 70%, about 25% to 50%, or about 30% to 50% in one or more of the radial direction, the longitudinal direction, or the wall thickness. In one example, the sample specimen of the elongated tube 306 was found to expand by about 42% in the radial direction, about 37% in the longitudinal direction, and about 34% in the wall thickness. In another example, the sample specimen of the elongated tube 306 was found to expand by about 32% in each of the radial direction, the longitudinal direction, and the wall thickness.

[0295] In some examples, the wall thickness of the elongated tube 306 in the dry state may be between about 0.5 mm and 0.9 mm, between about 0.6 mm and 0.8 mm, between about 0.65 mm and 0.75 mm, between about 0.68 mm and 0.72 mm, or between about 0.69 mm and 0.71 mm, for example, about 0.70 mm. In the saturated state, the wall thickness of the same elongated tube 306 may be between about 0.7 mm and 1.1 mm, between about 0.8 mm and 1.0 mm, between about 0.85 mm and 0.95 mm, between about 0.90 mm and 0.94 mm, or between about 0.91 mm and 0.93 mm, for example, about 0.92 mm.

[0296] In some examples, the maximum outer diameter of the elongated tube in the dry state may be between about 20 mm and 26 mm, between about 21 mm and 25 mm, or between about 22 mm and 24 mm, for example, about 23 mm. In the saturated state, the maximum outer diameter of the same elongated tube 306 may be between about 25 mm and 35 mm, between about 28 mm and 32 mm, or between about 29 mm and 31 mm, for example, about 30 mm.

[0297] In some examples, the exhalation cannula 146 may include one or more intermediate connectors, such as a midpoint connector located at or near the midpoint between connectors 302 and 304. In some examples, the exhalation cannula 146 may include two or more elongated tubes 306. The two or more elongated tubes 306 may be identical or different. At least one of the two or more elongated tubes 306 may be at least partially formed of a breathable material. An intermediate connector may connect (e.g., permanently connect) two elongated tubes together.

[0298] Figure 3 The exhalation cannula 146 is shown in a balanced state (e.g., before use). In the balanced state, the diameter of the elongated tube 306 may be substantially uniform along the length of the elongated tube 306 (e.g., between connectors 302, 304).

[0299] In use, gas source 104 provides a flow of breathing gases. This flow of breathing gases may be heated and / or humidified by one or more of the humidifier 102, the heater wire 136 in the inspiratory conduit 130, and / or the patient's upper airway before being delivered to gas source 104 via expiratory conduit 146. Some water molecules within expiratory conduit 146 will be absorbed by the breathable material of elongated tube 306. For example, water molecules may be absorbed from one or more of the following: a flow of breathing gases (e.g., in the form of water vapor), condensate (e.g., in the form of liquid water) (which may form within the lumen), or condensate or other liquids (which may have been drained into expiratory conduit 146 from other components of the respiratory support system 100). Water molecules may pass through the breathable material and evaporate into ambient air via a dissolution-diffusion mechanism driven by the difference in water molecule concentration between the inside and outside of the elongated tube.

[0300] When a breathable material absorbs water molecules, it may begin to expand in one or more of the longitudinal, radial, or wall thickness directions. This is known as the conditioning state. After a period of use under essentially constant conditions, the breathable material reaches a stable state, for example, it stops expanding.

[0301] Figure 4 Examples of those in a state of adjustment are shown. Figure 3 The exhalation cannula 146, for example, as may occur after a period of use. Water molecules evaporate from the breathable material into the ambient air 108, indicated by arrows.

[0302] Although shown as arranged in a linear configuration for illustrative purposes, it should be understood that the expiratory conduit 146 may be flexible and may hang between the Y-shaped member 142 and the gas source 104 in use. References to terms such as “longitudinal” and “axis” throughout the specification and claims are not intended to imply that the expiratory conduit 146 must be arranged in a linear manner.

[0303] also, Figure 4 This is an illustrative representation and is not shown to scale. Exaggerations may be made for illustrative purposes. It should also be understood that... Figure 4 One of the many possible adjustment states is illustrated. The size and mechanical properties of the expiratory tubing 146 may depend, for example, on the nebulizing substance or multiple variables, including but not limited to: such as usage time, temperature of the breathing gas, humidity of the breathing gas, temperature of the ambient air, humidity of the ambient air, movement of the ambient air, routing of the expiratory tubing, type and model of the gas source, type and model of the humidifier, patient condition, and humidity contribution.

[0304] As illustrated, the slender tube 306 can expand in both the longitudinal and radial directions. Although it is impossible to... Figure 4It is evident that the slender tube 306 can also expand along the wall thickness.

[0305] like Figure 4 As illustrated, the radial expansion of the expiratory conduit 146 along its length (e.g., between connectors 302, 304) is not necessarily uniform. Although it is impossible to determine from... Figure 4 It is evident that, however, the expansion along the longitudinal direction and / or the wall thickness along the length of the expiratory conduit 146 (e.g., between connectors 302, 304) is not necessarily uniform.

[0306] The elongated tube 306 may tend to expand more in one or more regions than in one or more other regions. In some examples, local expansion of the elongated tube 306 may occur in any or more of the inlet region 402, the outlet region 404, or the intermediate region 406.

[0307] The inlet region 402 may be within or corresponding to a portion of the length of the elongated tube 306, which is closest to one or more of the Y-shaped member 142, the patient interface 144, or the patient. In some examples, the inlet region 402 may be up to about 50%, up to about 33%, up to about 25%, up to about 20%, or up to about 10% of the length of the elongated tube 306 between the connectors 302 and 304.

[0308] It has been found that at least one of the relative or absolute humidity of the breathing gas, or the volume of condensate or other liquid within the lumen of the elongated tube 306, may increase in the inlet region 402 relative to one or more other regions of the elongated tube 306. For example, the increase in humidity relative to another region may be due to the dehumidifying effect of the breathable material as the breathing gas passes along the length of the lumen. For example, the increase in the volume of condensate or other liquid in the inlet region 402 may be due to condensate or other liquid draining into the inlet region 402 from upstream of the expiratory conduit 146 (e.g., the Y-shaped member 142, the cannula connector, the patient interface 144, or one or more of the patient). If the elongated tube 306 is corrugated, condensate or other liquid may accumulate within the corrugations in the inlet region 402.

[0309] The outlet region 404 may be within or corresponding to a portion of the length of the elongated tube 306, which is closest to one or more of the filter, gas source 104, or gas return inlet 148. In some examples, the outlet region 404 may be up to about 50%, up to about 33%, up to about 25%, up to about 20%, or up to about 10% of the length of the elongated tube 306.

[0310] It has been found that at least one of the relative or absolute humidity of the breathing gas, or the volume of condensate or other liquid within the cavity of the elongated tube 306, may increase in the outlet region 404 relative to one or more other regions of the elongated tube 306. For example, the increase in humidity or volume of condensate or other liquid may be due to condensate being discharged from the filter or gas source 104 into the outlet region 30.

[0311] Intermediate region 406 may be within or corresponding to a portion of the length of elongated tube 306, which is located downstream of inlet region 402 and upstream of outlet region 404. Intermediate region 406 may be up to about 50%, up to about 33%, up to about 25%, up to about 20%, or up to about 10% of the length of elongated tube 306.

[0312] It has been found that at least one of the relative or absolute humidity of the exhaled gas and the volume of condensate or other liquid within the lumen of the elongated tube 306 may increase in the intermediate region 406 relative to one or more other regions of the elongated tube 306, for example, relative to the region between the inlet region 402 and the intermediate region 406, or relative to the region between the intermediate region 406 and the outlet region 404. The flexibility of the expiratory conduit 146 means that the expiratory conduit 146 may tend to droop between the Y-shaped member 142 and the gas source 104. This droop may result in the intermediate region 406 being the lowest point of the expiratory conduit 146, and due to gravity, any condensate or other liquid within the lumen may tend to drain towards the intermediate region 406 and accumulate in that intermediate region.

[0313] exist Figure 4 In the diagram, local expansion in the radial direction is illustrated in inlet region 402 and outlet region 404. Local expansion may manifest as a protrusion 408 in a portion of the elongated tube 306. The protrusion 408 may taper gradually from its widest point toward adjacent regions of the elongated tube 306. If local expansion occurs in two or more regions, one region (e.g., inlet region 402) may expand more than another region (e.g., outlet region 404). In some examples, it has been found that, in use, local expansion may occur first in one region (e.g., inlet region 402) and then in another region (e.g., outlet region 404 or intermediate region 406).

[0314] It should be understood that the term "localized expansion" is not intended to mean that expansion is limited to one or more regions. The term is used in a relative sense. That is, in the region where localized expansion occurs, the degree of expansion may be more pronounced than in adjacent regions.

[0315] It has been found that the expansion of breathable materials may increase their permeability to water molecules (e.g., compared to more restricted breathable materials under the same conditions). This may be at least partly attributed to the relatively large surface area of ​​the expanded breathable material.

[0316] The non-uniform expansion of the elongated tube 306 can advantageously improve the permeability of the elongated tube to water molecules at the most needed locations (e.g., one or more of the inlet region 402, outlet region 404, and intermediate region 406). In use, the elongated tube 306 can automatically adapt to different or constantly changing operating conditions. In contrast, a collector is provided at a fixed location along the length of the conduit. The fixed location may not necessarily coincide with the lowest point of the conduit. Furthermore, the corrugations in the elongated tube 306 may inhibit the discharge of condensate or other liquids from one or more of the inlet region 402 or outlet region 404 into the collector, at least until sufficient condensate or liquid has accumulated to overflow from one corrugation to the next.

[0317] exist Figure 4 In the illustrated examples, the expansion of the elongated tube 306 may be suppressed only by the connectors 302, 304. However, in other examples, as described below, the expansion of at least a portion of the elongated tube 306 along any one or more of the longitudinal direction, radial direction, or wall thickness may be suppressed. In some examples, the expiratory conduit 146 may be configured to expand more in the radial direction than in the longitudinal direction (e.g., proportionally). In some examples, the expiratory conduit 146 may be configured to expand primarily or only in the longitudinal direction. In other examples, the expiratory conduit 146 may be configured to expand primarily or only in one or more of the radial direction or wall thickness.

[0318] Reinforcing components

[0319] Figure 5 An example of an expiratory tube 146 is shown in schematic form.

[0320] The expiratory tubing 146 may include one or more reinforcing members 502. The reinforcing members 502 may reduce the risk of partial or complete blockage of the elongated tubing 306 when subjected to external mechanical forces.

[0321] The reinforcing member 502 may be an internal reinforcing member (e.g., at least partially disposed within the inner cavity of the elongated tube 306). In other examples, as described below, the reinforcing member may be an external reinforcing member (e.g., at least partially disposed around the outer periphery of the elongated tube 306).

[0322] The reinforcing member 502 may be securely attached to one or more of connectors 302, 304, or elongated tube 306. In some examples, the respective ends of the reinforcing member 502 may be securely attached to connectors 302 and 304. In other examples, the reinforcing member 502 may be attached to the exhalation cannula 146, for example, by one or more clips. The clips may engage with the corrugations (e.g., inner troughs) of the elongated tube 306.

[0323] The reinforcing member 502 may have a helical shape. The reinforcing member 502 may be at least partially formed of an elastic material. The elastic material may be semi-rigid. The reinforcing member 502 may be configured to elastically return to its original shape after being compressed or stretched. Figure 5 An example is shown of a reinforcing member 502 in an extended state, which applies a force in the direction indicated by arrow 504. This force can at least partially inhibit the longitudinal expansion of the elongated tube 306 when it absorbs water molecules during use.

[0324] In some examples, the reinforcing member 502 may prevent the exhalation conduit 146 (e.g., the elongated tube 306) from expanding in the longitudinal direction. The reinforcing member 502 may bias the exhalation conduit 146 (e.g., the elongated tube 306) toward a predetermined length. When the elongated tube 306 is in equilibrium without the reinforcing member 502, the predetermined length may be approximately equal to the length of the exhalation conduit 146. The exhalation conduit 146 may be configured such that the reinforcing member 502 is substantially unloaded when the exhalation conduit 146 is in equilibrium. The reinforcing member 502 may be configured to be in a taut state when the elongated tube 306 is in an adjusted state (e.g., when the elongated tube 306 expands in the longitudinal direction during use due to the absorption of water molecules).

[0325] In some examples, under one or more of a balanced or regulated state, the reinforcing member 502 can improve the crush resistance of at least a portion of the expiratory conduit 146 (e.g., at least a portion of the elongated tube 306). Crushing resistance can refer to the ability of the expiratory conduit 146 to resist an applied force that reduces the cross-sectional area of ​​the lumen. Crushing resistance can be tested by applying, for example, a force of about 20 N and measuring the final radial deformation of the expiratory conduit 146. In another example, crush resistance can be tested by measuring the force required to achieve a radial deformation of about 10 mm. The improvement in crush resistance due to the reinforcing member 502 can be evaluated by comparing the crush resistance of conduits with and without the reinforcing member 502.

[0326] The reinforcing member 502 may be configured to be more rigid than the elongated tube 306 (e.g., when the elongated tube 306 is in one or more of an adjusted or saturated state). For example, improving the crush resistance in the inlet region 402 may reduce the risk of the elongated tube being crushed or blocked by the patient's body (e.g., limbs), or may reduce the risk of the elongated tube being crushed or blocked between the patient's bed and other furniture.

[0327] In some examples, the reinforcing member 502 can improve the crush resilience of at least a portion of the expiratory conduit 146 (e.g., at least a portion of the elongated tube 306). Crushing resilience can refer to the ability of the expiratory conduit 146 to return to or tend towards an undeformed state after the crushing force is removed. Crushing resilience can be measured by measuring the flow resistance of the expiratory conduit 146 after a load that substantially or completely blocks the expiratory conduit 146 has been applied and removed. Acceptable crush resilience can be less than about 150% of the flow resistance before crushing. The improvement in crush resilience due to the reinforcing member 502 can be evaluated by comparing the crush resilience of conduits with and without the reinforcing member 502.

[0328] In some examples, the reinforcing member 502 may not be attached to the elongated tube 306 at all. In some examples, the reinforcing member 502 may be fixedly attached only to the connectors 302, 304. In other examples, the reinforcing member 502 may be fixedly attached to the elongated tube 306 only at or near its respective end (e.g., within the connectors 302, 304). The reinforcing member 502 may prevent the expiratory tube 146 from expanding in the longitudinal direction and / or improve one or more of the crush resistance or crush recovery of the elongated tube 306. The reinforcing member 502 may allow local expansion, for example, in the longitudinal direction, in one or more regions of the elongated tube 306 (e.g., inlet region 402). In some examples, local expansion may be compensated at least partially by local compression of another portion of the elongated tube 306 (e.g., between inlet region 402 and intermediate region 406).

[0329] In some examples, the reinforcing member 502 may be securely attached to the elongated tube 306 at multiple discrete locations along the length of the elongated tube 306 (e.g., multiple discrete locations between connectors 302, 304). In some examples, such as Figure 5 As shown, the slender tube 306 may be corrugated. The reinforcing member 502 may be present at each corrugation or at each... n One ripple (among which) nThe reinforcing member 502 (a natural number) is fixedly attached to the elongated tube 306. This attachment between the reinforcing member 502 and the elongated tube 306 prevents at least a portion of the elongated tube 306 from expanding radially and / or inhibits at least a portion of the exhalation conduit 146 from partially expanding longitudinally. In some examples, the reinforcing member 502 may be configured to allow at least partial expansion longitudinally between successive attachments. Allowing partial expansion improves the permeability of that portion of the elongated tube 306 to water molecules.

