Infusion apparatus

Abstract

A gas trapping device (100) for medical fluids as in an infusion system. The device has a chamber (101), an inlet section (103) to a bubble trap chamber with a plurality of entry ports (104, 105), and an outlet section with at least one exit port (110). The arrangement of the ports and chamber allows mixing of gases from different fluids, which are trapped in the chamber. The entry ports merge at an accumulation space, and the chamber includes a diffuser with apertures (107) around the inflow tube for the lateral dimension component of fluid flow into the chamber. The entry ports (104, 105) are between 1.5 mm and 8.0 mm in diameter, and the distance between the upper end of the accumulation space between each entry port (104, 105) and the apertures (107) of the diffuser is no more than 20 mm. This promotes turbulent flow as the fluids mix, which continues through the diffuser to increase bubble formation, causing the gases to migrate away from the outlet section as bubbles towards the upper end of the chamber in use.

Description

TECHNICAL FIELD

[0001] The present invention relates to a bubble trapping device suitable for medical applications, in particular for infusion of fluids in primary and secondary lines. BACKGROUND

[0002] During intravenous (IV) infusion, natural outgassing can occur, particularly when infusing two or more chemically incompatible fluids, resulting in the appearance of gas bubbles that can pose a threat to the health of the patient. In cases where toxic biological products or hazardous drugs are used, such as in chemotherapy, the released gas can also be toxic and should be retained within a safe chamber. In particular, the development of a closed system aspirator (CSA) would improve the current state of the art and improve safety in healthcare practice.

[0003] IV infusion of drugs is common in modern healthcare. The clinical action of combining fluid drugs directly into the vein is standard practice, particularly in the field of oncology where expensive or highly targeted doses of drugs are required. In this case, the amount of drug is critical and cannot tolerate fluid loss due to adhesion on the IV tubing. A primary fluid, usually normal saline (NS) or Ringer’s Lactate, is used as a carrier fluid to flush the maximum amount of drug into the patient’s vascular system. Secondary fluids can include a wide range of biological products, drugs or hazardous drugs (HD) such as Etoposide TM or Paclitaxel TM . Some drugs are not suitable for a particular type of tubing, such as PVC tubing, due to sidewall adhesion, and can benefit from lower friction characteristics when mixed as a solution with NS.

[0004] When two or more liquid drugs are combined into a mixture, a chemical reaction occurs. As a result of the chemical reaction, the drugs can elute or outgas. This outgassing can also occur due to turbulent reactions between the molecules of the liquid. Turbulence occurs due to the frictional reaction of the fluid as it moves over a surface, and the formation of water flow eddies as the molecules of the liquid rapidly change direction and interact due to changes in the surrounding geometry.

[0005] The fluid in these cases is a single phase combined of liquid, gas and plasma. When the fluid outgasses, bubbles of gas are released in the fluid. The formation of the bubbles is due to the pressure of the gas pushing outwards from the inside, while the surrounding water molecules tend to stick together and form a film. The greater the pressure of the gas on the bubble film, the larger the bubble that forms. In the case of bubbles interacting, the bubble films can coalesce and combine to form larger bubbles. In the bulk of the fluid, the bubbles are subject to the forces of the surrounding pressure, tending to float upwards under the action of buoyancy.

[0006] In use, certain mixtures or medications have gaseous and unstable properties due to their chemical structure. These fluids have a tendency to outgas and require a healthcare professional to take responsive action to reduce the risk to the patient. One important action is to remove the gas bubbles from the fluid. In cases where the gas bubbles are formed from toxic biologicals or hazardous medications, the resulting vapor has properties that can be harmful to human health. Exposure to these medication vapors should be avoided.

[0007] It is well known to provide 'piggyback' IV infusion setups that describe various connection devices and techniques for infusing additional medications into a primary line. A common setup is to infuse a maintenance fluid such as normal saline or Ringer's lactate as the primary fluid. Chemotherapy agents can be administered through a secondary port or a Y-port. The secondary fluid is infused into the primary fluid, sometimes referred to as "piggybacking." The secondary IV solution bag is hung above the height of the primary bag. The position of the IV solutions affects the flow rate of the IV fluid into the patient. The setup is the same whether the medications are administered by gravity or by an IV infusion pump. The setup of the equipment and the mixing ratio of the two fluids can affect the flow rate and the accuracy of the dose.

[0008] Up to 75% of chemotherapy agents are delivered intravenously in the form of hazardous drugs (HDs) that are antineoplastic, mutagenic, carcinogenic, and harmful to human health. Intravenous administered drugs can be classified into five categories based on their potential for harm: vesicants, desquamating agents, irritants, inflammas, and neutral agents. Closed system devices are used to minimize exposure of healthcare workers handling these HDs and the associated adverse effects. Closed system transfer devices (CSTDs) are defined as "a drug transfer device that mechanically prohibits the transfer of environmental contaminants into the system and the escape of hazardous drug or vapor concentrations out of the system" [NIOSH 2004]. While there are many forms of CSTDs that can transfer medications into an IV system, there is still a need to efficiently remove problematic gas bubbles while still protecting the surrounding environment from exposure.

[0009] Multiple intravenous (IV) infusions to patients via infusion pumps occur frequently in healthcare. When problem air bubbles form in the IV tubing, the function of the pump is interrupted. Modern IV pumps use sensor technology to observe air bubbles in the tubing and stop the infusion, which can result in dosing errors, inefficiencies, and loss of drug efficacy in cases where short half-life is a drug characteristic. Microbubbles are small air bubbles with diameters between 10 and 50 pm, getting smaller and smaller, and finally disappearing under water. Ordinary bubbles have diameters from 1 pm and larger. Removing ordinary bubbles and microbubbles from IV tubing will help improve drug delivery, accuracy, safety, and efficiency of healthcare time. Air bubbles in intravenous infusions often cause infusion pump devices to sound alarms, creating noise pollution, which is a major cause of alarm fatigue for healthcare professionals. Therefore, removing these naturally occurring air bubbles before they reach the IV pump can have a beneficial impact on healthcare work.

[0010] When two infusion lines are joined together, a Y-connector device is often used. This device can be in the form of a rubber stopper and spike, or can be in the form of a male Luer to female Luer connection. In the case of HD, it is more common to use a Luer-Luer connection to minimize the risk of disconnection or improper sealing between components that would allow vapor to be vented to the atmosphere. Many hospitals and health agencies prepare HD in a controlled pharmacy with adequate ventilation, but the operation of removing problem air bubbles is performed at the bedside. The attending nurse often uses a syringe and manual manipulation techniques to tap or flick the IV line to displace the air bubble to the junction, where the air bubble is manually removed by drawing the bubble and a small amount of fluid into the syringe. This requires close contact with the HD vapor, with potential for spillage and waste of critical drug amounts. The operation required to remove the air bubble is often performed by nursing staff using inappropriate tools and non-standardized techniques, which can expose the nurse to risk of exposure and injury. SUMMARY

[0011] The present invention addresses the above problems.