[0330] In some examples, the pitch of the helical reinforcement member 502 may vary along its length. The pitch can be measured as the distance between the respective centers of adjacent coils of the reinforcement member 502. In some examples, the pitch may be changed such that the reinforcement member 502 prevents two or more regions of the elongated tube 306 from expanding to different degrees. For example, a reinforcement member 502 with a relatively low pitch in the inlet region 402 may allow the elongated tube 306 to expand more longitudinally than in another region (e.g., outlet region 404) where the reinforcement member 502 has a relatively high pitch. In some examples, the pitch may be changed such that the reinforcement member 502 provides different levels of crush resistance or crush recovery for different regions of the elongated tube 306. For example, a reinforcement member 502 with a relatively low pitch in the inlet region 402 may provide improved crush resistance of the expiratory conduit 146 in that region compared to another region (e.g., outlet region 404) where the reinforcement member 502 has a relatively high pitch.

[0331] Figure 6 This is a detailed perspective view of a portion of another example expiratory catheter, including reinforcing member 502.

[0332] The elongated tube 306 in this example may be uncorrugated (e.g., substantially smooth). In some examples, the reinforcing member 502 may improve one or more of crush resistance or crush recovery to the extent that corrugation is not required. An uncorrugated elongated tube may have lower flow resistance compared to a corrugated elongated tube with the same maximum inner diameter (i.e., measured between the inner troughs of the corrugations). Alternatively, the inner diameter of the uncorrugated elongated tube 306 may be smaller than the maximum inner diameter of a corrugated tube with equivalent flow resistance. The uncorrugated elongated tube may allow condensate or other liquids to drain more smoothly, for example, from one or more of the patient, Y-shaped member 142, filter, or gas source 104, to the central region 406 of the elongated tube 306.

[0333] although Figure 6 Not shown in the image, but Figure 6 The exhalation tubing may also include connectors 302, 304 located at the respective ends of the elongated tube 306.

[0334] In some examples, as illustrated, the reinforcing member 502 may have a circular cross-section. In other examples, the reinforcing member 502 may have an elliptical cross-section or a polygonal cross-section (e.g., square or rectangular).

[0335] In some examples, the reinforcing member 502 may be continuously engaged with the elongated tube 306 along at least a portion of its longitudinal length (e.g., at least 25%, at least 50%, at least 75%, at least 90%, or about 100% of the total length of the reinforcing member 502) or along the length of the reinforcing member 502 between connectors 302, 304. In some examples, as described, the reinforcing member 502 may be continuously engaged with at least a portion of the elongated tube 306 when the elongated tube 306 is in one state (e.g., one or more of a dry state or an equilibrium state), but not engaged with the elongated tube 306 when the elongated tube 306 is in another state (e.g., one or more of a conditioned state or a saturated state). In use, as the elongated tube 306 absorbs water molecules, it may expand in both the longitudinal and radial directions. The expansion of the elongated tube 306 in the longitudinal and radial directions may be positively correlated. However, the length and diameter of the reinforcing member 502 may be negatively correlated. As the reinforcing member 502 extends longitudinally due to the expansion of the elongated tube 306, its diameter can be reduced. In use, the reinforcing member 502, which is fixedly attached to the connectors 302, 304 at opposite ends, can be spaced apart (or further spaced apart) from the inner surface of the elongated tube 306.

[0336] In other examples, the reinforcing member 502 may be fixedly attached to the elongated tube 306, for example, by adhesive or welding. The reinforcing member 502 may be continuously and fixedly attached to the elongated tube 306 along at least a portion of its longitudinal length (e.g., at least 25%, at least 50%, at least 75%, at least 90%, or about 100% of the total length of the reinforcing member 502) or along the length of the reinforcing member 502 between connectors 302, 304. Continuous attachment better suppresses radial expansion of the elongated tube 306. Partial radial expansion is still permitted between adjacent coils of the reinforcing member 502.

[0337] In other examples, the reinforcing member 502 may be embedded in the elongated tube 306.

[0338] Figure 7 This is a schematic diagram of another example of an exhalation tube 146, which includes reinforcing components, in an illustrative form.

[0339] The reinforcing member 502 may have a non-helical shape (e.g., a linear or curved shape). In some examples, the reinforcing member 502 may be substantially concentric with the elongated tube 306.

[0340] In some examples, the length of the reinforcing member 502 may be approximately equal to the length of the slender tube 306.

[0341] In some examples, the reinforcing member 502 may be substantially inextensible when in use or when subjected to forces of up to about 10 Newtons (N), up to about 20 N, or up to about 45 N. A substantially inextensible reinforcing member 502 may be necessary in some applications where changes in the length of the expiratory conduit 146 may not be desired.

[0342] In other examples, the reinforcing member 502 may be elastically stretchable during use or when subjected to a force of up to about 10 N, up to about 20 N, or up to about 45 N. The elastically stretchable reinforcing member 502 may allow the elongated tube 306 to partially expand in the longitudinal direction, which may improve the air permeability of the elongated tube 306.

[0343] The reinforcing member 502 may include a longitudinal portion 702 configured to extend along at least a portion of the length of the elongated tube 306. The longitudinal portion 702 may be located approximately at the center of the inner cavity of the elongated tube 306.

[0344] The reinforcing member 502 may include a plurality of radial portions 704. Each radial portion 704 may extend outward from a longitudinal portion. The radial portions may position the longitudinal portion within the lumen (e.g., approximately at the center of the lumen). The radial portions 704 may improve one or more of the crush resistance or crush recovery of the corresponding portion of the expiratory conduit 146. Each radial portion 704 may each include a plurality of spokes (e.g., 3 to 5 spokes, or 4 spokes). The spokes may be circumferentially spaced apart.

[0345] In some examples, one or more radial portions of the radial portion 704 may engage with the elongated tube 306, for example, by friction fit or interference fit. The radial portion 704 may engage with the corrugations of the elongated tube 306 (e.g., the inner surface of the elongated tube at the inner trough). Such engagement can suppress relative movement between the reinforcing member 502 and the elongated tube 306 in the longitudinal direction and suppress expansion of the elongated tube 306 in the longitudinal direction.

[0346] In some examples, one or more radial portions of the radial portion 704 may be fixedly attached to the elongated tube 306, for example, by adhesive or welding. The attachment between the radial portion 704 and the elongated tube 306 may prevent at least a portion of the elongated tube 306 from expanding in one or more of the radial or longitudinal directions.

[0347] In some examples, one or more radial portions of the radial portions 704 may engage with connectors 302, 304. Radial portions 704 at each end of the reinforcing member 502 may engage with a corresponding one of connectors 302, 304. These end radial portions 704 may differ from the radial portions 704 that engage with the elongated tube 306.

[0348] Figure 8 This is a detailed view of another example expiratory cannula, including reinforcing components, presented in a schematic form.

[0349] The reinforcing member 502 in this example is an external reinforcing member. The reinforcing member 502 is disposed around the elongated tube 306. The reinforcing member 502 may have a helical shape (e.g., a double helix structure).

[0350] In some examples, the external reinforcement 502 can suppress the expansion of at least a portion of the elongated tube 306 in both the radial and longitudinal directions.

[0351] The reinforcing member 502 can bias the expiratory conduit 146 (e.g., the elongated tube 306) toward a predetermined length. This is similar to... Figure 5 Reinforcing components.

[0352] In some examples, the reinforcing member 502 may be spaced apart from the elongated tube 306 (e.g., when the elongated tube 306 is in one or more of a dry or equilibrium state). That is, the reinforcing member 502 does not fit tightly against the outer surface of the elongated tube. This spacing allows the elongated tube 306 to expand relatively freely in the radial direction before the reinforcing member 502 inhibits further expansion.

[0353] In other examples, the reinforcing member 502 may fit tightly against the outer surface of the elongated tube 306, or at least against the outer surface of the outer crest of the corrugated elongated tube 306. The reinforcing member 502 may be elastic, thereby allowing the elongated tube 306 to expand at least partially in the radial direction.

[0354] although Figure 8 Not shown, but the exhalation tubing may include connectors 302 and 304. The respective ends of the reinforcing member 502 may be securely attached to connectors 302 and 304. In some examples, the reinforcing member 502 is not securely attached to the elongated tube 306 at all. In other examples, the reinforcing member 502 may be securely attached to the elongated tube 306 at one, two, three, or more discrete locations or continuously.

[0355] In some examples, the reinforcing member 502 may be formed at least in part from a polymeric material such as polypropylene.

[0356] Figure 9This is a detailed view of another example expiratory cannula, including reinforcing components, presented in a schematic form.

[0357] In this example, reinforcement member 502 is an external reinforcement member.

[0358] The reinforcing member 502 may include a plurality of annular members 902. The annular members 902 may extend around the circumference of the elongated tube 306. The annular members 902 may be substantially coaxial with the elongated tube 306 and / or with each other. One or more of the annular members 902 may be configured to engage, for example, with one or more corrugations of the corrugated elongated tube 306 in an interference fit. The annular members 902 may at least partially occupy the outer troughs between successive outer crests of the corrugated elongated tube 306. The engagement between the annular members 902 and the corrugations may suppress relative movement in the longitudinal direction, which may suppress expansion of at least a portion of the elongated tube in the longitudinal direction (e.g., between adjacent annular members 902).

[0359] In some examples, the reinforcing member 502 may have 10 to about 200 annular members 902. In some examples, the reinforcing member 502 has one annular member 902 between every 2 to 50 corrugations, or between every 4 to 40 corrugations, of the elongated tube 306. In some examples, the elongated tube 306 may have 400 to 450 corrugations, or 410 to 430 corrugations, for example, 418 corrugations. Furthermore, the reinforcing member 502 may have 2 to 209 annular members 902, or 8 to 100 annular members 902.

[0360] The annular member 902 can suppress at least a portion of the slender tube 306 from expanding in the radial direction.

[0361] The reinforcing member 502 may include a plurality of longitudinal members 904. Each longitudinal member 904 may extend and be spaced apart between adjacent pairs of annular members 902. In some examples, there may be one to eight longitudinal members 904, or two to four longitudinal members 904, between each pair of consecutive annular members 902. The longitudinal members 904 may be rotatably biased between two or more adjacent pairs of the plurality of annular members. The longitudinal members 904 may have a smaller cross-sectional area than the annular members 902.

[0362] Multiple longitudinal members 904 can suppress the expansion of at least a portion of the elongated tube 306 in the longitudinal direction. Multiple longitudinal members 904 can suppress the expansion of at least a portion of the elongated tube 306 in the radial direction.

[0363] The annular member 902 and the longitudinal member 904 together can form a perforated structure. The perforated structure may include multiple openings 906. The openings 906 can allow water molecules to evaporate from the breathable material of the elongated tube 306 into the ambient air. In some examples, the perforated structure may be configured to expose at least about 25%, at least about 50%, at least about 75%, or at least about 85% of the elongated tube 306 to the ambient air 108.

[0364] In some examples, the reinforcing member 502 may be formed at least partially of an elastic material (e.g., an elastomeric material).

[0365] In some examples, when the expiratory conduit 146 is in one or more of a dry or balanced state, the reinforcing member 502 may at least partially conform closely to the outer surface of the elongated tube 306, or at least closely conform closely to the outer crest of the corrugated elongated tube 306. In other examples, when the expiratory conduit 146 is in one or more of a dry or balanced state, at least a portion of the reinforcing member 502 may be spaced apart from the elongated tube 306 around its circumference.

[0366] Figure 10 This is a detailed view of another example expiratory cannula, including reinforcing components, presented in a schematic form.

[0367] In this example, reinforcement member 502 is an external reinforcement member. Reinforcement member 502 may be in the form of a sheath. Reinforcement member 502 may be a non-woven reinforcement member.

[0368] Figure 10 The expiratory tube 146 is shown in a balanced state (e.g., before use).

[0369] In some examples, the reinforcing member 502 may be a malleable reinforcing member, for example, at least partially formed of a malleable material such as a malleable alloy. The malleable alloy may be coated with a polymeric material (e.g., an elastomeric polymeric material). The polymeric material may be overmolded onto the malleable alloy. The malleable reinforcing member 502 may be self-supporting. The reinforcing member 502 may be manipulated by a user to provide a constrained route for the elongated tube 306. The reinforcing member 502 may be manipulated to change the degree to which expansion of the elongated tube 306 in different regions of the expiratory conduit 146, for example, in the radial direction. For example, in one region, the reinforcing member 502 may be manipulated to fit tightly against the elongated tube 306 (e.g., when it is in equilibrium). In a second region, the reinforcing member 502 may be manipulated such that it is at least partially spaced from the outer surface of the elongated tube 306. Therefore, expansion of the elongated tube 306 in the radial direction may be better suppressed in the first region compared to the second region.

[0370] In some examples, the reinforcing member 502 may be at least partially formed of a shape memory material (e.g., a shape memory alloy or shape memory polymer). The reinforcing member 502 may deform due to temperature changes in the elongated tube during use. Heating the elongated tube allows the shape memory material to be heated to produce deformation. The reinforcing member 502 can recover its "memory" shape when heated. In some examples, the shape memory material may be configured to exhibit a shape that allows the elongated tube 306 to expand more in one region (e.g., inlet region 402) than in another region, for example, in the radial direction.

[0371] Figure 11 Examples of those in a state of adjustment are shown. Figure 10 The expiratory tube 146, for example, as may occur after a period of use. Local bulging can be observed in the inlet region 402 near the connector 302.

[0372] The reinforcing member 502, formed of a ductile material, can be manipulated to allow for localized expansion (e.g., if condensation or other liquid accumulation is observed in the area). In other examples, the reinforcing member 502 may be configured to deform due to the expansion of the elongated tube 306.

[0373] When in use, the reinforcing member 502, formed of shape memory material, can restore its "memory" shape when subjected to the heat of breathing gas delivered by the elongated tube 306.

[0374] Core suction

[0375] In some examples, the internal reinforcement 502 may be configured to suck condensate or other liquids into the inner cavity of the wicking tube 306 during use.

[0376] The reinforcing member 502 may include one or more grooves. These grooves may provide wicking at least partially via capillary action. Forming one or more grooves in the reinforcing member 502 provides a narrow path that can be configured to transport liquid via capillary action. This capillary wicking may be caused by the adhesive forces between the liquid and the surface, as well as the surface tension of the liquid. The wicking effect may also be influenced by external forces such as gravity. The capillary force may be sufficient to counteract gravity and wick the liquid a considerable distance.

[0377] Improving the wicking performance of the reinforcing member 502 can be achieved by changing or altering the size and / or shape of the groove. In some examples, the groove may extend as deep as possible into the reinforcing member 502 to increase the surface area and / or cross-sectional area of ​​the groove. The depth may be limited by the dimensions of the reinforcing member 502. The depth of the groove formed in the reinforcing member 502 may be selected to maintain the structural integrity of the reinforcing member 502 and / or the expiratory conduit 146.

[0378] In some examples, the groove can be relatively narrow compared to the depth in order to maintain a high surface area to volume ratio. For capillary wicking, such a configuration can increase one or more of the speed at which liquid is transported along the groove or the distance (e.g., height) that liquid can be transported.

[0379] In some examples, the groove can be relatively wide compared to its depth. Having a wider groove can offer benefits in terms of the volume of liquid transported via capillary wicking. Although the velocity may not be as fast as with a narrower groove, the increased cross-sectional area of ​​the groove provides a larger total flow rate. This can be useful for redistributing larger volumes of liquid, where the total flow rate may be more important than the total wicking velocity and / or distance.

[0380] Further details of the wicking are disclosed in International Patent Application Publication No. WO 2019 / 203664 A1, the entire contents of which are incorporated herein by reference.

[0381] Figure 12 An isometric view of another example expiratory cannula 146 is shown.

[0382] The expiratory tube 146 is shown in equilibrium. Not shown to scale.

[0383] The expiratory cannula 146 in this example includes a braided sheath 1202. The braided sheath 1202 is disposed around the outer surface of the elongated tube 306. The braided sheath can be configured to loosely fit around the elongated tube 306, for example, not engaging the entire circumference of the elongated tube 306 in a balanced state.