[0012] Summary

[0013] We describe a gas trapping apparatus as recited in claim 1 as appended hereto, and various aspects of the apparatus as recited in claims 2 to 26. We also describe methods of use as recited in claims 27 and 28.

[0014] Additional statements

[0015] We describe a gas trapping apparatus for medical fluids, the apparatus comprising: a chamber; an inlet portion leading to a bubble entrapment chamber and having a plurality of entry ports; and an outlet portion having at least one exit port.

[0016] Preferably, the apparatus comprises a flow diverter in the chamber, the diverter being arranged to divert flow from the inlet portion to have a radial or transverse component relative to the direction of flow from the inlet portion. Preferably, the diverter is shaped to cause flow to divert away from the inlet portion and radially before it passes over the diverter and can move radially inwards towards the outlet portion. Preferably, the entry ports are adapted to allow mixing of fluids as they enter the chamber.

[0017] Preferably, the chamber houses the diverter and the entry ports are adapted to allow mixing of fluids before they encounter the diverter. Preferably, the entry ports comprise dedicated vent ports. Preferably, the inlet portion comprises a flow barrier to induce turbulence.

[0018] Preferably, at least one entry port comprises a flow barrier to induce turbulence. Preferably, the chamber comprises a hydrophilic membrane. Preferably, the membrane is mounted at the distal end of the diverter.

[0019] Preferably, at least one port comprises a valve for fully or partially closing the port, in some examples, a plurality of valves interconnected to operate synchronously. Preferably, the apparatus further comprises a membrane, preferably selectively sealable, to maintain the integrity of a closed system when an external device is connected to the port for transferring liquid or gas into or out of the chamber.

[0020] We also describe an infusion apparatus comprising a gas trapping apparatus of any of the examples described herein, preferably connected to a primary line and a secondary line.

[0021] We also describe a method of using the apparatus described herein, the method comprising the steps of: directing flow of different fluids distally towards the outlet portion via the entry ports and in the chamber, wherein gas from the plurality of fluids in the chamber is mixed and entrapped. Preferably, the method comprises the further step of: aspirating gas via the entry ports or dedicated vent ports. BRIEF DESCRIPTION OF DRAWINGS

[0022] The application can be more clearly understood from the following description of some embodiments thereof with reference to the appended drawings, given by way of example only and in which:

[0023] Figure 1 is a view of an infusion system incorporating a trap at the junction of a primary line and a secondary line;

[0024] Figure 2is a schematic side view of a trap arranged primarily for laminar entry Figure 1 is a schematic side view of a trap;

[0025] Figure 3 is a schematic side view of a trap arranged primarily for turbulent entry;

[0026] Figure 4 is a schematic side view of a trap arranged primarily for venting of the primary fluid using secondary ports;

[0027] Figure 5 is a schematic side view showing that the trap has a dedicated vent port for venting of the combined primary and secondary fluid solutions;

[0028] Figure 6 is a schematic side view of an entry port assembly for primary and secondary infusion ports;

[0029] Figure 7 is a similar view of an entry port assembly having three entry ports and a selectively sealable membrane;

[0030] Figures 8(a), (b) and (c) are views of a trap incorporating a hydrophilic membrane material for capturing and retaining artefacts;

[0031] Figures 9(a) and (b) are views of a trap having a number of staggered entry ports;

[0032] Figure 10 is a set of views of a trap arranged to be fixed in position relative to an IV pole, or arranged to be fixed;

[0033] Figures 11(a), (b), (c) and (d) are various views of a trap arranged to include a valve for controlling the flow of material between the primary and secondary ports, and the flow of material into the chamber from each port;

[0034] Figure 12(a) and 12(b) is a view of a trap device having a manifold for joining a plurality of lines;

[0035] Figure 13 is a view showing the ports and their sealing arrangements; Figure 14 shows an alternative port end cap having a better sealing engagement; and Figure 15 and 16 are plan views of further alternative port end caps, in this case having notches for engagement by a tool;

[0036] Figures 17 to 19 is a perspective view showing an alternative port, in this case having the end cap linked by a strap member;

[0037] Figure 20 is a set of side and cross-sectional views of an alternative port, in this case having Luer threads; and

[0038] Figure 21 and 22 is a side view of an alternative port, in this case having threads and a connecting strap member. DETAILED DESCRIPTION

[0039] We describe infusion apparatus and gas / bubble trapping apparatus for use with infusion apparatus. The trap has two or more liquid inlets and retains bubbles and gases generated thereby in the trap in a manner that is safe for medical personnel, whereby the trap can prevent the escape of undesirable gases to ambient air. In addition, in various examples, the trap allows for the safe removal of gases and, in methods of operation, the trap allows for the neutralization of unsafe gases.

[0040] The apparatus is suitable for the infusion of primary and secondary medicaments, alone or in combination, and collects gas bubbles entrained in the liquid in a sealed chamber. There is a housing to define at least one chamber, at least one inlet port, and an outlet port. To mix the incoming fluids, there are preferably multiple inlet ports.

[0041] The bubble trap has a chamber that is spherical in some examples. The inflow tube transports fluid by radial deflection by a diverter that is preferably conical. The outflow tube has an inlet that is downstream of the diverter and thus less likely to receive any bubbles that are deflected by the diverter. The inflow tube preferably has a diffuser upstream of the diverter, such as a ring of holes around the perimeter of the inflow tube. Liquid and gas will diffuse out through the diffuser, which tends to limit the flow so that the flow is more controlled laterally relative to the diffuser, thereby causing any bubbles to collect on the inner surface of the chamber and away from the inlet of the outflow tube.

[0042] Generally, the apparatus has a housing that defines at least one chamber, the chamber having an inlet portion and an outlet portion; a diverter in the chamber is between the inlet portion and the outlet portion. The outlet portion is preferably provided by an outflow tube having an entry within the chamber. The inlet portion provides a longitudinal direction into the chamber, and the diverter causes flow to be diverted laterally relative to the direction. The outlet portion is preferably aligned with the inlet portion, or the outlet portion can also be angled to the inlet portion. The entry of the outflow tube is within the chamber. The diverter preferably includes a base and a rim, and the diverter preferably defines a downstream-facing volume into which bubbles are less likely to enter. The entry of the outflow tube is preferably within a central volume defined by a range of 40% to 60% of any dimension across the chamber.