[0384] One or more of connectors 302 and 304 may include one or more apertures (e.g., a pair of apertures 1204). In some examples, such as Figure 12 As shown, each connector includes only two apertures 1204 (i.e., a single pair of apertures 1204). The apertures 1204 may extend through the cylindrical wall of the connector. The apertures may be radial apertures. One or more of an elongated tube 306 or a braided sheath 1202 may be exposed through the apertures 1204. The pair of apertures 1204 may be arranged diametrically opposed. The size and / or shape of the pair of apertures 1204 may be identical to each other. The pair of apertures 1204 may, in combination, extend beyond 80% or 90% of the circumference of the respective connectors 302, 304.

[0385] Connectors 302 and 304 may be generally cylindrical. A distal portion of the connector (e.g., connector 302) may extend distally toward the elongated tube 306. The distal portion may include a conical connector as described above. The distal portion may be configured to establish and maintain a pneumatic connection with one or more of the Y-shaped element 142, the gas source 104, or optionally a filter. A proximal portion of the connector (e.g., connector 302) may extend around and / or within the end of one or more of the elongated tube 306 or the braided sheath 1202. The proximal portion may be configured to secure the connector to the elongated tube 306. In some examples, the proximal portion of the connector extends around and within the end of the elongated tube 306 and the braided sheath 1202. One or more of the elongated tube 306 or the braided sheath 1202 may be secured (e.g., clamped) within the proximal portion of the connector (e.g., between the exterior and interior of the proximal portion). The orifice 1204 may be located in the proximal portion (e.g., the exterior of the proximal portion).

[0386] The braided sheath 1202 is securely attached to the slender tube 306 via connectors 302 and 304. Figure 12 (The braided sheath in the middle is used for shielding). Connectors 302 and 304 may at least partially overmolded onto the braided sheath 1202 and the elongated tube 306.

[0387] One or more of connectors 302 and 304 may be formed of two parts. A first part may be injection molded. A second part may be overmolded. The second part may be overmolded to the first part, the elongated tube 306, and the braided sheath 1202. The first part may form at least the interior of the proximal portion. The second part may form at least the exterior of the proximal portion. An aperture 1204 may be located in the second part. The aperture 1204 may form a through-hole in the second part, but a blind hole in the entire connector assembly and / or conduit.

[0388] The orifice 1204 can advantageously allow at least two or more of the elongated tube 306, the braided sheath 1202, and the first component of the connector to be clamped together, for example, in a mold, when the second part is overmolded.

[0389] In some examples, such as Figure 12 As shown, the braided sheath 1202 is not attached to the elongated tube 306 between connectors 302 and 304. In other examples, as described above, an intermediate connector may be present that is attached to both the braided sheath 1202 and the elongated tube 306.

[0390] The length and diameter of the braided sheath 1202 can be negatively correlated. For example, as the braided sheath 1202 becomes longer, it becomes narrower.

[0391] tethering

[0392] In some examples, a medical gas catheter may be at least partially tethered to another medical gas catheter.

[0393] Figure 13 It shows Figure 4 and Figure 5 The expiratory tube 146 is attached to the inspiratory tube 130 of the respiratory support system 100.

[0394] In some examples, the inspiratory conduit may include a pair of connectors 1302, 1304 and an elongated tube 306, similar to the expiratory conduit 146.

[0395] The elongated tube 1306 of the inspiratory conduit may be formed of a non-permeable material (e.g., a polyolefin, such as polyethylene or polypropylene). That is, the elongated tube 1306 is not formed of a permeable material. Such materials tend not to expand during use, or expand only negligibly in one or more of the radial or longitudinal directions during immersion testing, for example, less than 5% or less than 1%. In some examples, the permeability of the elongated tube 1306 of the inspiratory conduit 130 may be lower than that of the elongated tube 306 of the expiratory conduit 146. In some examples, the elongated tube 1306 of the inspiratory conduit 130 may expand less during use than the elongated tube 306 of the expiratory conduit 146.

[0396] The expiratory tubing 146 can be configured to expand more in the longitudinal direction than the inspiratory tubing 130 when in use. The difference in expansion can be observed with the naked eye.

[0397] The expiratory conduit 146 (e.g., elongated tube 306) can be attached to the inspiratory conduit 130 (e.g., elongated tube 1306) via one or more retainers 1308. In some examples, there may be 2 to 120 retainers 1308, 3 to 60 retainers 1308, or 4 to 40 retainers 1308. In some examples, one retainer may be present for every 4 to 50 corrugations of the expiratory conduit 146.

[0398] In some examples, as illustrated, retainers 1308 may be separable from each other. In other examples, as described below, two or more retainers of retainers 1308 may be physically connected to each other or may be connected to each other.

[0399] Each retainer in retainer 1308 may be integrally formed, for example, by injection molding.

[0400] Retainers 1308 may be spaced apart along the length of the inspiratory conduit 130 and the expiratory conduit 146, or may be configured to be spaced apart along the length of the conduit. In some examples, at least some retainers of retainers 1308 may be spaced apart at equal intervals. In some examples, the spacing between at least some retainers of retainers 1308 may be varied.

[0401] The retainer 1308 can be positioned such that the inhalation conduit 130 and the exhalation conduit 146 can branch at one end to connect to the humidifier 102 and the gas source 104, respectively.

[0402] Each retainer in retainer 1308 is capable of being detachably engaged and re-engaged with a corresponding portion of each of inspiratory conduit 130 and expiratory conduit 146, and can maintain at least a corresponding portion of inspiratory conduit 130 and expiratory conduit 146 in a side-by-side relationship.

[0403] The retainer 1308 may engage with the inspiratory conduit 130 and the expiratory conduit 146 in a manner that inhibits longitudinal movement relative to the retainer 1308, and may also inhibit the inspiratory conduit 130 or the expiratory conduit 146 from sliding through the retainer 1308. In some examples, the retainer 1308 may engage with a corrugation (e.g., an outer trough) in one or more of the inspiratory conduit 130 or the expiratory conduit 146 in an interference fit. In some examples, the retainer 1308 may engage with one or more of the inspiratory conduit 130 or the expiratory conduit 146 in a friction fit.

[0404] The retainer 1308 and the inspiratory conduit 130 together can inhibit at least a portion of the expiratory conduit 146 (e.g., located between adjacent retainers 1308) from expanding in the longitudinal direction.

[0405] The retainer 1308 can inhibit radial expansion of the elongated tube 306 by substantially surrounding at least a large portion of its circumference. In some examples, at least in the equilibrium state, the retainer 1308 can loosely fit around the circumference of the elongated tube 306. This allows the elongated tube 306 to partially expand radially before further expansion is inhibited. In other examples, in the equilibrium state, the retainer 1308 can fit tightly against the circumference of the elongated tube 306, or even apply a slight compressive force to hold the elongated tube 306.

[0406] like Figure 13 As shown, the expiratory tubing 146 can expand radially between adjacent pairs of retainers 1308. In some examples, retainers 1308 may also allow partial radial expansion within retainers 1308.

[0407] The retainer 1308 improves the crush resistance of at least a portion of the expiratory tube 146. The crush resistance can be further improved by increasing the number or density of the retainers 1308.

[0408] The inspiratory conduit 130 can improve the crush resistance of the expiratory conduit 146. For example, the crush resistance of the inspiratory conduit 130 can limit the compressive force applied to the adjacent expiratory conduit 146. The combined crush resistance of the inspiratory conduit 130 and the expiratory conduit 146 can be greater than that of the expiratory conduit 146 alone.

[0409] In use, tying the inspiratory conduit 130 and the expiratory conduit 146 together provides some passive heating to the expiratory conduit 146. Passive heating is provided by a stream of heated and humidified respiratory gases delivered by the inspiratory conduit 130 and / or its heater wire 136. Passive heating reduces the formation of condensation within the lumen of the expiratory conduit 146. In some examples, the retainer 1308 may be at least partially formed of a thermally conductive material such as a metal alloy (e.g., aluminum alloy). In other examples, the retainer 1308 may be formed of a polymeric material such as a polyolefin (e.g., polyethylene or polypropylene).

[0410] Attaching the inspiratory tube 130 and the expiratory tube 146 together is neater and less invasive than allowing the inspiratory tube 130 and the expiratory tube 146 to hang independently.

[0411] In some examples, as illustrated, the inspiratory conduit 130 and the expiratory conduit 146 may be spaced apart from each other. This spacing allows the expiratory conduit 146 to expand more radially and / or improves permeability by exposing a larger surface area of ​​the elongated tube 306 to ambient air. In other examples, the inspiratory conduit 130 and the expiratory conduit 146 may be arranged close to each other, or even abutting against each other. Abutting against each other provides improved heat transfer from the inspiratory conduit 130.

[0412] The number of retainers 1308 used may depend on one or more of the following factors: the length of the catheters 130 and 146, the width of the retainer 1308, the absorption or expansion potential of the expiratory catheter 146, or the rigidity of the inspiratory catheter 130.

[0413] The retainer 1308 may be provided with one or more of the inspiratory tube 130 and / or expiratory tube 146 in the breathing circuit kit. In some examples, the retainer 1308 may be pre-assembled with one or more of the inspiratory tube 130 and / or expiratory tube 146.

[0414] Figure 14 Detailed views of an inspiratory tube 130, an expiratory tube 146, and a plurality of retainers 1308 according to another example are shown.

[0415] In some examples, such as Figure 14 As shown, each retainer in retainer 1308 may be exactly the same or substantially the same.

[0416] Each retainer in retainer 1308 may include a pair of retaining members. In some examples, each retaining member in the pair may be a clip 1402. One retaining member in the pair may be configured to extend around inspiratory conduit 130 (e.g., elongated tube 1306). The other retaining member in the pair may be configured to extend around expiratory conduit 146 (e.g., elongated tube 306). Thus, each retainer 1308 is configured to independently retain inspiratory conduit 130 and expiratory conduit 146. This independence allows a healthcare professional to remove and / or replace one of the conduits if needed. However, in other examples, retainers 1308 may each include a single retaining member configured to extend around both inspiratory conduit 130 and expiratory conduit 146.

[0417] Clip 1402 may be partially annular. Clip 1402 may define an opening 1404 through which corresponding conduits 130, 146 (e.g., elongated tubes 1306, 306) may be received in an internal portion. Clip 1402 may be configured such that one or more of clip 1402 or elongated tubes 1306, 306 elastically deform when elongated tubes 1306, 306 are forced through opening 1404. Clip 1402 may partially or completely recover. The openings 1404 of the pair of clips 1402 may face opposite directions. In some examples, the pair of clips 1402 may be identical (e.g., mirror images of each other). In other examples, the pair of clips 1402 may be different, for example, to accommodate different inspiratory conduits 130 and expiratory conduits 146, such as elongated tubes 1306 and 306.

[0418] Each clamp in clamp 1402 may branch outward adjacent to opening 1404. This branching may help guide the catheter to and through opening 1404.

[0419] In some examples, one or more protrusions may project inward from the inner surface of the clip 1402. The protrusions may be configured to at least partially occupy the outer troughs between adjacent outer crests of the corrugated elongated tube 306. The protrusions may inhibit or prevent relative movement in the longitudinal direction between the clip 1402 and the inspiratory or expiratory tube 130, and optionally, still allow partial expansion of the tube in the radial direction. Alternatively, the engagement surface of the retainer 1308 may be shaped to complement the corrugated profile of the expiratory tube 146.

[0420] In other examples, each retaining member in the retaining structure may include a strap. The strap may be configured to wrap around a corresponding one of the conduits 130, 146. Each strap may be secured by a fastener (e.g., a hook-and-loop fastener).

[0421] In some examples, at least some of the retaining members may be resilient retaining members. Resilient retaining members may be configured to deform during use to allow the expiratory conduit 146 to partially expand in the radial direction, but still at least partially inhibit expansion, or inhibit expansion in the longitudinal direction.

[0422] In some examples, at least some of the retaining members may be adjustable; for example, the retaining members are configured to receive and retain the expiratory conduit 146. This allows a user to adjust each retaining member to allow the expiratory conduit 146 to expand more or less radially in one or more regions of the expiratory conduit 146.

[0423] Figure 15 Shown separately Figure 14 An isometric view of a pair of retainers 1308.

[0424] Two or more retainers 1308 may be directly and physically connected to each other. Each retainer 1308 may include a first connector and a second connector. The first connector of one retainer 1308 may be configured to establish a mechanical connection with the second connector of another retainer 1308. In some examples, the mechanical connection may be one or more of a snap-fit ​​connection, a pivotable connection, or a ball-and-socket connection. A pivotable connection may have one or more degrees of freedom. A ball-and-socket connection may have three degrees of freedom.

[0425] In some examples, such as Figure 14 As shown, the first connector can be a ball connector 1502, and the second connector can be a socket 1504. The ball connector 1502 of one retainer 1308 can engage with the socket 1504 of the other retainer 1308 to establish a ball-socket connection.

[0426] In some examples, at least one of the multiple retainers 1308 may include only the first connector (i.e., excluding the second connector), and / or at least one of the multiple retainers 1308 may include only the second connector (i.e., excluding the first connector). A retainer 1308 having a single connector may be configured to be positioned at the respective end of a chain to which the retainer 1308 is connected.

[0427] In some examples, the mechanical connection may be configured to allow relative free movement between the two connected retainers 1308. This may allow one or more of the inspiratory conduit 130 or expiratory conduit 146 to bend freely during use, for example, to hang naturally between the Y-shaped member 142 and the gas source 104. In other examples, the mechanical connection may be configured to resist pivoting movement between the two connected retainers 1308 during use. This may allow manipulation of the retainers 1308 to at least partially define the constrained route of the inspiratory conduit 130 or expiratory conduit 146.

[0428] Figure 16 It shows Figure 15 A cross-sectional view of a pair of retainers 1308 shown.

[0429] The ball connector 1502 of one of the retainers 1308 is shown connected to the socket 1504 of the other retainer in the pair of retainers 1308.

[0430] Each retainer 1308 may include an arm 1602. The arm may be configured to space one retainer 1308 from another retainer, and specifically, to space a clip 1402 of one retainer 1308 from a clip 1402 of a retained retainer 1308 already connected. In some examples, the arm may be configured to define a fixed interval between adjacent pairs of retainers. A first connector (e.g., ball connector 1502) may be located at the distal end of arm 1602. A second connector (e.g., socket 1504) may be located at or near the proximal end of arm 1602. Clip 1402 may be located at or near the proximal end of arm 1602.

[0431] In some examples, multiple retainers may include at least one retainer 1308 without an arm. The retainer 1308 without an arm 1602 may be configured to be located at the end of the chain to which the retainer 1308 is attached, for example, such that there is no protruding arm that could potentially snag on, for example, bedding, clothing, furniture, or a person. The retainer 1308 may omit the arm 1602 and the first connector (e.g., ball connector 1502).

[0432] The ball-and-socket connection allows for a range of movement between the two retainers 1308. The range of movement can be selected to reduce the risk of kinking of one or more of the inspiratory or expiratory tubing 130 during use.

[0433] wavy profile

[0434] In some examples, medical gas conduits may be corrugated.

[0435] The corrugations may have a specific corrugation profile. The corrugation profile may differ from one or more of known medical gas catheters or inspiratory catheters 130. The modified corrugation profile may improve one or more of the rigidity, crush resistance, or crush recovery of the elongated tube 306, especially when the elongated tube 306 is in an adjusted or saturated state. The corrugation profile may prevent the expiratory catheter 146 from expanding in one or more of the radial direction, longitudinal direction, or wall thickness.

[0436] Figure 17 A detailed cross-sectional view of the elongated tube 306 of the exhalation cannula 146, for example, having an example corrugated profile when in equilibrium, is shown.

[0437] Each ripple may have an outer crest 1702. In some examples, as shown, the outer crest 1702 may be rounded. In some examples, the outer crest 1702 is not flat; for example, a cylindrical surface is not limited. The outer crest 1702 may have a first radius of curvature 1704.

[0438] Each corrugation may have an outer trough 1706. In some examples, as shown, the outer trough 1706 may be rounded. In some examples, the outer trough 1706 is not flat; for example, a cylindrical surface is not limited. The outer trough 1706 may have a second radius of curvature 1708. The second radius of curvature 1708 may be smaller than the first radius of curvature 1704.

[0439] Each corrugation may have an inner crest 1710. The inner crest 1710 may be located on the inner surface of the tube wall, opposite the outer trough 1706 on the outer surface of the tube wall. In some examples, as shown, the inner crest 1710 may be rounded. In some examples, the inner crest 1710 is not flat; for example, a cylindrical surface is not limited. The inner crest 1710 may have a third radius of curvature 1712. In some examples, the third radius of curvature 1712 may be approximately equal to the first radius of curvature 1704. In some examples, the third radius of curvature 1712 may be greater than the second radius of curvature 1708.

[0440] Each corrugation may have an inner trough 1714. The inner trough 1714 may be located on the inner surface of the tube wall, opposite the outer crest 1702 on the outer surface of the tube wall. In some examples, as shown, the inner trough 1714 may be rounded. In some examples, the inner trough 1714 is not flat; for example, a cylindrical surface is not limited. The inner trough 1714 may have a fourth radius of curvature 1716. In some examples, the fourth radius of curvature 1716 may be smaller than the first radius of curvature 1704. In some examples, the fourth radius of curvature 1716 may be approximately equal to the second radius of curvature 1708. In some examples, the fourth radius of curvature 1716 may be smaller than the third radius of curvature 1712.

[0441] In some examples, such as Figure 17 As shown, the cross-section of the pipe wall at the outer crest 1702 and inner trough 1714 can be similar to, for example, a mirror image of the cross-section of the pipe wall at the outer trough 1706 and inner crest 1710.

[0442] Each corrugation may have a pair of sidewalls 1718. The sidewalls 1718 may be substantially straight. The sidewalls 1718 may be angled to converge toward the corresponding outer crest / outer trough (or inner crest / inner trough). In some examples, the sidewalls 1718 may be angled 90° relative to the longitudinal direction, for example, between about ±60° and ±90°, or between about ±77.5° and ±90°.

[0443] In some examples, such as Figure 17 As shown, the shape of the ripple profile can be roughly in the form of a sine wave.

[0444] The corrugated profile can be substantially uniform along the length of the elongated tube 306. In other examples, the elongated tube 306 may include a composite corrugated profile. In an elongated tube 306 including a composite corrugated profile, the corrugated profile may vary along the length of the elongated tube 306, for example, differing between two or more regions of the elongated tube 306. This allows for customization of one or more of rigidity, crush resistance, crush recovery, or expansion for different regions of the elongated tube 306.

[0445] In some examples, the corrugations may have a specific pitch, for example, measured as the distance between successive outer crests of the corrugated elongated tube 306. The pitch of the expiratory conduit 146 may be smaller than the pitch of the inspiratory conduit 130. In other words, the expiratory conduit 146 may have more corrugations than the inspiratory conduit 130. A lower pitch can increase the number of sidewalls 1718, which can improve one or more of the rigidity, crush resistance, or crush recovery of the elongated tube 306, especially when the elongated tube 306 is in a regulated or saturated state. In some examples, the pitch of the expiratory conduit 146 (e.g., the elongated tube 306) in equilibrium may be between about 1 mm and 3.5 mm, between about 2 mm and 3.5 mm, or between about 2 mm and 3 mm. In some examples, the pitch of the expiratory conduit 146 in equilibrium may be smaller than the pitch of the inspiratory conduit 130.

[0446] although Figure 17 Not shown, but at least one end of the elongated tube 306 may be non-corrugated. At least one of connectors 302 and 304 may be securely attached to the non-corrugated end portion. In some examples, connectors 302 and 304 may at least partially overmolded onto the non-corrugated end portion of the elongated tube 306.

[0447] In some examples, the wall thickness of the elongated tube 306 may be substantially uniform along the length of the elongated tube 306 or at least between connectors 302, 304. In other examples, the wall thickness of the elongated tube 306 may vary along the length of the elongated tube 306, for example, between two or more different regions of the corrugation and / or elongated tube 306. This allows for customization of one or more of rigidity, crush resistance, crush recovery, or expansion for different regions of the elongated tube 306.

[0448] In some examples, such as in a dry state or an equilibrium state, the corrugated profile around the circumference of the elongated tube 306 may be uniform. The elongated tube 306 may have rotational symmetry about its axis.

[0449] In some examples, the elongated tube 306 may include one or more ribs located on one or more of its inner or outer surfaces. In some examples, one or more ribs (e.g., two ribs) may extend in a longitudinal direction. Two longitudinal ribs may be disposed on opposite sides of the elongated tube 306. In some examples, one or more ribs may extend in a circumferential direction.

[0450] Figure 18 A detailed cross-sectional view of the elongated tube 306 of the exhalation cannula 146, for example, having another example corrugated profile when in equilibrium, is shown.

[0451] In some examples, any one or more of the outer crest 1702, outer trough 1706, inner crest 1710, or inner trough 1714 may be flattened, for example, defining a cylindrical surface. In some examples, as shown, all four of the outer crest 1702, outer trough 1706, inner crest 1710, and inner trough 1714 may be flattened, for example, defining corresponding cylindrical surfaces. Flattened crests / troughs reduce the likelihood of the corrugations that could cause the elongated tube 306 to expand "rotate." Rotation is the pivoting of the various surfaces toward the "flattened" elongated tube 306.

[0452] exist Figure 18 In the example, sidewall 1718 can be relative to Figure 17 The example is set at a steeper angle (e.g., about ±80°). Compared to a shallower angle, a steeper angle can improve one or more of the rigidity or crush resistance of the elongated tube 306 (e.g., when the elongated tube 306 is in an adjustable state).

[0453] Figure 19 A detailed cross-sectional view of another possible corrugated profile of the expiratory cannula 146 when, for example, in a balanced state, is shown.

[0454] In this example, the outer peak 1702 is not flat; for example, it is not limited to a cylindrical surface. The outer peak 1702 has rounded corners.

[0455] In this example, the outer valley 1706 is flat, for example, defining a cylindrical surface.

[0456] In this example, the inner wave peak 1710 is flat, for example, defining a cylindrical surface.

[0457] In this example, the inner valley 1714 is not flat; for example, it is not limited to a cylindrical surface. The inner valley 1714 has rounded corners. The radius of curvature of the inner valley 1714 is smaller than the radius of curvature of the outer peak 1702.

[0458] Each corrugation may have an inner trough 1714. The inner trough 1714 may be located on the inner surface of the tube wall, opposite the outer crest 1702 on the outer surface of the tube wall. In some examples, as shown, the inner trough 1714 may be rounded. In some examples, the inner trough 1714 is not flat; for example, a cylindrical surface is not limited. The inner trough 1714 may have a fourth radius of curvature 1716. In some examples, the fourth radius of curvature 1716 may be smaller than the first radius of curvature 1704. In some examples, the fourth radius of curvature 1716 may be approximately equal to the second radius of curvature 1708. In some examples, the fourth radius of curvature 1716 may be smaller than the third radius of curvature 1712.

[0459] breathable membrane

[0460] In some examples, medical gas conduits may include a membrane that is at least partially formed of a breathable material.

[0461] Figure 20 A detailed view of an example expiratory catheter 146 including a membrane 2002 is shown.

[0462] The water vapor transmission rate (MVTR) of membrane 2002 is higher than that of a thicker tube wall formed from the same breathable material.

[0463] In some examples, membrane 2002 may be an external membrane. Membrane 2002 may be disposed around elongated tube 306. Membrane 2002 may form a sleeve around elongated tube 306. Membrane 2002 may be directly engaged (e.g., abutting) with elongated tube 306. Elongated tube 306 may be corrugated. In some examples, such as... Figure 20 As shown, for example, when the expiratory conduit 146 is in equilibrium, the membrane 2002 may at least partially conform to the outer surface of the permeable elongated tube 306, for example, conforming to the outer crests of the corrugated elongated tube 306, as illustrated. The membrane 2002 may hang between adjacent outer crests of the permeable elongated tube 306. This hanging increases the flexibility of the expiratory conduit 146. The membrane 2002 may at least partially adopt the corrugated profile of the elongated tube 306. In other examples, the membrane 2002 may be relatively taut.

[0464] The membrane 2002 may be thinner than the wall thickness of the elongated tube 306. In some examples, the wall thickness of the membrane 2002 may be less than about 200 micrometers (μm), less than about 100 μm, less than about 80 μm, less than about 60 μm, or less than about 40 μm, for example, about 20 μm. In some examples, the wall thickness of the membrane 2002 may be about 2% to 30% or about 5% to 20% of the wall thickness of the elongated tube 306 in a dry or equilibrium state.

[0465] One or more air gaps 2004 may be formed between the membrane 2002 and the elongated tube 306, for example, between the outer troughs of the membrane 2002 and the elongated tube 306. The gas within the air gap 2004 may be relatively still compared to the breathing gas flow within the elongated tube 306. The gas within the air gap 2004 may be relatively warm compared to ambient air. The gas within the air gap 2004 may at least partially thermally insulate one or more of the elongated tube 306 or the breathing gas flow within the elongated tube 306 from ambient air. This reduces the formation of condensation within the elongated tube 306.

[0466] In some examples, membrane 2002 may be securely attached to elongated tube 306 via connectors 302, 304. Connectors 302, 304 may be at least partially overmolded to membrane 2002 and elongated tube 306.

[0467] In some examples, the membrane 2002 is not otherwise fixedly attached to the permeable elongated tube 306, for example, between connectors 302, 304. In other examples, the membrane 2002 may be fixedly attached to the elongated tube 306 at one, two, three or more discrete locations along the length of the elongated tube 306 (e.g., at each outer crest or each other outer crest of the elongated tube 306), for example, by overmolding, adhesive, or welding. The attachment between the membrane 2002 and the elongated tube 306 may at least be at the attachment and, to a lesser extent, adjacent to or between the attachments, inhibit the radial expansion of the membrane 2002.

[0468] The elongated tube 306 and the membrane 2002 may be made of different materials.

[0469] The slender tube 306 can be at least partially made of, as described above, especially the references Figure 4 and Figure 5 The example describes the formation of a breathable material. In some examples, the breathable material of the elongated tube 306 may differ from that of the membrane 2002. The elongated tube 306 may define an inner lumen through which breathing gases flow.

[0470] In other examples, the elongated tube 306 may be at least partially formed of a non-permeable material. In some examples, the elongated tube 306 does not include a permeable material. Alternatively, the elongated tube 306 may be porous (e.g., perforated) to provide a pathway for water molecules to flow from the interior to the exterior of the elongated tube 306, for example, through a pore flow mechanism. From there, water molecules can pass through the permeable material of the membrane 2002 via a dissolution-diffusion mechanism. In such examples, the outer membrane 2002 may at least partially define an inner lumen through which breathing gases flow.

[0471] In some examples, membrane 2002 may provide properties similar to the external reinforcement member 502 described above. For example, in use, membrane 2002 may restrict the longitudinal expansion of the permeable elongated tube 306. Membrane 2002 may be substantially non-stretchable, for example, elongating by less than about 10% or less than about 5% when subjected to forces typically encountered in use.

[0472] In some examples, such as when the elongated tube 306 is formed of a non-permeable material, the elongated tube 306 can support the permeable membrane 2002, similar to the internal reinforcement member 502. The elongated tube 306 can be configured not to expand during use, or to expand negligibly in one or more of the radial or longitudinal directions during immersion testing, for example, less than 10%, less than 5%, or less than 1%. Compared to the membrane 2002, the elongated tube 306 can be relatively rigid, but still possess sufficient flexibility to allow the expiratory conduit 146 to bend (e.g., droop) under its own weight when in equilibrium. The elongated tube 306 can prevent the membrane 2002 from expanding in the longitudinal direction. The elongated tube 306 can prevent the membrane 2002 from expanding in the radial direction. The elongated tube 306 can improve the crush resistance of at least a portion of the membrane 2002.

[0473] In some examples, one or more of the elongated tube 306 or the membrane 2002 may be extruded. In some examples, the elongated tube 306 and the membrane 2002 may be co-extruded.

[0474] Figure 21 Cross-sectional details of another example expiratory cannula 146 are shown.

[0475] In some examples, such as Figure 21 As shown, membrane 2002 can be an inner membrane 2002. Membrane 2002 can be disposed inside the elongated tube 306. Membrane 2002 can form a liner within the elongated tube 306. Membrane 2002 can be directly engaged (e.g., abutting) with the elongated tube 306. In some examples, for example, when the expiratory conduit 146 is in a balanced state, membrane 2002 can at least partially conform to the inner surface of the elongated tube 306, for example, conform to the inner crest of the corrugated elongated tube 306. In some examples, such as Figure 21As shown, membrane 2002 may extend substantially directly between the inner corrugations of elongated tube 306; for example, the membrane may be relatively taut. In other examples, membrane 2002 may hang between adjacent inner corrugations of elongated tube 306. Membrane 2002 may at least partially adopt the corrugated profile of elongated tube 306.

[0476] When membrane 2002 is an internal membrane 2002, membrane 2002 can separately define an inner lumen through which breathing gas flows. The elongated tube 306 may not be exposed to the breathing gas flow at all.

[0477] The elongated tube 306 may be formed of a non-permeable material. Mechanical properties (e.g., one or more stiffnesses, strengths, or crush resistance of the non-permeable material) may not change, may change negligibly, or may change to a different degree than in the permeable elongated tube. The membrane 2002 may not need to constrain the elongated tube 306 because the elongated tube 306 formed of a non-permeable material may not significantly absorb water. Alternatively, the elongated tube 306 may be perforated. The perforations 2102 may, for example, provide a pathway for water molecules from the interior of the elongated tube 306 to the ambient air 108 via a pore flow mechanism (after passing through the membrane 2002 via a dissolution-diffusion mechanism).

[0478] Perforations 2102 may be provided through the tube wall at the outer crests and inner troughs of the corrugations. Perforations 2102 may be spaced apart around the circumference of the elongated tube 306 (e.g., spaced at equal intervals). In some examples, perforations 2102 may be provided through the tube wall at one or more of the outer troughs and inner crests of the elongated tube 306 or on its sidewall. In some examples, the diameter of the perforations may be between about 20 μm and 2 mm, between about 50 μm and 1.5 mm, or between about 100 μm and 1 mm.

[0479] One or more air gaps 2004 may be formed between the membrane 2002 and at least the inner trough of the elongated tube 306. In use, the air gaps 2004 may be filled with air from ambient air. The air within the air gaps 2004 may be relatively still compared to the breathing gas flow within the elongated tube 306. The air within the air gaps 2004 may be relatively warm compared to ambient air. Furthermore, the air within the air gaps 2004 may at least partially thermally insulate one or more of the membrane 2002 or the breathing gas flow within the membrane 2002 from ambient air. This reduces the formation of condensation within the membrane 2002.