[0043] In various examples:

[0044] A portion of the inflow tube abuts or is integral with the diverter;

[0045] The diverter has a rounded profile;

[0046] The device includes at least one vent port adapted to clear trapped gas bubbles from the device;

[0047] There is at least one vent port adapted to clear trapped gas bubbles from the device;

[0048] There can be a vent port coupled to a release device operable to move between a closed position and an open position; such that, in use, trapped gas is cleared from the chamber of the device through the vent port when the release device is in the open position;

[0049] The at least one vent port is adapted to clear trapped gas bubbles from the device;

[0050] The release device is automatic;

[0051] The vent port comprises a gas-permeable water-impermeable membrane; such that, in use, trapped gas passes through the gas-permeable water-impermeable membrane and is cleared from the chamber, while water is retained within the chamber of the device;

[0052] The chamber is spherical;

[0053] The device is arranged in a circuit or infusion system for delivery to a patient;

[0054] The device includes a plurality of chambers arranged in series;

[0055] The chamber and diverter have an inner surface having a surface treatment for hydrophilic control of bubbles and their movement within the chamber;

[0056] The rim of the diverter surrounds the intake end of the discharge tube;

[0057] The device includes a gas-impermeable and liquid-permeable membrane at the intake end of the discharge tube;

[0058] The device includes a filter for removing particulates before liquid enters the intake end of the discharge tube.

[0059] We also describe an intravenous line set comprising at least one intravenous drip bag, at least one drip chamber; at least one supply tube having a proximal end and a distal end; a bubble trap; a fluid flow control device; at least one clamp; and a cannula; wherein the bubble trap comprises:

[0060] a housing defining at least one chamber, the chamber having an inlet port and an outlet port;

[0061] an inflow tube having an intake end and an output end, the output end being located within the chamber;

[0062] a diverter located between the inlet port of the chamber and the outlet port of the chamber, wherein the diverter comprises a base and a rim;

[0063] a discharge tube having an intake end and an output end, wherein the intake end of the discharge tube is located within the chamber and the output end of the discharge tube is connected to the outlet port of the chamber; and

[0064] a diffuser located in the inflow tube between the inlet port and the diverter, wherein the diffuser comprises at least one aperture in the inflow tube and is configured to cause an alternative direction of motion of fluid entering the chamber in the inflow tube.

[0065] The above features are in some examples combined with an inflow conduit that provides for the merging of different flow streams upstream of the chamber or within the chamber but upstream of the diverter within the chamber, as described in more detail below.

[0066] The inlet portion preferably comprises multiple inlet ports for mixing different fluids for optimal patient administration. A primary advantage of the bubble trap is to prevent bubbles from flowing out of the outlet portion, even if abnormally high gas levels occur due to mixing fluids via different ports.

[0067] There can be a vent port, which is preferably sealable by an end cap. There can be a diffuser channel for separating infusion fluid or actively combining fluids to accelerate degassing. There can be a diffuser portion that controls bubble behavior as bubbles enter the chamber. A diverter can be positioned between the inlet port and the outlet port so that the direction of fluid flow can be controlled.

[0068] There can be a self-sealing membrane that enables fluid or gas to be pushed into or pulled out of the chamber via one of the infusion ports or the vent port.

[0069] There can be an elongated discharge tube having an intake end located in a most central region of the chamber, the output end of the elongated discharge tube being connected to the outlet port of the chamber.

[0070] We also describe a closed system aspirator device having some or all of the above features. Referring to Figure 1 , a 'piggyback' IV infusion setup 1 has a primary fluid bag 2, a secondary fluid bag 3, a piggyback set 4, a primary set 5, a roller clamp 6, a Y-connector port 7, an IV pole 8, a clamp 9, an infusion tube 10, and a bubble trap device 100. Figure 1Various connection devices and techniques for infusing additional medications are shown. The chamber can be completely sealed so that the chamber can retain all fluids or gases. The bubble trap apparatus 100 will be described below, but in general, the apparatus can include any of the features of the various examples described herein.

[0071] Referring to Figure 2 The trap 100 has a spherical chamber 101 and an inlet section with first and second entry ports 104 and 105 leading to a frusto-conical diverter 102. This arrangement is primarily to smooth the fluid vortex and to convert turbulent flow to laminar flow in the inlet section passageway. The arrows show the gas bubbles flowing upward from the diffuser holes 107, the liquid flowing into the inlet 111 of the outflow tube 110, and out through the outflow tube 110. This trap apparatus can be used to receive different fluids mixed in the chamber 101, and the gas bubbles migrating upward can coalesce to reduce the hazard and, in any event, are trapped in the chamber 101.

[0072] The trap 100 has a spherical chamber 101 and an inlet section with first and second entry ports 104 and 105 leading to a frusto-conical diverter 102. This arrangement is primarily to smooth the fluid vortex and to convert turbulent flow to laminar flow in the inlet section passageway. The arrows show the gas bubbles flowing upward from the diffuser holes 107, the liquid flowing into the inlet 111 of the outflow tube 110, and out through the outflow tube 110. This trap apparatus can be used to receive different fluids mixed in the chamber 101, and the gas bubbles migrating upward can coalesce to reduce the hazard and, in any event, are trapped in the chamber 101.

[0073] This arrangement induces and promotes turbulence in the mixing of the fluids and this turbulence continues through the diffuser to accelerate the degassing of the mixture to enhance the subsequent bubble formation and thus the migration of the gas as bubbles away from the outlet section toward the upper end of the chamber in use.

[0074] The chamber volume is optimized to hold more or less than 10 milliliters of fluid under full primed conditions, with the ability to retain up to 50% of the volume in gaseous state, as the bubbles rise under the pressure exerted by the fluid body. The inlet section advantageously provides a collection site for different fluids, positioned at a distance immediately upstream of the diffuser (107), measured as at least equal to the inner diameter of the inflow tube (104, 105), which is useful for common practices in conjunction with and administration of fluid pharmaceutical formulations, so that the formed bubbles immediately flow laterally out.

[0075] Figure 3 A trap 100 is shown, primarily arranged for turbulent flow entry, with helical barriers 120 in the entry ports 104 and 105. Like parts are indicated with like reference numerals.