[0480] The inner membrane 2002 may provide a relatively smooth inner pore (i.e., a lumen with relatively smooth walls) for the expiratory conduit 146. The smooth inner pore provides relatively low flow resistance and allows condensate or other fluids to drain from one or more of the patient or gas source 104 to, for example, the lower part of the expiratory conduit. The elongated tube 306 may provide physical protection to the inner membrane 2002, for example, against one or more of abrasion, cuts, or punctures. For example, for compliance purposes, the elongated tube 306 may inhibit radial expansion of the membrane 2002. However, radial expansion may be permitted to a certain extent, for example, to improve permeability. In use, the degree of radial expansion of the membrane 2002 may be determined at least in part by the corrugated profile (e.g., the depth of the corrugations) of the elongated tube 306. In use, the expansion of the membrane 2002 in the longitudinal and radial directions, combined with the positive pressure of the breathing gas flow, allows the membrane 2002 to at least partially adhere to the inner surface of the elongated tube 306, for example, in a regulated or saturated state.

[0481] The use of a membrane formed from a breathable material instead of a thicker, thinner tube 306 may have one or more of the benefits of reduced material costs, improved breathability, or faster balancing or adjustment of the exhalation cannula 146.

[0482] Fiber reinforcement

[0483] In some examples, medical gas conduits may be at least partially formed of composite materials. These composite materials may consist of a matrix material and a reinforcing material. The matrix material and the reinforcing material can provide synergistic properties.

[0484] Composite materials can improve one or more of the mechanical properties, manufacturability, sustainability, or permeability of medical gas catheters. Improved mechanical properties may include one or more of rigidity, strength, crush resistance, or pneumatic compliance. The use of reinforcing materials may result in minimal changes to one or more of the mechanical properties of the medical gas catheter during use.

[0485] The composite material can be a fiber-reinforced polymer (FRP). The composite material may include a polymer matrix and fiber reinforcements. The polymer matrix may be a breathable material. The breathable material may include block polymers as previously described. In addition to the fiber reinforcements, various fillers may be added to the polymer matrix.

[0486] Fiber reinforcements may include one or more synthetic fibers or natural fibers. For example, synthetic fibers may include one or more carbon fibers, glass fibers, or aramid fibers. Natural fibers may include one or more cellulose fibers, jute fibers, flax fibers, or hemp fibers. Using natural fibers can improve the sustainability of medical gas conduits. The choice of fiber reinforcement will depend on the use case and requirements of the composite material.

[0487] Fiber reinforcements may include one or more of continuous or discontinuous fibers.

[0488] In some examples, continuous fibers may span one or more dimensions of the medical gas catheter, such as length or circumference. In some examples, the average length of discontinuous fibers may be less than about 25 mm. In some examples, the average length of discontinuous fibers may be less than about 5 mm.

[0489] In some examples, the average diameter of the fiber reinforcement can be between approximately 3 μm and 20 μm.

[0490] In some examples, the aspect ratio of the discontinuous fibers (i.e., the ratio between the average diameter of the fiber reinforcement and the average length of the fiber reinforcement) is higher than the critical fiber length of the polymer matrix. Fiber reinforcements with lengths exceeding the critical fiber length can improve stress transfer between the fiber reinforcement and the matrix material. Fiber reinforcements with lengths exceeding the critical fiber length can improve the mechanical properties of medical gas conduits.

[0491] The fibers may include fiber sizing agents. Fiber sizing agents can be used to improve the processability or properties of the fiber reinforcement. The properties of the fiber reinforcement can be improved by increasing interfacial adhesion with the polymer matrix. The fiber sizing agent may depend on the polymer matrix material. In some examples, the fiber sizing agent may include alkoxysilane compounds.

[0492] In some examples, the volume fraction of the fiber reinforcement may be about 5% to 60%, about 10% to 50%, or about 20% to 40% of the elongated tube, in one or more of the dry or equilibrium states. In one example, the volume fraction of the fiber reinforcement may be about 30% of the elongated tube, in one or more of the dry or equilibrium states.

[0493] Continuous fibers can be arranged to span one or more dimensions of the medical gas conduit, such as length or circumference. In some examples, the continuous fibers can be provided as a fabric in which a polymer matrix is ​​added to form an elongated tube. The fabric can include woven, knitted, felted, or braided preforms. In some examples, a pultrusion process can be used to combine the fiber reinforcement with the polymer matrix.

[0494] In some examples, the arrangement of fiber reinforcements can be used to provide orthotropic mechanical properties. In some examples, the arrangement of fiber reinforcements along a given direction can increase stiffness and / or strength relative to forces applied along that direction.

[0495] In some examples, the continuous fibers may be arranged unidirectionally (e.g., in the longitudinal direction). In some examples, at least some (e.g., most) of the continuous fibers may extend to cover the entire length of the elongated tube 306. In some examples, the continuous fibers may be embedded in the wall of the elongated tube. The continuous fibers may follow the corrugated profile of the corrugated elongated tube 306.

[0496] In some examples, different layers of continuous fibers may be arranged in different directions within the laminate. For example, the fibers in the first layer may be arranged longitudinally (0°), the fibers in the second layer may be arranged circumferentially (90°), and / or the fibers in the third layer may be arranged in opposite helical directions (±45°). The laminate may comprise approximately 4 to 48 layers. In some examples, the laminate may be quasi-isotropic.

[0497] In some examples, continuous fibers may be partially embedded in the wall of the elongated tube 306. The continuous fibers may be substantially linear. Linear continuous fibers may extend from the wall of the corrugated elongated tube 306, for example, into the outer troughs between adjacent outer crests.

[0498] The fibers can be uniformly dispersed within the polymer matrix. In other examples, the fibers can be located on or near one or more of the inner or outer surfaces of the tube wall.

[0499] Discontinuous fibers may be arranged randomly or along one or more directions. In some examples, discontinuous fibers may be provided as fabrics or molding compounds, in which a polymer matrix is ​​added to form medical gas conduits. In some examples, discontinuous fibers may be compounded with a matrix material to form granules for extrusion processes to form elongated tubes. In some examples, the composite material may include more than one matrix material. In some examples, the material feedstock may include first granules and second granules, the first granules comprising a first matrix material and fiber reinforcement, and the second granules comprising a second matrix material.

[0500] Figure 22 A partial cross-sectional view of the slender tube 306 is shown. Figures 23 to 25 It shows Figure 22 Detail A of the slender tube 306 (in) Figure 23 and Figure 25 (in) and details B (in) Figure 24 A detailed schematic diagram (in the middle) shows different discontinuous fiber arrangements.

[0501] like Figure 23As shown, the fibers can be randomly arranged. Composites comprising randomly arranged discontinuous fiber reinforcements can provide isotropic properties. In some examples, the fibers can be arranged in a specific direction. In contrast to continuous fiber reinforcements, only a certain proportion of the discontinuous fiber reinforcements can be arranged in a given direction. In some examples, approximately 20% to 100% of the fibers can be arranged in a given direction. In some examples, up to approximately 80% of the fibers can be arranged in a given direction.

[0502] like Figure 24 As shown, the fibers can be arranged circumferentially following the corrugated profile of the tube wall.

[0503] like Figure 25 As shown, the fibers can be arranged in the longitudinal direction. In some examples, discontinuous fibers can be randomly arranged when used as raw materials (e.g., in granular form) and can be induced to achieve this arrangement during manufacturing (e.g., during extrusion to form elongated tubes 306).

[0504] Medical gas conduits comprising materials with isotropic properties may be advantageous. In some examples, the composite elongated tube 306 may comprise randomly arranged discontinuous glass fibers that meet the following criteria: an average length of at least 0.5 mm, between about 0.5 mm and 10 mm, or between about 1 mm and 5 mm, for example, about 1.5 mm or about 3 mm. The average diameter of the glass fibers may be between about 5 μm and 30 μm, or between about 10 μm and 20 μm, for example, about 15 μm. In one or more of the dry or equilibrium states, the glass fibers may form about 5% to 60%, about 10% to 50%, or about 20% to 40% of the elongated tube. In some examples, the composite elongated tube 206 comprising randomly arranged discontinuous glass fibers may have higher crush resistance than medical gas conduits that do not include fiber reinforcement. In some examples, the composite slender tube 306, which includes randomly arranged discontinuous glass fibers, exhibits a lower change in aerodynamic compliance between equilibrium and saturation states than an equivalent medical gas conduit excluding fiber reinforcement.

[0505] Surgical air-infusion system

[0506] The medical gas catheter according to this disclosure can be applied to any number of alternative medical gas systems. The surgical inhalation system is described below by way of example.

[0507] refer to Figure 26 An example surgical air delivery system 2600 is illustrated schematically. The surgical air delivery system 2600 can be configured to supply a stream of air to a patient's body cavity, such as the abdominal cavity or peritoneal cavity. For example, the stream of air may be supplied to a patient's body cavity during, for example, laparoscopic surgery.

[0508] The blown gas stream can be pressurized to above atmospheric pressure. When used by a surgeon or surgical team to perform surgery, the blown gas may create a workspace within the patient's body cavity. The surgery may involve burning that produces surgical fumes within the workspace.

[0509] The blown gas may include carbon dioxide. In some examples, the blown gas may include a pharmaceutical agent.

[0510] In some examples, the temperature of the blown gas received by the surgical blow-in system 2600 may be less than about 25 degrees Celsius (°C), less than about 23°C, less than about 21°C, or approximately equal to or below room temperature. In some examples, the relative humidity of the blown gas received by the surgical blow-in system 2600 may be less than about 20%, less than about 10%, or less than about 5%. Heating and humidifying the blown gas can reduce cell damage or dehydration, limit adhesion formation, or reduce other harmful effects.

[0511] The surgical air delivery system 2600 may include a gas source 2602.

[0512] In some examples, gas source 2602 may include wall source 2604 or compressed gas cylinder 2606. In some examples, gas source 2602 may include a pressure generator (e.g., a blower) configured to pressurize ambient air. In some examples, gas source 2602 (e.g., a pressure generator) may be integrated with an inlet.

[0513] The surgical air-injection system 2600 may include an air-injector supply catheter 2608.

[0514] The insufflator supply conduit 2608 may be configured to receive an insufflator gas flow from the gas source 2602. The insufflator supply conduit 2608 may be configured to deliver the insufflator gas flow to downstream components (e.g., insufflators) of the surgical insufflator system 2600.

[0515] The insufflator supply conduit 2608 may include a pair of connectors configured to connect the insufflator supply conduit 2608 to one or more other components of the surgical insufflation system 2600 (e.g., gas source 2602 and insufflator).

[0516] The inhaler supply conduit 2608 may otherwise be substantially similar (e.g., structurally and / or functionally similar) to, for example, the humidifier supply conduit 116 of the respiratory support system 100, as described above.

[0517] The surgical air delivery system 2600 may include an air delivery device 2610.

[0518] Insulator 2610 may be configured to receive an insulated gas flow from insulated gas supply conduit 2608. Insulated gas 2610 may be configured to control the pressure of the insulated gas flow. Insulated gas 2610 may be configured to supply a pressure-controlled insulated gas flow to downstream components of surgical insulated gas system 2600 (e.g., humidifier supply conduit).

[0519] In some examples, the insufflator 2610 can be configured to supply an insufflation flow at a pressure of approximately 5 mm / Hg to 20 mm / Hg. The pressure selected may depend on the patient's size and the required inflation volume.

[0520] In some examples, the blower 2610 can be configured to supply a blow-in gas flow at a rate of approximately 1 L / min to 12 L / min. The selected flow rate may depend on the requirements of the specific operation.

[0521] In some examples, the blower 2610 may include a proportional solenoid valve (PSV). The proportional solenoid valve may be operable to control the pressure of the blow-in gas flow supplied to downstream components of the surgical blow-in system 2600. In other examples, the blower 2610 may be integrated with a gas source 2602, such as a pressure generator including a blower. The pressure generator may be operable to generate the blow-in gas flow (e.g., by pressurizing ambient air).

[0522] The blower 2610 may include one or more sensors, such as a pressure sensor configured to sense the pressure of the blown gas flow or a flow rate sensor configured to sense the flow rate of the blown gas flow.

[0523] The blower 2610 may include a user interface. The user interface may be configured to display information to a user. The user interface may include a display (e.g., an LCD or OLED display). The user interface may be configured to receive input from the user, for example, via one or more of a button, switch, dial, or touchscreen display. Input may include the desired pressure of the blown gas flow supplied to the patient.

[0524] The blower 2610 may include a blower controller. The blower controller may be configured to control the flow rate of the blown gas (e.g., the pressure of the blown gas flow). The blower controller may control a proportional solenoid valve or a pressure generator. The blower controller may receive input from one or more sensors or a user interface. The blower controller may include one or more processors. The blower controller may include a machine-readable medium (e.g., non-transitory memory). The machine-readable medium is programmable with instructions that, when executed by one or more processors, cause the blower 2610 to operate as described herein. The blower controller may be configured to control the gas source 104 at least in part based on input received from the user interface. The blower controller may be configured to control the blower 2610 at least in part based on input received from one or more sensors. The blower controller may be configured to control the blower 2610 using closed-loop control (e.g., using a proportional-integral-derivative (PID) control algorithm).

[0525] The surgical air delivery system 2600 may include a humidifier supply conduit 2612.

[0526] The humidifier supply conduit 2612 may be configured to receive a stream of blown gas from the blower 2610. The humidifier supply conduit 2612 may be configured to deliver the stream of blown gas to downstream components (e.g., humidifiers) of the surgical blow-in system 2600.

[0527] In other examples (e.g., surgical airflow systems configured for open surgery), the humidifier supply conduit 2612 may be configured to receive, for example, an airflow from the gas outlet port of a carbon dioxide (CO2) gas supply station, either directly or via an airflow gas filter.

[0528] The humidifier supply conduit 2612 may otherwise be substantially similar (e.g., structurally and / or functionally similar) to one or more of the humidifier supply conduit 116 of the respiratory support system 100 or the insufflation conduit 2608 of the surgical insufflation system 2600, as described above.

[0529] The surgical air delivery system 2600 may include a humidifier 2614.

[0530] The humidifier 2614 can be configured to heat and / or humidify the incoming gas stream.

[0531] Humidifier 2614 may be configured to receive a stream of blown gas from humidifier supply conduit 2612. Humidifier 2614 may be configured to supply a heated and / or humidified stream of blown gas to downstream components of surgical air delivery system 2600 (e.g., delivery conduit).

[0532] In some examples, the humidifier 2614 can be configured to humidify the incoming gas stream to or near saturation, for example, about 100% relative humidity.

[0533] In one example, the humidifier 2614 could be an F&P HumiGard purchased from Fisher & Paykel Healthcare Limited in Auckland, New Zealand. ™ SH870 Surgical Humidifier.

[0534] A funnel can be provided to assist in filling the humidifier (e.g., humidification chamber) with humidifying liquid (e.g., sterile water).

[0535] Humidifier 2614 may otherwise be substantially similar to (e.g., structurally and / or functionally similar to) humidifier 102 of respiratory support system 100.

[0536] In other examples, the humidifier may be omitted from the surgical airflow system. Alternatively, the humidifier 2614 may be disabled. The surgical airflow system may supply the patient with a relatively dry airflow, for example, with a relative humidity below about 80%, below about 60%, or below about 50%.

[0537] The surgical air-blowing system 2600 may include a delivery catheter 2616.

[0538] The delivery conduit 2616 may be configured to receive a stream of blown gas from the humidifier 2614. The delivery conduit 2616 may be configured to deliver the stream of blown gas to a downstream component (e.g., a surgical cannula) of the surgical air delivery system 2600.

[0539] In some examples, the delivery catheter 2616 may be configured to connect to a surgical cannula. The delivery catheter 2616 may include a Luer lock connector (e.g., located at the outlet end of the delivery catheter 2616). The Luer lock connector may be configured to connect directly to the surgical cannula.

[0540] In some examples (e.g., surgical air-blowing systems configured for open surgery), the delivery catheter 2616 may be configured to connect to a diffuser.

[0541] The delivery catheter 2616 may otherwise be substantially similar (e.g., structurally and / or functionally similar) to one or more of the inspiratory catheter 130 of the respiratory assist system 100, or the insufflation supply catheter 2608 or the humidifier supply catheter 2612 of the surgical insufflation system 2600, as described above.