[0076] Reference is made to Figure 4 The trap 200 is primarily arranged to aerate the primary fluid using a secondary port. It comprises a chamber 201, a diverter 202, an inlet section 203 with entry ports 204 and 205 and diffuser holes 207, and an exit port 210 with an inlet 211. In this case, the entry port 204 is used to aerate the primary fluid delivered via port 205. In many examples, it is particularly advantageous that the second entry port is open so that it can vent gas entering via the other entry port. This arrangement is particularly suitable where gas can be safely vented to the environment, providing flexibility to the second port and the aerating port. The entry port 204 can be capped or sealed by a selectively openable cap 208, if needed. The cap 208 can be opened if port 204 is to be used as an inlet for additional fluid. In scenarios where the fluid is toxic, such as chemotherapy preparations, the cap 208 can be marked with a color or design to indicate that it is not suitable for reopening.

[0077] Reference is made to Figure 5 The trap 300 has a similar configuration of chamber and diverter, and an inlet section 303 with three ports 304, 305 and 306. Two of the inlets can be used for inflow of fluid, while the third is selectively used as a dedicated venting port for safe removal, to aerate the combined primary and secondary fluid solutions. Port 306 has a removable cap 307 for selective venting.

[0078] Figure 6An integral component 400 is shown that is installed to the chamber during manufacture. The component 400 has access ports 404 and 405 and a frustoconical diverter 402, and also a diffuser opening 407 for fluid flow with a radial component into and around the diverter 402. An integral component like this provides for simple and accurate assembly.

[0079] Referring now to the drawings Figure 7 An integral access port assembly 500 has primary and secondary infusion ports 504 and 505, and a third port 506, all converging at a diffuser 507 at the base of a diverter 502, with opening 505 therebetween. The component has a selectively sealable membrane in one or more of the infusion or vent ports 504-506. The membrane is activated by insertion of a compatible needleless connection device. A normally sealed or self-healing membrane is intended to maintain the integrity of the closed system when toxic gases are vented from the chamber to a selectively attached, closed system transfer device with needleless connectivity. The membrane also maintains the closed system for direct introduction of medication into the chamber through the ports via a closed system transfer device, a conventional syringe, tubing or any other suitable device. Such a membrane can be formed of rubber, silicone or other material that can be elastically deformed and return to normal shape. Such a membrane that is normally closed but can be deformed to allow fluid passage through the channel can be acted upon by a needleless connector to force the normally sealed membrane to deform and open its channel so that liquid can pass. In this case, liquid can be injected into the chamber or withdrawn from the chamber by actuating a needleless syringe. Similarly, any other device or IV tubing with a suitable needleless connector can be attached by means of a Luer connection or push fit or other connection. Once the needleless connection device is withdrawn, the self-healing membrane, such as B Braun's The needleless connector will return to its normally closed position to seal the port. The port can be further protected by closure of a plug or cap that can be achieved by pushing, twisting or pressing into place, or any other method of sealing the end of the port.

[0080] Referring to Figures 8(a), (b) and (c), the trap 600 has a spherical chamber 601, a conical diverter 602, an outflow tube 610, and inlet ports 611 and 612. The trap 600 also includes a hydrophilic membrane 603 for capturing and retaining artifacts. The trap includes the chamber 601, the diverter 602, and an inlet section 600 with inlet ports 611 and 612. The membrane 603 is below the diverter 602, and the membrane includes a fine fiber mesh to form a fabric of material such as PTFE with micron-sized openings to allow only fluid particles to flow through while capturing solid or gas particles of size larger than the mesh openings. Hydrophilic membrane materials are commonly used in the healthcare field to prevent particles of size greater than 0.2 microns and artifacts from entering a patient's blood. In the illustrated embodiment, the membrane is attached to the base of the conical diverter 602 and abuts the opening of the outflow tube 610, and the membrane can be sized to ensure that the gap between the diverter and the outflow tube is sealed. In another embodiment, the membrane can be stretched across the opening of the outflow tube 610 within the chamber 601.

[0081] Referring to Figures 9(a) and (b), the trap 700 has a chamber 701 with a diverter 702 and an inlet section 703 with several staggered inlet ports. In this case, there are inlet ports 703, 704, 705 and 706, and in this case, a single inlet conduit 708 has two ports (704 and 705). This arrangement has excellent flexibility, especially in that multiple fluid lines can be attached away from the diverter 702, with the benefit that phase separation can occur by flowing through a diffuser 707 and over the diverter 702 at a later point of entry into the chamber. Port 703 is for primary inflow, port 706 is for secondary inflow, and ports 704 and 705 are for additional inflow. In the case of a single conduit having multiple ports fed to it, compactness and simplicity of manufacture are achieved. Preferably, the ports closest to the chamber, i.e., ports 703 and 706, are used in typical use, while the more distant ports 704 and 705, in communication with the single conduit 708, are used in special cases. Any or all of the ports have end caps 709 for selective sealing.

[0082] Figures 10(a) and (b) are a set of views of traps arranged to be fixed in position relative to the IV pole, or arranged to be fixed. Trap 800 has mounting clips 801 arranged to encircle the pole, and trap 805 also has such brackets, but with a different arrangement of entry ports. Trap 810 has mounting clips 811 half way between the inlet and outlet, shown mounted to the pole P. Manifold trap 850 has a pair of mounting clips 851 and 852 arranged to support both the chamber 860 and the elongate entry port 853 to the pole, the elongate entry port having an entry conduit 861 and a number of entry ports 854 extending radially from the conduit 853. Device 850 is fixed to the chamber 860 at the lowermost end position, so that fluid flows in through the manifold's multiple entry ports or entry conduit 861 to flow down through the chamber 860.

[0083] Referring to Figures 11(a) and (b), trap 900 has a chamber 901, diverter 902, and an inlet 903 with entry ports 904 and 905. In this case there is a plug valve 906 to control the flow between the entry ports 904 and 905, and into the chamber 901 from each port. Under manual control, the plug valve can completely or partially stop the flow from each port. The plug valve 906 is controlled by an external lever handle which rotates a barrel within a matching chamber along a central axis. Chamber 901 has a vent port 920. For the above embodiment, there is an outflow tube 910 with an inlet inside the chamber 901.

[0084] Referring to Figure 11(c), trap 950 has a chamber 951, diverter 952, outflow tube 960, and two entry ports 954 and 955 with a valve 956 at the convergence point. Valve 956 has a concave surface 957 and a concave surface 958. When the valve is pivoted to the relevant position, these surfaces provide a flow route, concave surface 957 allowing flow through port 955 when facing upstream of the entry port, and concave surface 958 allowing flow through port 954 when facing upstream of the entry port.

[0085] Figure 11(d) shows trap 970 with chamber 971, diverter 972, entry ports 974 and 975, and valve 976. Valve 976 has a barrel 985 with a transverse through hole 986 and a handle 987 to allow flow by pivoting the hole 986 into alignment with one port or the other.

[0086] The barrel portion is pressed into place until the groove is positioned and secured under frictional pressure. When sufficient force is applied in a rotational manner about a common central axis, the stopcock barrel rotates to allow selective opening or sealing of the passageway depending on the position of the passageway opening. The passageway allows fluid to flow through the stopcock barrel when aligned with the direction of the fluid path. When not aligned with the fluid path, the barrel wall forms a seal and does not allow fluid to flow through.

[0087] The stopcock instrument valve can be formed as a single molded plastic component with a low coefficient of friction.

[0088] Figure 12(a) shows a trap 1000 with a manifold 1001 having a plurality of individually controlled valves 1002 to control the proportion of mixing and flow into the inlet manifold 1001 and along the path to the chamber 1005. Figure 12(b) shows an alternative arrangement in which one end of the manifold 1050 is mounted to the chamber 1051.

[0089] End cap for hazardous drug / toxic biologic chamber

[0090] We describe below various vent ports having a vent opening and an end cap which is easily installed in place to seal the vent port, but which is not possible or difficult to remove. This allows initial venting to purge the line, but thereafter to seal as toxic fluid is administered. Where the end cap is configured to be difficult to remove, the end cap can have recesses so that it can be removed by tool rotation, but not by hand.

[0091] The features of such a vent opening can be applied to bubble traps having only a single inlet port, and not necessarily bubble traps having an inlet portion with multiple ports. Thus, this aspect of the invention is applied to any bubble trap having a bubble entrapment chamber.

[0092] Chemotherapeutic agents are toxic drugs, often used for medical treatment of a wide range of cancers. Chemotherapeutic agents are most commonly provided as intravenous injections, as liquid drugs directly infused into a patient's vein in a hospital, clinic or home environment. Chemotherapeutic agents are in the form of hazardous drugs, which are intended to destroy human cells to provide a treatment regime. Hazardous drugs can include a wide range of agents other than chemotherapeutic agents, including toxic biological agents or drugs with carcinogenic, mutagenic and anti-tumour properties, all of which are harmful to human health.

[0093] It is preferable to administer toxic biologies or hazardous drugs (HDs) in a closed system that does not allow environmental contaminants to be exposed to the line, nor does it allow toxic substances to be exposed to the surrounding environment. During intravenous (IV) infusion of drugs, minute amounts of toxic fluids can escape from the IV system and settle on the surrounding surfaces. These substances can be in liquid and / or gaseous form, and HD evaporation can be observed when exposed to the ambient atmosphere at room temperature. In modern healthcare, healthcare professionals are using devices known as closed system transfer devices (CSTDs) to ensure that HDs are administered without exposure, thereby ensuring the safety of patients and healthcare professionals. Adverse consequences of exposure to HDs in liquid or gaseous form can result in a range of health problems, including reproductive problems such as decreased fertility and increased risk of miscarriage, as well as dizziness, nausea, cancer, and death. It has proven that long-term repeated micro-dose exposure can directly result in harm to the health of healthcare professionals who are in close proximity to toxic biologic or hazardous drug infusions.

[0094] During drug administration, it is not uncommon to open the IV line to aspirate air bubbles from the HD infusion line, as these air bubbles pose a subsequent risk to the health of the patient. In removing air or toxic vapor bubbles, healthcare professionals place their own health at risk. It is evident that a device that reduces exposure can have a positive impact on healthcare services.

[0095] Maintaining the chamber closed is important to protect healthcare professionals and their patients from unknown or accidental contact with the chemotherapy products or toxic agents flowing through the IV. In the setup of an IV, such as priming, which excludes air entrained in the IV tubing to ensure that the procedure is performed correctly and safely, it is necessary to have an open port to vent the air. In the case where the device is used to clear problematic air bubbles in the IV line, then a vent port is required to vent the air, in the IV line, the chamber is intended to retain liquid and gas. The purpose of the open port is to allow air to be expelled from the chamber so that the required volume of fluid can enter the chamber. Once the chamber is full of the required fluid, it is necessary to seal the chamber so that the drug is not exposed to an unsafe environment, such as at the bedside. In the case of blood or hazardous drugs being administered, it is generally more preferable and safer to ensure that the chamber cannot be easily opened to ensure there is no risk of exposure to the toxic drug.

[0096] Accordingly, a method of ensuring a reliable seal will potentially reduce the opening of the chamber. Preferably, the end cap cannot be opened or removed by hand. Such a device, when secured in place, will provide an air-tight seal to ensure that no liquid or vapor can pass into or out of the chamber.

[0097] The end cap can be a push fit, twist or latching mechanism, or any other mechanism whereby the end cap can be placed in an active position and not easily removed. The end cap can be fixed in place, or can be selectively sealable, such that the end cap can be opened to allow critical functions to be performed. The end cap can seal off passage of fluids, vapors and environmental contaminants by press fit contact between mating surfaces, or can also utilize a sealing ring or membrane device.

[0098] Referring to Figure 13 The vent port 2100 includes an end cap 2101 that mates with a vent opening 2110, which is intended to seal the chamber opening 2110 in a manner that is difficult to open. The seal 2100 can form part or all of a trap chamber that contains fluids therein that are intended to be isolated from the internal and external environment. By placing the end cap 2101 in place, the opening 2110 is completely sealed by a gas tight seal, and no fluids can pass through. The end cap 2101 can be pushed into place, twisted, squeezed or otherwise forced into the orifice.

[0099] In this embodiment, the end cap 2101 includes downwardly depending legs 2106 that are separated by a V-shaped gap 2103 to provide a split feature that is intended to flexibly deform when pushed into the mating vent opening 2110 of the chamber. The mouth of the opening 2110 has a radially inwardly directed rim or protrusion 2105 that locks into position with a peripheral groove 2104 in the end cap 2101. When fully in place, the downwardly and inwardly angled walls of the legs 2106 of the end cap base contact the inner surface of the walls of the chamber opening 2110 to form a gas tight seal. The top of the end cap 2101 has a convexity 2108 that is intentionally difficult to grasp, reducing the potential for the end cap to be removed by hand, such that the end cap 2101 and the chamber 2111 are forcibly sealed and held together to form a sealed unit.