[0542] The surgical air-injection system 2600 may include a surgical cannula 2618.

[0543] The surgical cannula 2618 can be configured to receive a flow of inhaled gas from the delivery catheter 2616. The surgical cannula 2618 can be configured to engage with a Luer lock connector of the delivery catheter 2616. The surgical cannula 2618 can be configured to supply a flow of inhaled gas to the patient's body cavity.

[0544] The surgical cannula 2618 can be configured to receive surgical instruments (e.g., endoscopes). Figure 26 The endoscope 2620 and laparoscopic monitor 2622 are also shown. The endoscope 2620 and laparoscopic monitor 2622 can be part of a wider surgical system.

[0545] The surgical air intake system 2600 may include one or more air intake gas filters.

[0546] In some examples, the blow-in gas filter may be disposed between the blower 2610 and the humidifier 2614, for example, directly between the outlet of the blower 2610 and the inlet end of the humidifier supply conduit 2612. In some examples, the blow-in gas filter may be disposed between the humidifier 2614 and the surgical cannula 2618, for example, directly between the outlet of the humidifier 2614 and the inlet end of the delivery conduit 2616.

[0547] The surgical air delivery system 2600 may include a smoke extraction system 2624.

[0548] The smoke extraction system 2624 can be configured to receive an inhaled gas stream and surgical smoke (if any) from the patient's body cavity. In some examples, the smoke extraction system 2624 may receive the inhaled gas stream and surgical smoke via a surgical cannula 2618. In other examples, the smoke extraction system 2624 may receive the inhaled gas stream and surgical smoke (if any) via a ventilator. The smoke extraction system 2624 can be configured to connect to one or more of the surgical cannula 2618 or the ventilator. The smoke extraction system 2624 can be configured to deliver the inhaled gas stream and surgical smoke away from the patient.

[0549] The smoke exhaust system may include one or more of an exhaust duct 2626, an exhaust filter 2628, or another exhaust duct 2630.

[0550] The discharge conduit 2626 may be configured to connect to one or more of the surgical cannula 2618 or the ventilation cannula. The discharge conduit 2626 may be configured to connect to the discharge filter 2628. In some examples, the discharge conduit 2626 may be configured to connect to a vacuum source 2632.

[0551] The exhaust filter 2628 may be configured to filter, for example, a stream of blown gas and surgical fumes (if present) received from a patient's body cavity via an exhaust conduit 2626. The exhaust filter 2628 may include a filter media. The filter media may be configured to capture contaminants in the blown gas stream or surgical fumes. Contaminants may include one or more of particulate matter, odors, or gaseous hydrocarbons. In some examples, the filtered blown gas stream downstream of the exhaust filter 2628 may be approximately 100% blown gas (e.g., carbon dioxide). In some examples, the exhaust filter may remove 99.999% of all particles, cells, and viruses. In some examples, the exhaust filter may have a rejection accuracy of up to 0.02 micrometers. In some examples, the filtered gas may be discharged into ambient air, for example, from the patient and surgical team.

[0552] An additional discharge conduit 2630 may be configured to receive a filtered stream of blown gas from the discharge filter 2628. The additional discharge conduit 2630 may be configured to deliver the blown gas stream from the patient. The additional discharge conduit 2630 may be configured to connect to a vacuum source 2632.

[0553] One or more of the discharge conduit 2626 or the other discharge conduit 2630 may otherwise be substantially similar to (e.g., structurally or functionally similar to) the expiratory conduit 146 of the respiratory support system 100. Specifically, one or more of the discharge conduit 2626 or the other discharge conduit 2630 may be at least partially formed of a breathable material and may include one or more of the following: reinforcing member 502, multiple retainers 1308, corrugated profile, membrane 2002, or composite material, as described above.

[0554] Because the patient's body cavities may already be moist, the inhaled airflow will hardly (if) lose moisture while inside the patient's body. If the inhaled airflow is not saturated before entering the patient's body, it may become completely saturated.

[0555] In use, as the inhaled gas flows out of the patient's body cavity, it may flow along the discharge conduit 2626. The discharge conduit 2626 may be exposed to ambient air. The walls of the discharge conduit 2626 may be colder than the inhaled gas flow. Condensation may form within the lumen of the discharge conduit 2626. Alternatively or additionally, condensation may form within one or more other components of the surgical airflow system 2600, such as the discharge filter 2628 or an additional discharge conduit 2630.

[0556] Condensation in the exhaust filter 2628 can saturate it. The exhaust filter 2628 may become at least partially clogged. Clogged exhaust filter 2628 may cause increased back pressure. Clogged exhaust filter 2628 may hinder the dissipation of surgical smoke within the patient's body cavity. Surgical smoke trapped in the patient's body cavity or exhaust duct 2626 may be harmful to the patient. The surgeon's field of vision may be obstructed or impaired by trapped surgical smoke. Filter blockage may allow contaminants to escape into the operating room.

[0557] The discharge conduit 2626 or additional discharge conduit 2630, which is at least partially formed of breathable material, can advantageously reduce the formation of condensate and / or dissipate other liquids within the surgical blow-in system 2600.

[0558] In other examples, the surgical air intake system 2600 may include a recirculation system, such as replacing the smoke exhaust system 2624.

[0559] The recirculation system can be configured to return the exhausted blown-in gas stream to the patient's body cavity. The recirculation system may include one or more of a discharge catheter, a discharge filter, or other discharge catheters. Additional discharge catheters may be coupled to additional surgical cannulas. The discharge catheter, discharge filter, or other discharge catheter may otherwise resemble the discharge catheter 2626, discharge filter 2628, or other discharge catheter 2630 of the smoke extraction system 2624, as described above.

[0560] Surgical blow-in circuit

[0561] In the illustrated example, a surgical air intake system 2600, a humidifier supply conduit 2612, a humidification chamber, a delivery conduit 2616, an exhaust conduit 2626, an exhaust filter 2628, and an additional exhaust conduit 2630 may form a surgical air intake circuit. More specifically, this particular configuration may form a dual-limb surgical air intake circuit 2634. The humidifier supply conduit 2612, the humidification chamber, and the delivery conduit 2616 may be considered as inlet branches forming the dual-limb surgical air intake circuit 2634. The exhaust system 2624 (e.g., exhaust conduit 2626, exhaust filter 2628, and additional exhaust conduit 2630) may be considered as an outlet branch forming the dual-limb surgical air intake circuit 2634.

[0562] One or more components of the surgical airflow circuit 2634 and / or the surgical airflow system 2600 may be packaged together and / or sold as a surgical airflow circuit kit.

[0563] While various examples have been described in detail above, it should be understood that one or more features or variations of one example can be combined with features or variations of one or more other examples. However, this is not limited to: Figure 5 or Figure 6 The internal reinforcing member 502 may be combined with any one or more of the following: o Figures 8 to 11 External reinforcing member 502 of any of them; o Figures 13 to 16 Holder 1308 of any of them; o Figure 17 or Figure 18 The wavy outline; o Figure 20 or Figure 21 The membrane 2002; or o Figures 22 to 25 306 composite material slender tube; Figures 8 to 11 The external reinforcement member 502 of any of the following may be combined with any one or more of the following: o Figure 5 or Figure 6 Internal reinforcing component 502; o Figures 13 to 16 Holder 1308 of any of them; o Figure 17 or Figure 18 The wavy outline; o Figure 20 or Figure 21 The membrane 2002; or o Figures 22 to 25 306, a composite material slender tube of any one of them; Figures 13 to 16 The retainer 1308 of any of the following can be combined with any one or more of the following: o Figure 5 or Figure 6 Internal reinforcing component 502; o Figures 8 to 11 External reinforcing member 502 of any of them; o Figure 17 or Figure 18 The wavy outline; o Figure 20 or Figure 21 The membrane 2002; or o Figures 22 to 25 306, a composite material slender tube of any one of them; Figure 17 or Figure 18 The wavy profile can be combined with any one or more of the following: o Figure 5 or Figure 6 The internal reinforcing member 502 may be combined with any one or more of the following: o Figures 8 to 11 External reinforcing member 502 of any of them; o Figures 13 to 16 Holder 1308 of any of them; o Figure 20 or Figure 21 The membrane 2002; or o Figures 22 to 25 306, a composite material slender tube of any one of them; Figure 20 or Figure 21 The membrane 2002 can be combined with any one or more of the following: o Figure 5 or Figure 6 The internal reinforcing member 502 may be combined with any one or more of the following: o Figures 8 to 11 External reinforcing member 502 of any of them; o Figures 13 to 16 Holder 1308 of any of them; o Figure 17 or Figure 18 The wavy outline; o Figures 22 to 25 The composite material slender tube 306 of any of the above; and Figures 22 to 25 The composite material slender tube 306 of any of the following can be combined with any one or more of the following: o Figure 5 or Figure 6 The internal reinforcing member 502 may be combined with any one or more of the following: o Figures 8 to 11 External reinforcing member 502 of any of them; o Figures 13 to 16 Holder 1308 of any of them; o Figure 17 or Figure 18 The wavy outline; o Figure 20 or Figure 21 The film 2002.

[0564] Unless the context explicitly requires otherwise, throughout the specification and claims, the words “comprising,” “including,” and variations thereof shall be interpreted in an inclusive sense, meaning “including but not limited to,” rather than an exclusive sense.

[0565] Any reference to a publication or product throughout this specification, including the background section, should not be construed as an admission that the publication or product is necessarily prior art, similar art, well-known art, or constitutes part of common general knowledge in the art.

[0566] Glossary

[0567] "Permeable material" refers to a non-porous permeable material that allows water molecules to pass through the monolithic wall of the permeable material via a dissolution-diffusion mechanism, but does not allow liquid water or a stream of breathing gases to pass through the wall as a whole. Those skilled in the art will understand that the water molecules in the wall are dispersed molecularly in the medium and therefore do not have a state (solid, liquid, or gaseous), although they are sometimes referred to in the art as vapor (e.g., the transport rate is often referred to as water vapor transmission rate (MVTR), etc.). It should be further understood that the monolithic wall does not contain open channels or pores from one main surface to another, allowing pathogens to pass through such channels along with air or liquid water droplets via pore flow mechanisms. However, this definition is not intended to exclude tubes or membranes formed from such permeable materials, which may have one or more pores provided by the material (such as those possibly caused by manufacturing defects), which may produce negligible pore flow that does not materially affect the overall performance of the conduit or compliance with the leakage requirements of ISO 5367:2014. It should also be understood that, as with all polymers, the transport of some small molecules in respiratory gases (such as oxygen, carbon dioxide, nitrogen, or helium) may occur in minute or very small amounts (i.e., not a “bulk” flow), typically at rates at least an order of magnitude lower than that of water molecules for breathable materials as defined herein. Furthermore, particularly relevant to respiratory gases delivered to or from patients, the amount of such small molecule transport may be less than that permitted by compliance requirements in relevant standards, such as the permissible amounts in the leak test (conducted in Section 5.4 by the method specified in Annex E) of ISO 5367:2014 (which is incorporated herein by reference in its entirety).

[0568] "Compliance" is defined in section 3.1.5 of ISO standard 4135:2001 (the entire text of which is incorporated herein by reference) as "the volume added per unit increase in pressure when gas is added to a closed space, expressed in terms of the temperature and humidity of the closed space at ambient atmospheric pressure" (© ISO 2001). The method for testing the compliance of a conduit according to this disclosure is based on the method described in Annex H of ISO 5367:2014 (the entire text of which is incorporated herein by reference). First, seal any leaks in the conduit equal to or greater than 1 ml / min (as described in Annex E). Second, condition the conduit to 42 ± 3°C and a relative humidity of not less than 80% for at least one hour. Third, seal one end of the conduit and place the conduit on a flat surface. Fourth, connect a pressure measuring device to the opposite end of the conduit. Fifth, inflate the conduit to a stable gauge pressure of 60 ± 3 cmH2O within five seconds or less and record the required air volume. It should be understood that the conditioning defined by this standard may not be reflected in the conditions of use, and the standard did not take breathable materials into account when it was drafted. To better reflect the conditions of use, the compliance of conduits formed at least in part by breathable materials can be further tested by additionally or alternatively conditioning the conduits to simulated conditioning states as described below.

[0569] "Regulated state" refers to one of a series of continuous states in which a catheter or tube has been exposed to a water vapor pressure gradient for an extended period, resulting in a relatively high partial pressure of water vapor within the lumen (i.e., higher than the partial pressure of water vapor in ambient air). In other words, the tube wall has absorbed water molecules from the lumen and may continue to do so. Specifically, a catheter that has been and continues to be used to deliver a humidified respiratory gas flow for a period of time can be considered to be in a regulated state. The concentration of water molecules contained in the tube wall in a regulated state is generally higher than that contained in a dry or equilibrium state, but generally lower than that contained in a saturated state. References in this document to certain characteristics of a catheter in "one" (singular) regulated state are not necessarily intended to apply to all cases. allConditioning states, unless otherwise apparent from the context. Specifically, depending on design requirements and the configuration of conduit parameters, the relative humidity and temperature of the breathing gas and ambient air, and the concentration of water molecules within the conduit's permeable material, conduit expansion may or may not be suppressed. That is, within a series of continuous conditioning states, there may be subsets of unconstrained and constrained conditioning states. Conditioning states can be simulated by conditioning the conduit as follows: First, an ambient temperature of 22 ± 2°C should be reached and maintained throughout the conditioning process. Second, the conduit is laid in a V-shaped tray in a balanced state. Third, gas is supplied to the conduit's lumen at a flow rate of 10 standard liters per minute (SLPM) (reference 20°C, 101.325 kPa), humidified for 24 hours at 100% relative humidity (RH) by a humidifier with a humidity level set to a 37°C dew point.

[0570] "Dry condition" refers to the state of a catheter, tube, or sample thereof, in which it has been dried according to the drying method of ISO 62:2008(E), as briefly described with respect to the second step of the immersion test method defined below. This is an "artificial" state because the tube would not normally enter this state during normal use (e.g., for use in assisted breathing systems). The concentration of water molecules contained in the tube wall in the dry condition is typically lower than the concentration of water molecules contained in any of the equilibrium, conditioned, and saturated states.

[0571] "Equilibrium state" refers to a state in which a conduit or tube, typically free of condensation or other liquids, has been exposed to ambient air (e.g., in a controlled environment with a relative humidity of 40% to 60% inside the cavity and outside the tube wall) for a sufficient period to reach a steady state. In other words, the water molecule concentration within the breathable material is in equilibrium with the ambient air. The water molecule concentration contained within the tube wall in the equilibrium state is typically higher than that in the dry state, but generally lower than that in the conditioned or saturated state. Depending on the conduit configuration, environmental conditions (including ambient air temperature and relative humidity), and the water molecule concentration within the breathable material of the tube, tube expansion may or may not be suppressed. However, in at least some examples, the conduit may be designed to allow the tube to expand at least partially from the equilibrium state before further expansion is suppressed.