[0100] Figure 14 is a set of views of an alternative vent port 2200 with an end cap 2201 and vent opening 2210. In this case, the end cap 2201 has legs 2206 that are tapered inwardly on their outer surfaces to narrow on one end that is inserted into the opening 2100, and are separated by a V-shaped gap 2203. Again, there is a circumferential groove 2204. However, in this case, the top 2208 has a lower profile, with a shallow depression 2209 that spans the lower profile in diameter. In addition, there are additional circumferential grooves 2215 and 2216 below the groove 2204. The opening 2210 has corresponding ridges 2210, 2211 and 2212 to tightly engage with the grooves 2204, 2215 and 2216.

[0101] In other examples, there can be a pair of cross-shaped cutouts similar to cutout 2203 to allow for more even flexibility across the perimeter.

[0102] As shown in FIGS. 23A and 23B, end cap 2301 can have a diametrically extending slot 2302 for the tool to grip, or end cap 2401 can have a cross-shaped groove 2402 for the tool to engage. Figure 15 16 As shown in FIGS. 23A and 23B, end cap 2301 can have a diametrically extending slot 2302 for the tool to grip, or end cap 2401 can have a cross-shaped groove 2402 for the tool to engage.

[0103] End caps with a crack base can have any of a variety of shapes and materials. Some materials can be chosen for their low or high coefficient of friction properties or elastic properties such that the material can deform or flex as desired to accommodate the opening. The crack can be any of a variety of notch shapes to achieve flexible deformation. The material can be required to return to its given geometry once the force is removed.

[0104] The end cap top can be the same or different material as the end cap base. The shape of the end cap top can be round, flat, convex, concave, or any other geometry that is intentionally difficult to grip or pull.

[0105] As described above, the end cap can have one or more notches that interface with protrusions such that when the notch moves past the top edge of the protrusion, the end cap is rigidly held and locked into place with friction or surface-to-surface contact.

[0106] For convenience, it is useful to position the end cap on or near the device that needs to be closed. In Figure 17 Figure 18 In one embodiment, as shown in FIGS. 25A and 25B, end cap 2501 is attached to opening 2510 of chamber 2511 by means of a flexible connector or strap member 2530 such that the end cap can be maneuvered into the opening. The strap member can be attached to the chamber by means of bonding, joining, clamping, or molding. In this case, end cap 2501 is attached to the opening by strap member 2530 through a loop 2531 that slides over opening 2510. The purpose of the loop is to enable the end cap to be twisted into place or pushed into place, the loop can be rotated to a convenient position, and the strap member 2530 will not be cut or twisted.

[0107] In Figure 19 ​​In one embodiment shown, the strap member 2530 includes a loop 2531 at the inner end for engaging the opening and a disc 2533 at the outer end for engaging the end cap. These ends are connected by a band 2532 which has a narrowed geometry or neck 2534 and 2535 at the inner and outer ends respectively. These form a weak link so that once the end cap is in its permanent position, the end cap can be easily pulled and disconnected by hand or a suitable tool. The reason for removing the strap member is to make it less easy for the end cap to be pulled and removed from its permanent position intended as a seal.

[0108] During priming, the end cap can be put into its permanent starting position to seal the chamber and the strap member can be partially broken to indicate that the chamber is sealed. In one embodiment the material is flexible, in another embodiment the material is rigid, in another embodiment the material is a bright color to identify its position.

[0109] In another embodiment, the end cap is formed with internal threads of the common Luer type so that the end cap can be rotated and sealed in place on the outside portion of a Luer fitting, a common practice in medical procedures.

[0110] In another embodiment, the end cap is formed with a push fit portion that is sealed in place on the outside portion of the push fit portion using surface-to-surface frictional contact.

[0111] In Figure 20 Another embodiment is shown in FIG. 26 in which a sealed end cap 2601 is connected to a port opening 2610 by Luer threads 2605 that mate with threads 2613 on the outside surface of the port, i.e. the outside surface of the opening 2610. The end cap 2601 has a split 2603 on the inside portion that is intended to deform and narrow when the radially outward end cap surface 2606 comes into contact with the port opening edge 2611. When fully rotated into place, the inside end cap surface 2604 comes into contact with the port surface 2612 and the end cap 2601 is trapped on the port opening 2610 as the flexible port expands. When the end cap 2601 is rotated on the Luer threads, it remains fixed in its permanent position due to the inside split portion being trapped by the contacting surfaces 2604 and 2612 and the end cap is essentially not removable once in place. The outside surface of the end cap 2601 has a hand grip knurl 2608 to support initial tightening of the end cap device by hand.

[0112] In another embodiment, the end cap can be attached by bonding, joining, molding or some other process so that the end cap is always connected to the device with the open port.

[0113] In Figure 21In another embodiment shown, the end cap 2700 has many features comparable to those of the end cap 2701, but in this case, the end cap 2701 is linked to the opening 2710 by a strap member 2730. Figure 20 A variation is shown in which the end cap 2800 has an end cap 2801 similar to the end cap 2701, except that it has a pair of narrow knurled gripping surfaces 2801 and 2802 separated by a ring 2831 integral with the strap member 2830. Figure 22 A variation is shown in which the end cap 2800 has an end cap 2801 similar to the end cap 2701, except that it has a pair of narrow knurled gripping surfaces 2801 and 2802 separated by a ring 2831 integral with the strap member 2830.

[0114] Use

[0115] The use of any of the devices described herein is described below. Fluid enters the chamber through the primary inflow port and is diffused into the chamber through a plurality of diffuser holes. The diffuser holes are located near the location where the inflow tube abuts the conical diverter, distal to the conical diverter, such that fluid enters the chamber via the inflow tube, through the diffuser holes, and over the conical diverter. These one or more diffuser holes can be circular, oblong, or slot-shaped, arranged on the body of the device such that the sum of the diameters of the plurality of holes equals the diameter of the inflow tube, so as not to affect the flow rate into the chamber. Where desired, the primary fluid can also be combined with fluid from the secondary inflow port prior to diffusion into the chamber, which can facilitate mixing and aspiration of the two fluids. When the device forms part of an IV administration system, the fluid can flow by gravity, or can be induced by a pump or any other means of inducing flow rate.

[0116] The primary advantage of allowing the primary inflow and secondary inflow to enter the chamber and mix within the chamber is that any naturally occurring outgassing is prohibited from entering the tubing distal to the device. The device can act as an inline air aspirator, facilitating the efficient release of gas entrained in the liquid phase. Since the release of gas from the various fluids is controlled within the enclosed chamber, the risk of gas entering the outflow port is low. The advantage of this is that the inline air alarm of electronic IV pump devices, which monitors the fluid for problematic air bubbles, is significantly reduced, and the interruption of medication delivery that can result from the inline air alarm is also reduced.

[0117] Another advantage is that the attending caregiver is less required to intervene in the normally closed system to spend less time manipulating gas to a convenient location for removal, and no additional devices are required to aspirate trapped gas, resulting in efficient and lower cost benefits to the healthcare institution. Another advantage is that harmful drug vapors are retained within the sealed chamber of the device, protecting healthcare workers from exposure to toxic drugs.

[0118] Having multiple infusion ports on the enclosed body device allows for administration of the mixed solution without the presence of problematic air bubbles in the mixture.

[0119] Diffusing the solution into the chamber promotes buoyancy to overcome the flow rate of the fluid, such that any air bubbles are forced to rise more easily to the top of the fluid. By diffusing the air bubbles and allowing the microbubbles to coalesce together as they enter, the effect of buoyancy is increased. The advantage is that the air bubbles are less likely to flow into the body of fluid in the chamber and instead tend to float to the air-liquid interface region, where the bubbles will collapse.

[0120] Another advantage of the device is that the use of the tapered diverter reorients the particles of the fluid to the outer edge of the body of fluid as it enters the chamber. At the outer edge of the chamber, any entrained air is furthest from the intake end of the outflow port, and as the particles slow in their motion, laminar flow is induced to occur, such that the air bubbles are more likely to rise under the effect of buoyancy. Furthermore, any entrained particles are more likely to fall to the lower part of the chamber, furthest from the outflow port.

[0121] The primary inflow is used to flood the chamber with the primary fluid. In this case, the outflow port can be closed by means of a plug or clamp to prevent outflow from this port, and the secondary inflow tube opened to allow a pressure differential to occur, thus prompting the primary fluid to flow into the chamber and expel all entrained air from the open secondary inflow tube. The secondary inflow tube can then be closed, for example by activation of an end cap, seal or plug. With the secondary tube closed, the outflow tube can be opened to establish a liquid pathway from the primary inflow tube to the outflow tube. Furthermore, the secondary inflow tube can in turn be attached to the secondary inflow port, such that a mixture of the primary and secondary fluids can be injected into the chamber and the combined solution expelled through the outflow tube.

[0122] In another embodiment, the vent port or secondary inflow tube can feature a membrane with normal sealing or self-healing properties. Such a membrane can be formed from rubber, silicone or other material that can elastically deform and return to normal shape. Such a membrane, which is normally closed but can be deformed to allow fluid to pass through the passage, can be acted upon by a needleless connector, forcing the normally sealed membrane to deform and open its passage so that liquid can pass. In this case, liquid can be injected into the chamber by a needleless syringe, a closed system transfer device with a suitable connector or other IV tubing can be attached by a Luer connection, or push-fit connection, or other connection means.

[0123] The advantage of having a normally sealed membrane at the secondary inflow port is that toxic liquids that can be contained in the secondary connection device can be passed into the chamber via the secondary inflow port, while maintaining a sealed system.

[0124] In one embodiment, the primary inflow tube and the secondary inflow tube are separated by a dividing wall to encourage a laminar flow profile such that each fluid enters the chamber in its own channel without mixing. These separate fluids diffuse into the chamber through a plurality of inlet port holes in the diffuser portion. One advantage of this embodiment is that the primary inflow tube can have an IV line attached and can be used to fill the chamber with fluid, while the independent secondary inflow tube can remain open as a venting port for entrained air until the chamber is fully primed. In use, the secondary inflow tube can be selectively sealed or the secondary inflow tube can have an IV line attached for secondary inflow, whereby the fluid flows into the chamber through the diffuser and diverter described previously.

[0125] In a further use, the primary fluid and the secondary fluid, or additional fluids, are mixed together prior to the diffuser. This mixing is intended to encourage outgassing between the liquids.

[0126] In another use, the separation of the liquid and gas phases of the fluid, as well as the particles and artifacts, can be accelerated by the addition of a vortex screw that directs the fluid flow toward the outer wall of the fluid channel in a rotational motion that encourages air and particles to move toward the outer regions of the fluid body. In this case, the outer regions of the fluid body are the most central regions of the chamber. When two or more fluids are combined in this manner, the particles collide with one another and form a turbulent mixing mechanism under which bubbles of various sizes are formed. These bubbles, along with the combined solution, enter the chamber through the diffuser holes and travel through the fluid body as intended, with the bubbles floating upward under the force of buoyancy and the particles sinking due to the relative weight of the fluid body.

[0127] In a further use, the artifacts can be prevented from entering the outflow port by the incorporation of a filter membrane that can be affixed to the surface of the diverter, the top of the outflow tube, or any other interior surface of the chamber. The advantage of using a filter membrane on the surface of the diverter is that the surface area is increased where clogging is less likely to occur, and the filter membrane can expand as intended without unduly affecting the intended flow rate, while preventing solid particles from entering the outflow tube to the pump or patient.

[0128] In one use, the primary inflow tube is connected to the air aspirator device by means of a Luer lock. In another embodiment, the primary inflow tube is connected to the air aspirator device by means of a push-fit. In another embodiment, the primary inflow tube is connected to the air aspirator device by means of a bonding such that the primary inflow tube is permanently affixed in place on the tubing.

[0129] In one use, the secondary and additional inflow tubes are connected to the air aspirator device by means of Luer lock. In another embodiment, the secondary and additional inflow tubes are connected to the air aspirator device by means of push fit. In another embodiment, the secondary and additional inflow tubes are connected to the air aspirator device by means of bonding, such that the secondary and additional inflow tubes are permanently affixed in place on the tubing.

[0130] In another use, the primary inflow port and the secondary inflow port are used only to infuse fluid into the chamber through the diffuser holes of the air aspirator device. In this case, there can be a separate vent port with a hole feature to allow entrained air to vent out of the chamber during priming, up the channel, and out only through the vent port. In this embodiment, the primary and secondary ports only allow inflow of infusion fluid. The primary and secondary ports are sealed with end caps, plugs, or other methods, or can also be filled with fluid in the event the vent port is open, creating a pressure gradient to force air to escape through the open port.

[0131] In another use, this vent port can include a self-healing, normally closed membrane as described previously. The advantage of this embodiment is that aspirated gas can collect in the upper portion of the chamber. When the collected gas is excessive, it can be desirable to vent the gas without stopping the infusion process. In this case, a suitable closed system transfer device (CSTD) can be attached to the vent port, which actuates the membrane to allow gas from the chamber into the CSTD and siphon the entrained gas into the device (e.g., CSTD, syringe, or other device) to exit.