[0572] The "immersion test" refers to the test used to determine water absorption based on ISO 62:2008(E) standard (© ISO, 2008) (the entire text of which is incorporated herein by reference). First, cut at least three tubular test specimens, each 25 ± 1 mm in length, from the tube. The cut should be perpendicular to the longitudinal direction of the tube. The cut edges should be smooth and free of cracks. If possible, the specimen should consist only of the active plastic responsible for the water absorption properties. If possible, the heater wires, sleeves, and any mechanical support materials should be removed non-destructively. Second, dry the specimen. The specimen can be dried in a convection oven or vacuum oven maintained at 50 ± 2°C for at least 24 hours, or at a temperature of 60°C, a dew point of -40°C, and an air flow rate of 14 m³ / h (m³ / h). 3 The specimens were dried in an industrial dryer under conditions of 600 minutes (min) and 6 hours (h). The specimens should be weighed periodically (accurate to 1 mg) and returned to the oven / dryer until their mass is consistently within ±1 mg. Third, the specimens were cooled to room temperature in a desiccator. Fourth, the specimens were weighed (m1) and their dimensions measured. Fifth, the specimens were immersed in distilled water for 24 hours. At least 8 ml of distilled water should be used per square centimeter of total surface area of ​​the specimen, with a minimum of 300 ml per specimen. If necessary, the specimens could be placed in a stainless steel wire basket anchored to a weight using stainless steel wire. Sixth, the specimens were removed from the water and the surface moisture was removed using a lint-free cloth. Seventh, the specimens were weighed within 1 minute of being removed from the water (accurate to 1 mg). Eighth, steps six (immersion) and seven (weighing) were repeated until the mass of the specimens was consistently within ±1 mg (m2). Ninth, if the specimen is known or suspected to contain a significant amount of water-soluble components, repeat step two (drying) and weigh the sample to correct for water-soluble substances lost during the immersion test. If the readjusted mass is less than the adjusted mass, the difference represents the water-soluble substances lost during the immersion test. The absorbency of each specimen is determined according to the equation... or (For specimens containing water-soluble substances) expressed as mass c Percentage change relative to the initial mass. The result is expressed as the arithmetic mean of three (or more) values ​​obtained over the same exposure duration. References to immersion tests in this specification refer to tests performed on individual specimens of the breathable material or tubing, isolated from connectors or reinforcements so that expansion is not inhibited.

[0573] "ISO" refers to the International Organization for Standardization, and more specifically, to the international standards defined by that organization. These standards are protected by copyright and can be purchased directly from the International Organization for Standardization at http: / / www.ISO.org.

[0574] "Leakage" and "leakage test" refer to the methods set forth in Section 5.4 and Annex E of ISO 5367:2014 (© ISO 2014) (the entire text of which is incorporated herein by reference). This standard specifies limits for complete breathing apparatus or supplied catheters ready for use with a ventilator-controlled breathing system (VBS) or anesthesia-controlled breathing system: at a pressure of 60 ± 3 cmH2O, the limit is 70 ml / min for adult patients (intended delivery volume ≥ 300 ml), 40 ml / min for pediatric patients (< 300 ml), and 30 ml / min for neonatal patients (≤ 50 ml). For single catheters not intended for use with a VBS or anesthesia-controlled breathing system, the leakage limit at 60 ± 3 cmH2O is 25 ml / min. In short, when testing for leakage according to the standard, first, the catheter is conditioned at a temperature of 23 ± 3°C for at least one hour. Second, one end of the catheter is sealed. Third, an internal gas pressure of 60 ± 3 cmH2O is applied and maintained. Fourth, record the airflow required to maintain this pressure. It should be understood that the conditioning defined by this standard may not be reflected in the operating conditions, and the standard was not drafted with breathable materials in mind. To better reflect operating conditions, leakage in ducts formed at least partially by the breathable material can be further tested by additionally or alternatively conditioning the ducts to simulated conditioning conditions as described above.

[0575] "Prolonged use," "long-term use," and "long-term" refer to the use of catheters in medical gas systems (e.g., respiratory support systems) to continuously deliver heated and humidified medical gases for at least 24 hours. Long-term use can be simulated through the simulated conditioning conditions described above.

[0576] "Flow resistance" and "flow resistance test" refer to the methods described in Section 5.5 and Annex F of ISO 5367:2014 (© ISO 2014) (the entire contents of which are incorporated herein by reference in their entirety). This standard specifies the flow resistance limits for supplied, ready-to-use catheters: 30 L / min for adult patients (expected delivery volume ≥300 ml) at 0.06 cmH2O / L / min; 15 L / min for pediatric patients (<300 ml) at 0.12 cmH2O / L / min; and 2.5 L / min at 0.74 cmH2O / L / min. In short, the flow resistance is tested by first conditioning the catheter at 23 ± 3°C for at least one hour. Second, the flow rate of the flow control device is adjusted and maintained for 30 seconds, and the pressure is recorded. Third, the catheter is fitted above the outlet of the buffer reservoir, and the free end of the catheter is secured so that the catheter remains straight. Fourth, readjust the airflow and maintain it for 30 seconds, recording the pressure. Fifth, calculate the pressure increase caused by the conduit based on the difference in recorded pressure. First, test the increase in flow resistance when bending by conditioning the conduit for at least one hour at a temperature of 42±3°C and at least 80% relative humidity. Second, suspend the conduit above a cylinder with a diameter of 25 mm and apply tension to maintain contact with half the circumference of the cylinder. Third, apply the airflow and record the pressure after five minutes. Fourth, calculate the pressure increase caused by the conduit based on the pressure difference between the bent and straight conduits. It should be understood that the conditioning defined by this standard may not reflect the conditions of use, and the standard did not take into account breathable materials at the time of drafting. To better reflect the conditions of use, the flow resistance of conduits, which are at least partially formed by breathable materials, can be further tested by additionally or alternatively conditioning the conduit to the simulated conditioning state described above.

[0577] "Saturation state" refers to the state of a catheter or tube, or a sample thereof, after it has undergone an immersion test (i.e., soaking in liquid water) for a period of time until the breathable material no longer absorbs or absorbs negligible amounts of more water molecules; that is, until the total mass of the breathable material and the absorbed water molecules reaches or approaches its maximum. This is an "artificial" state because the catheter or tube typically does not enter this state during normal use (i.e., for use in respiratory support systems). The concentration of water molecules contained in the tube wall in the saturated state is generally higher than the concentration of water molecules contained in any of the dry, equilibrium, or conditioned states.

[0578] List of elements in the attached image

[0579] 100 Respiratory Assist System

[0580] 102 Humidifier

[0581] 104 gas source

[0582] 106 pressure generator

[0583] 108 Ambient Air

[0584] 110 Ambient Air Inlet

[0585] 112 Gas Source Controller

[0586] 114 User Interface

[0587] 116 Humidifier Supply Pipe

[0588] 118 Gas Source Outlet

[0589] 120 Humidification Room

[0590] Entrance to Room 122

[0591] Exit of Room 124

[0592] 126-chamber heater

[0593] 128 Humidifier Controller

[0594] 130 Inspiratory Tube

[0595] 132 User Interface

[0596] 134 communication link

[0597] 136 heater wire

[0598] 138 sensor probe

[0599] 140 sensor lead

[0600] 142 Y-shaped parts

[0601] 144 Patient Interface

[0602] 146 expiratory catheter

[0603] 148 Gas Reflux Inlet

[0604] 150 breathing circuit

[0605] 152 Intake Branch

[0606] 154 expiratory branches

[0607] 202 Heater Base

[0608] 204 housing

[0609] 206 boxes

[0610] 208 buttons

[0611] 210 monitor

[0612] 212 indicator lights

[0613] 214 connector

[0614] 216 connector

[0615] 218 Release Button

[0616] 302 connector

[0617] 304 connector

[0618] 306 slender tube

[0619] 402 Entrance Area

[0620] 404 Export Area

[0621] 406 Middle Area

[0622] 408 protrusion

[0623] 502 reinforced component

[0624] 504 arrow

[0625] 702 Longitudinal Section

[0626] 704 radial portion

[0627] 902 Ring Component

[0628] 904 Longitudinal Components

[0629] 906 opening

[0630] 1202 braided sheath

[0631] 1204 orifice

[0632] 1302 connector

[0633] 1304 connector

[0634] 1306 slender tube

[0635] 1308 retainer

[0636] 1402 clip

[0637] 1404 opening

[0638] 1502 ball connector

[0639] 1504 socket

[0640] 1602 arms

[0641] 1702 outer peak

[0642] 1704 First radius of curvature

[0643] 1706 Outer Valley

[0644] 1708 Second radius of curvature

[0645] 1710 inner peak

[0646] 1712 Third radius of curvature

[0647] 1714Nepo Valley

[0648] 1716 Fourth radius of curvature

[0649] 1718 sidewall

[0650] 2002 membrane

[0651] 2004 air gap

[0652] 2102 perforation

[0653] 2104 slender tube

[0654] 2106 air gap

[0655] 2600 Surgical Inhalation System

[0656] 2602 gas source

[0657] 2604 Wall Source

[0658] 2606 compressed gas cylinder

[0659] 2608 blow-in device supply conduit

[0660] 2610 blow-in device

[0661] 2612 Humidifier Supply Pipe

[0662] 2614 Humidifier

[0663] 2616 delivery catheter

[0664] 2618 Surgical Cannula

[0665] 2620 endoscope

[0666] 2622 Laparoscopic Monitor

[0667] 2624 smoke exhaust system

[0668] 2626 discharge duct

[0669] 2628 emission filter

[0670] 2630 Additional discharge duct

[0671] 2632 vacuum source

[0672] 2634 Surgical blow-in circuit

Claims

1. A medical gas loop assembly for delivering a flow of medical gas in a medical gas system, the medical gas system comprising: Inlet catheter; An outlet conduit configured to be fluidly coupled to the inlet conduit, at least a portion of the outlet conduit being configured to expand more than the inlet conduit in at least a longitudinal direction during use; and A plurality of retainers, each of which is configured to retain a portion of the inlet conduit and a portion of the outlet conduit to tether the outlet conduit to the inlet conduit, the plurality of retainers being configured in conjunction with the inlet conduit to suppress, in use, expansion of at least a portion of the outlet conduit along the longitudinal direction.

2. A medical gas loop assembly for delivering a flow of medical gas in a medical gas system, the medical gas system comprising: Inlet catheter; An outlet conduit, the outlet conduit comprising a breathable material; and A plurality of retainers, each of the plurality of retainers including a pair of retaining members, one of the retaining members being configured to receive and retain a portion of the inlet conduit, and the other retaining member being configured to receive and retain a portion of the outlet conduit, for tethering the outlet conduit to the inlet conduit.

3. The medical gas circuit kit according to claim 1 or 2, wherein the plurality of retainers comprises: At least two retainers; At least 3 retainers; 2 to 120 retainers; 3 to 60 retainers; 4 to 40 retainers; or The outlet conduit has a retainer for every 4 to 50 corrugations.

4. The medical gas circuit kit according to any one of claims 1 to 3, wherein the plurality of retainers are configured as follows: Engagement with the inlet conduit at multiple discrete locations along its length; and / or It engages with the outlet conduit at multiple discrete locations along the length of the outlet conduit.

5. The medical gas circuit kit according to any one of claims 1 to 4, wherein at least one of the plurality of retainers is configured to suppress radial expansion of the outlet conduit by surrounding at least a majority of its circumference during use.

6. The medical gas circuit kit according to any one of claims 1 to 5, wherein, in use, the absorption of water molecules by the outlet conduit causes the outlet conduit to expand radially between consecutive pairs of retainers in the plurality of retainers.

7. The medical gas circuit kit according to any one of claims 1 to 6, wherein each of the plurality of retainers is configured to retain corresponding portions of the inlet catheter and the outlet catheter in a side-by-side relationship.

8. The medical gas circuit kit of claim 7, wherein each of the plurality of retainers is configured to keep corresponding portions of the inlet conduit and the outlet conduit substantially adjacent to each other, such that the outlet conduit is at least partially heated by the inlet conduit during use.

9. The medical gas circuit kit according to any one of claims 1 to 8, wherein each of the plurality of retainers is configured to engage with one or more of the following: The inlet conduit is configured to inhibit movement along its length; and / or The outlet conduit is designed to suppress movement along its length.

10. The medical gas circuit kit according to any one of claims 1 to 9, The inlet conduit includes a plurality of corrugations, each of the plurality of retainers being configured to engage with one or more of the plurality of corrugations of the inlet conduit; and / or The outlet conduit includes a plurality of corrugations, each of the plurality of retainers being configured to engage with one or more of the plurality of corrugations of the outlet conduit.

11. The medical gas circuit kit according to any one of claims 1 to 10, wherein each of the plurality of retainers comprises: A first clamp, configured to be detachably fitted around said portion of the inlet conduit; and A second clamp is configured to be detachably fitted around the portion of the outlet conduit.

12. The medical gas circuit kit according to claim 11, wherein: The first clamp is partially annular and defines an opening through which the inlet conduit is removably received; And / or The second clamp is partially annular and defines an opening through which the outlet conduit is detachably received.

13. The medical gas circuit kit according to any one of claims 1 to 12, wherein one or more of the plurality of retainers are configured to be mechanically connected to one or more other retainers of the plurality of retainers.

14. The medical gas circuit kit of claim 13, wherein the mechanical connection comprises one or more of the following: Clip-on connection; Pivotable connection; or Ball-and-socket connection.

15. The medical gas circuit kit according to any one of claims 1 to 14, each of the plurality of retainers comprising: First connector; and The second connector is configured to establish a mechanical connection with the first connector of another of the plurality of retainers.

16. The medical gas circuit kit of claim 15, wherein each of the plurality of retainers includes an arm, and: The distal end of the arm includes the first connector; and / or The proximal end of the arm includes the second connector.

17. The medical gas circuit kit according to claim 15 or 16, wherein the first connector comprises a ball connector, and the second connector comprises a socket. The ball connector is configured to establish a ball-and-socket connection with the socket of another retainer among the plurality of retainers, and / or The socket is configured to establish a ball-and-socket connection with the ball connector of another of the plurality of retainers.

18. The medical gas circuit kit according to any one of claims 1 to 17, wherein each of the plurality of retainers is substantially identical.

19. The medical gas circuit kit according to any one of claims 1 to 18, wherein each of the plurality of retainers is integrally formed, for example, from a polymer material.

20. The medical gas circuit kit according to any one of claims 1 to 19, wherein the inlet conduit includes a heater (e.g., a heating wire).

21. The medical gas circuit kit according to any one of claims 1 to 20, wherein each of the plurality of retainers is configured as follows: When the outlet conduit is in one or more of the regulating or saturated states, the radial expansion of the portion of the outlet conduit is suppressed; and / or When the outlet conduit is in one or more of a dry or balanced state, the radial expansion of the portion of the outlet conduit is not inhibited.

22. The medical gas circuit kit according to any one of claims 1 to 21, wherein the length of the outlet catheter in equilibrium is between about 0.8 m and 2.5 m, and optionally: Between approximately 0.8m and 1.4m, or between approximately 1.0m and 1.4m, for example, approximately 1.2m; or Between approximately 1.2m and 2.0m, or between approximately 1.4m and 1.8m, for example, approximately 1.6m.

23. The medical gas circuit kit according to any one of claims 1 to 22, wherein the medical gas circuit kit does not include at least one of the following, and optionally does not include two of the following: A heater (e.g., a heating wire or a water jacket), the heater being configured for use with the outlet conduit; or A water collector configured for use with the outlet conduit.

24. The medical gas circuit kit according to any one of claims 1 to 23, wherein the outlet conduit comprises an elongated tube, the elongated tube comprising a breathable material, which, in use, expands in one or more of the radial or longitudinal directions due to the absorption of water molecules.

25. The medical gas circuit kit of claim 24, wherein the breathable material comprises a block polymer, the block polymer optionally comprising one or more of the following: Polybutylene terephthalate hard segments; or Polyether-type macromolecular diol soft segments.

26. The medical gas circuit kit according to any one of claims 1 to 25, wherein the outlet conduit comprises an elongated tube configured to absorb at least 33%, about 33% to 200%, about 100% to 160%, about 120% to 140%, or about 130% to 135% (e.g., 133%) of its own mass of water molecules in an immersion test.

27. The medical gas circuit kit according to any one of claims 1 to 26, wherein the outlet conduit comprises an elongated tube configured to expand at least one of the radial direction or the longitudinal direction during an immersion test, and optionally in each direction by at least 20%, about 20% to 70%, about 25% to 50%, or about 30% to 50%.

28. The medical gas circuit kit according to any one of claims 1 to 27, wherein the medical gas circuit kit includes a breathing circuit kit, the medical gas system includes a breathing assist system, the inlet catheter includes an inspiratory catheter, and the outlet catheter includes an expiratory catheter.

29. The medical gas circuit kit according to any one of claims 1 to 28, wherein the medical gas circuit kit further comprises any one or more of the following: Humidifier supply pipe; Pressure reducing valve; Humidification room; Y-shaped parts; Insertion connector; Patient interface; catheter hanger; Filter; or Pressure regulator.

30. The medical gas circuit kit according to any one of claims 1 to 27, wherein the medical gas circuit kit includes an anesthesia breathing circuit kit, the medical gas system includes an anesthesia breathing system, the inlet catheter includes an inspiratory catheter, and the outlet catheter includes an expiratory catheter.

31. The medical gas circuit kit according to any one of claims 1 to 27, the medical gas circuit kit comprising a surgical inhalation circuit kit, the medical gas system comprising a surgical inhalation system, the inlet catheter comprising a delivery catheter, and the outlet catheter comprising a discharge catheter.

32. A medical gas conduit for delivering a flow of medical gas in a medical gas system, the medical gas conduit comprising: A slender tube defining an inner cavity through which the medical gas flows, at least a portion of the slender tube comprising a breathable material that, in use, is configured to expand due to the absorption of water molecules. A pair of connectors, disposed at respective ends of the elongated tube, the pair of connectors being configured to pneumatically couple the medical gas conduit to other components of the medical gas system; and A reinforcing member, configured to engage with the elongated tube at least along its length at a plurality of discrete locations between the pair of connectors, the reinforcing member being configured to: Prevent at least a portion of the elongated tube from expanding in one or more of the radial or longitudinal directions; and / or Improve one or more of the crush resistance or crush recovery of at least a portion of the medical gas conduit.

33. The medical gas conduit of claim 32, wherein the reinforcing member is fixedly attached to the pair of connectors.

34. The medical gas conduit according to claim 32 or 33, wherein the reinforcing member is at least partially located within the lumen of the elongated tube.

35. The medical gas conduit according to any one of claims 32 to 34, wherein the reinforcing member comprises a helical shape.

36. The medical gas conduit according to any one of claims 32 to 35, wherein the reinforcing member is fixedly attached to the elongated tube at one or more locations along the length of the elongated tube between the pair of connectors.

37. The medical gas conduit according to any one of claims 32 to 36, wherein the reinforcing member is fixedly attached to one or more of the pair of connectors or to the corresponding end of the elongated tube.

38. The medical gas conduit according to any one of claims 32 to 37, wherein the reinforcing member is configured as follows: The elongated tube is biased to a predetermined length, which is optionally approximately equal to the length of the elongated tube in its equilibrium state; and / or When in use, the slender tube is in a tensioned state when it is in the adjustment state.

39. The medical gas conduit according to any one of claims 32 to 38, wherein the reinforcing member is formed at least in part by one or more of the following: Plastic alloy materials; and / or Polymer materials, such as polypropylene.

40. The medical gas conduit according to any one of claims 32 to 39, wherein the reinforcing member is configured to wick condensate or other liquid within the inner lumen during use.

41. The medical gas conduit according to any one of claims 32 to 40, wherein the reinforcing member comprises one or more grooves configured to at least partially wick the condensate or the other liquid by capillary action.

42. The medical gas conduit according to any one of claims 32 to 41, wherein the reinforcing member comprises a longitudinal portion and a plurality of radial portions, each of the plurality of radial portions extending outward from the longitudinal portion and configured to engage a corresponding portion of the elongated tube or the pair of connectors.

43. The medical gas conduit according to claim 42, wherein the longitudinal portion is disposed at the center of the inner lumen or around the center of the inner lumen.

44. The medical gas conduit of claim 42 or 43, wherein the elongated tube is corrugated, and one or more of the plurality of radial portions are configured to engage with the corresponding corrugations of the elongated tube, for example, by friction fit or interference fit.

45. The medical gas conduit according to any one of claims 32 to 44, wherein the reinforcing member is at least partially located outside the elongated tube, for example, substantially concentric around the elongated tube.

46. ​​The medical gas conduit according to claim 45, wherein the reinforcing member comprises a double helix structure.

47. The medical gas conduit according to claim 45 or 46, wherein the reinforcing member comprises a hollow structure.

48. The medical gas conduit of claim 47, wherein the hollow structure is at least partially formed of an elastomeric material.

49. The medical gas conduit according to claim 47 or 48, wherein the hollow structure comprises: A plurality of annular members, the plurality of annular members being arranged substantially coaxially and spaced apart along at least a portion of the length of the elongated tube; and Multiple longitudinal members, each extending between corresponding consecutive pairs of the multiple annular members.

50. The medical gas conduit of claim 49, wherein the elongated tube is corrugated, and one or more of the plurality of annular members are configured to engage with the corresponding corrugation of the elongated tube when the medical gas conduit is in one or more of a balanced or regulated state.

51. The medical gas conduit of claim 49 or 50, wherein the plurality of longitudinal members are rotatably biased between two or more consecutive pairs of the plurality of annular members.

52. The medical gas conduit according to any one of claims 49 to 51, wherein the hollow structure is formed at least in part by one or more of the following: Polymer materials, such as polypropylene; and / or Plastic alloy.

53. The medical gas conduit of claim 45, wherein the reinforcing member is at least partially formed of a shape memory material.

54. The medical gas conduit of claim 53, wherein the reinforcing member is configured to deform in response to temperature changes in the elongated tube during use.

55. The medical gas conduit of claim 45, wherein the reinforcing member is malleable.

56. The medical gas conduit of claim 45, wherein the reinforcing member includes a sheath, wherein the sheath is not a braided sheath.

57. The medical gas conduit of claim 56, wherein the sheath is configured to at least partially conform to the outer surface of the elongated tube when the medical gas conduit is in a balanced state.

58. The medical gas conduit of claim 56 or 57, wherein the elongated tube is corrugated, and the sheath is configured to conform to the outer crest of the outer surface of the elongated tube when the medical gas conduit is in equilibrium.

59. The medical gas conduit according to claim 32, wherein the reinforcing member is embedded within the elongated tube.

60. A medical gas conduit for delivering a flow of medical gas in a medical gas system, the medical gas conduit comprising: A membrane comprising a breathable material, wherein, in use, the breathable material is configured to expand due to the absorption of water molecules; and Slender tube, the slender tube: Arranged substantially concentrically with respect to the membrane; The membrane is fixedly attached at multiple discrete locations along the length of the elongated tube; Configured to support the membrane; It is configured to be able to penetrate water molecules; and It is configured to suppress at least a portion of the membrane from expanding in either the radial or longitudinal direction during use.

61. The medical gas conduit of claim 60, wherein the membrane at least partially defines an inner lumen for the flow of the medical gas.

62. The medical gas conduit of claim 60 or 61, wherein the elongated tube is directly attached to the membrane at a plurality of discrete locations along the length of the elongated tube.

63. The medical gas conduit according to any one of claims 60 to 62, wherein the medical gas conduit does not include ribs (e.g., spiral ribs) located between the membrane and the elongated tube.

64. The medical gas conduit according to any one of claims 60 to 63, wherein the elongated tube comprises a corrugated elongated tube.

65. The medical gas conduit of claim 64, wherein the membrane is directly attached to the outer crest of the corrugated elongated tube or the inner crest of the corrugated elongated tube, and spans between the outer crest or the inner crest.

66. The medical gas conduit according to any one of claims 60 to 65, wherein the membrane has a wall thickness of less than about 200 micrometers (μm), less than about 100 μm, less than about 80 μm, less than about 60 μm, less than about 40 μm, or about 20 μm.

67. The medical gas conduit according to any one of claims 60 to 66, wherein the elongated tube is arranged substantially concentrically around the membrane.

68. The medical gas conduit according to any one of claims 60 to 67, wherein the membrane is configured to extend between adjacent inner wave peaks on the inner surface of the elongated tube.

69. The medical gas conduit of claim 67, wherein the membrane forms a substantially smooth inner pore of the medical gas conduit.

70. The medical gas conduit according to any one of claims 60 to 66, wherein the membrane is arranged concentrically around the elongated tube.

71. The medical gas conduit according to any one of claims 60 to 66 or 70, wherein the membrane is configured to extend between adjacent outer peaks on the outer surface of the conduit.

72. The medical gas conduit according to any one of claims 60 to 66 or 70 to 71, wherein the elongated tube is porous (e.g., perforated).

73. The medical gas conduit according to any one of claims 60 to 72, wherein the membrane and the elongated tube comprise a co-extruded member.

74. The medical gas conduit according to any one of claims 60 to 73, wherein the membrane and the elongated tube comprise different materials.

75. A medical gas conduit for delivering a flow of medical gas in a medical gas system, the medical gas conduit comprising an elongated tube, the elongated tube being at least partially formed of a composite material, the composite material comprising: Polymer matrix; and Reinforcing materials.

76. The medical gas conduit according to claim 75, wherein the polymer matrix comprises a breathable material.

77. The medical gas conduit according to claim 75 or 76, The composite material comprises a fiber-reinforced polymer; and / or The reinforcing material includes fiber reinforcement.

78. The medical gas conduit according to claim 77, wherein the fiber reinforcement comprises one or more of the following: Synthetic fibers, such as one or more of carbon fiber, glass fiber, or aramid fiber; or Natural fibers, such as one or more of cellulose fibers, jute fibers, flax fibers, or hemp fibers.

79. The medical gas conduit according to claim 77 or 78, wherein, in one or more of a dry or equilibrium state, the volume fraction of the fiber reinforcement accounts for about 5% to 60%, about 10% to 50%, about 20% to 40%, or about 30% of the elongated tube.

80. The medical gas conduit according to any one of claims 77 to 79, wherein the average diameter of the fiber reinforcement is between about 3 µm and 20 µm.

81. The medical gas conduit according to any one of claims 77 to 80, wherein the fibers of the fiber reinforcement comprise a fiber sizing agent.

82. The medical gas conduit according to any one of claims 75 to 81, wherein the reinforcing material comprises discontinuous fibers.

83. The medical gas conduit according to claim 82, wherein the discontinuous fibers conform to one or more of the following: The average length is less than about 25 millimeters (mm), or less than about 5 millimeters; The average length is at least 0.5 mm, between about 0.5 mm and 10 mm, or between about 1 mm and 5 mm, for example, about 1.5 mm or about 3 mm; The average diameter is between approximately 5 μm and 30 μm, or between approximately 10 μm and 20 μm, for example, approximately 15 μm; or The aspect ratio is higher than the critical fiber length of the polymer matrix.

84. The medical gas conduit according to claim 82 or 83, wherein: The discontinuous fibers are arranged randomly. The discontinuous fibers are arranged in the circumferential direction; The discontinuous fibers are arranged in the longitudinal direction; or About 20% to 100% or at most about 80% of the discontinuous fibers are arranged in the same direction as each other (e.g., along either the circumferential direction or the longitudinal direction).

85. The medical gas conduit according to any one of claims 75 to 84, wherein the reinforcing material comprises continuous fibers, the continuous fibers optionally spanning one or more of the length or circumference of the elongated tube.

86. The medical gas conduit of claim 85, wherein the continuous fiber comprises a fabric, for example, a woven, knitted, felted, or braided preform.

87. The medical gas conduit according to claim 85 or 86, wherein the continuous fibers are arranged in one or more directions.

88. The medical gas conduit according to any one of claims 85 to 87, wherein the continuous fiber is partially embedded in the elongated tube.

89. A medical gas conduit for delivering a flow of medical gas in a medical gas system, the medical gas conduit comprising: A slender tube defining an inner cavity through which the medical gas flows; and A pair of connectors, disposed at respective ends of the elongated tube, the pair of connectors being configured to pneumatically couple the medical gas conduit to other components of the medical gas system, the connector of the pair of connectors including a pair of orifices.

90. The medical gas conduit of claim 89, wherein the pair of orifices are arranged with their diameters opposite each other.

91. The medical gas conduit of claim 89 or 90, wherein the pair of orifices extend together beyond 80% of the circumference of the connector.

92. The medical gas conduit according to any one of claims 89 to 91, wherein the medical gas conduit includes a sheath disposed around the outer surface of the elongated tube.

93. The medical gas conduit according to claim 92, wherein the sheath comprises a braided sheath.

94. The medical gas conduit of claim 92 or 93, wherein the sheath is exposed through the pair of orifices.

95. The medical gas catheter according to any one of claims 92 to 94, wherein the sheath is securely attached to the elongated tube via the connector.

96. The medical gas conduit according to any one of claims 92 to 95, wherein the connector is at least partially overmolded into the sheath and the elongated tube.

97. The medical gas conduit according to any one of claims 89 to 96, wherein the connector is formed of two parts.

98. The medical gas catheter according to any one of claims 89 to 97, wherein the connector comprises: The first part is injection molded; and The second part is overmolded onto the first part.

99. The medical gas conduit of claim 98, wherein the second portion is overmolded onto the first portion, the elongated tube, and the sheath, the sheath being disposed around the outer surface of the elongated tube.

100. The medical gas catheter according to any one of claims 32 to 99, wherein the length of the medical gas catheter in equilibrium is between about 0.8 meters (m) and 2.5 meters, and optionally: Between approximately 0.8m and 1.4m, or between approximately 1.0m and 1.4m, for example, approximately 1.2m; or Between approximately 1.2m and 2.0m, or between approximately 1.4m and 1.8m, for example, approximately 1.6m.

101. The medical gas catheter according to any one of claims 32 to 100, wherein the medical gas catheter does not include at least one of the following, and optionally does not include two of the following: Heater (e.g., heating wires or water jacket); or Water collector.

102. The medical gas conduit according to any one of claims 32 to 101, wherein at least a portion of the medical gas conduit comprises a breathable material, which, in use, is configured to expand along one or more of the radial direction, the longitudinal direction, or the wall thickness due to the absorption of water molecules.

103. The medical gas conduit according to any one of claims 32 to 102, wherein the elongated tube is configured to absorb at least 33%, about 33% to 200%, about 100% to 160%, about 120% to 140%, or about 130% to 135% (e.g., 133%) of its own mass of water molecules in an immersion test.

104. The medical gas conduit according to any one of claims 32 to 103, wherein the elongated tube is configured to expand at least one of the radial direction or the longitudinal direction in an immersion test, and optionally each expands by at least 20%, about 20% to 70%, about 25% to 50%, or about 30% to 50%.

105. The medical gas conduit according to any one of claims 32 to 104, wherein the breathable material comprises a block polymer, the block polymer optionally comprising one or more of the following: Polybutylene terephthalate hard segments; or Polyether-type macromolecular diol soft segments.

106. The medical gas catheter according to any one of claims 32 to 105, wherein the medical gas system includes a respiratory support system, and the medical gas catheter includes an expiratory catheter configured to deliver respiratory gases from a patient during use.

107. A medical gas circuit kit, the medical gas circuit kit comprising a medical gas catheter according to any one of claims 32 to 106, and any one or more of the following: Humidifier supply pipe; Pressure reducing valve; Humidification room; Inspiratory duct; Multiple retaining components; Delivery catheter; Y-shaped parts; Insertion connector; Patient interface; catheter hanger; Expiratory tube; Discharge duct; Filter; or Pressure regulator.

108. The medical gas catheter according to any one of claims 32 to 105, wherein the medical gas system includes an anesthesia breathing system, and the medical gas catheter includes an expiratory catheter configured to deliver respiratory gases from a patient during use.

109. The medical gas catheter according to any one of claims 32 to 105, the medical gas system comprising a surgical inhalation system, and the medical gas catheter comprising an exhaust catheter configured to deliver inhaled gas from the patient during use.

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