[0132] The advantage of having a series of multiple inflow tubes is that it allows for more than one fluid to be infused through the air aspirator device at the same time. This can increase the efficiency of drug delivery, as well as provide the clinician with a single point of observation to monitor for air in the infusion line or other impediments that affect the overall delivery of IV fluids. Another advantage of this embodiment is the reduction in manufacturing steps and costs to provide a cost-effective solution for healthcare institutions.

[0133] In many applications, the primary line is back primed into the secondary line to purge the air initially entrapped in the secondary line. Typically, the secondary line is connected to the primary line by means of a Y-connector. The secondary fluid bag is held at a position lower than the position of the primary fluid bag, which forces the liquid into the secondary line. Using this method, the primary liquid is allowed to fill the entire secondary line. Once the air in the secondary line is completely purged, the position of the secondary fluid bag is raised to a position higher than the position of the primary fluid bag, which forces the liquid in the secondary line to dominate, and the liquid in the secondary line will flow into the primary line. In some cases, a mechanical IV pump is used to control the flow rate of the primary and secondary fluids. Thus, the primary fluid and the secondary fluid will flow into the chamber of the present invention as a mixture, and the air aspiration of the mixture will occur as described.

[0134] In one application, the primary fluid enters the chamber, the discharge port tube is clamped, which prevents flow in that direction; while the secondary port is opened, which promotes flow in that direction. As the chamber is primed with fluid from the primary line, the primary fluid fills the chamber and enters the secondary line through the diffuser holes, where priming of the secondary line will occur as described. The benefit of this is that it is normal clinical practice to back prime the secondary line in this manner to discharge entrapped air. The second advantage is that the entrapped air is discharged from the chamber upward through the secondary line and into the secondary IV bag, where the entrapped air is trapped to effectively maintain a closed system, which is essential for patient and staff safety. Once the chamber is primed and the secondary line is primed, the flow is reversed and the secondary line flows into the chamber as required to complete the treatment. The device can then be removed from the primary and secondary lines as described above to remove air bubbles.

[0135] In some applications, a two-way or three-way stopcock plug device is selectively opened or closed to create a passageway between the primary port, the secondary port, or the chamber. The advantage of including a two-way or three-way plug device is that it can conveniently control and prevent fluid flow from the primary line into the secondary line. Another advantage is that in the event of an adverse reaction to the drug in the secondary line by the patient, the port can be quickly and conveniently closed to stop further infusion of the drug. Another advantage of selectively opening and closing the port is that it can prime the secondary line before fluid enters the chamber. The combined fluid can then enter the chamber through the diffuser holes, and the air is aspirated as described.

[0136] Alternative embodiments

[0137] In one embodiment, the air aspirator device is self-contained and disposable. In another embodiment, the air aspirator device is an integral component of the primary administration set and can be used with the administration set as a disposable unit. In another embodiment, the air aspirator forms a solid shape. In another embodiment, the air aspirator is formed from sub-components manufactured by means of an injection molding process. In another embodiment, the sub-components of the air aspirator are assembled into a solid component.

[0138] In another embodiment, the air aspirator is assembled on the chamber portion with the purpose of capturing the aspirated gas. The air aspirator is located on the upper portion of the chamber so that all the fluid enters the chamber from the top and exits the chamber through the outflow port at the bottom end. The device can function in any orientation, therefore, the terms "top" and "bottom" are related to the inflow and outflow respectively and not in an absolute sense.

[0139] In another embodiment, the outflow port is elongated with the intake end of the outflow port located substantially in the center of the chamber. The elongated outflow port has the advantage of the intake end located in the center of the chamber that particles that collect in the fluid can be located at the lowest point of the chamber against the intake end of the outflow tube and can be restricted from entering the outflow tube. Other particles can be free floating in the liquid body due to buoyancy.

[0140] In another embodiment, a hydrophilic membrane is located against the intake end of the outflow tube to prevent the entry of floating particles or solid artifacts. In another embodiment, the hydrophilic membrane is attached to the base surface of the diverter body. The membrane is shaped to surround the intake end of the outflow tube to prevent the entry of floating particles or solid artifacts. In another embodiment, the surface of the diverter is polished to discourage bubbles from "sticking" or propagating on the surface of the diverter.

[0141] In another embodiment, the trap includes a chamber with attachment means that fixedly attach the device to a local surface. In practice, with the primary line attached to the trap, the inflow port of the air aspirator component is positioned in the uppermost position and the outflow port is positioned in the lowest position. The device can therefore be fixed in place by means of a split ring, a clamp or other fixation method. The device has the advantage of a fixed position in that additional infusion tubing can be easily attached and the device can be located at a height that is convenient for the clinical staff to use.

[0142] In another embodiment, the chamber of the trap is spherical. In another embodiment, the chamber is square. In a further embodiment, the chamber is long and strip-shaped. In another embodiment, the chamber is triangular.

[0143] The advantage of the device being spherical is that it enables the trapped gas to collect in any orientation away from the elongated vent tube. The advantage of the spherical chamber is that it minimizes the priming volume of the device, which can be important when infusing precious fluid resources such as pharmaceuticals or blood products. The advantage of the fixed position device being long and tall is that the chamber can hold a larger volume of gas.

[0144] In a preferred embodiment, the trap can move and rotate freely in any orientation and is not fixed in any particular position. In a further embodiment, the chamber is opaque. In a further embodiment, the chamber is translucent. In a further embodiment, the chamber is transparent.

[0145] One advantage of the chamber being transparent is that the formation of fluid and gas can be easily observed and monitored. In another embodiment, the device includes a measurement system. In use, the measurement system reads the amount or level of trapped air or collected gas bubbles in the chamber. In a preferred embodiment, the measurement system is a graduated scale.

[0146] One advantage of the measurement system is that the volume of gas present in the chamber of the device can be accurately measured. In another embodiment, multiple inflow ports can be turned on or off depending on whether or not a line of infusate is attached to transfer fluid into the chamber. In this case, each port would be able to be independently opened or closed with the aid of a plug mechanism.

[0147] The advantage of having a two-way or three-way plug is that each port can be cut off from communicating with the adjoining port and fluid loss can therefore be minimized. In the case of a line of infusate fluid being attached, the plug between the proximal port and the infusate port would be closed, ensuring that all fluid only enters the intended infusate port. When additional lines of infusate are added to the proximal port, the plug can be opened to enable mixing of the fluids. Fluid would flow freely from the uppermost port down through the multiple open ports and into the chamber located at the lowermost.

[0148] One advantage of placing the chamber in the lowest position is that all fluid will flow down into the chamber and the entrained gas can be released with maximum efficiency. Degassing of multiple fluid solutions will occur through the diffuser device in the ports and chamber. Gas will be trapped in the uppermost portion of the chamber while the bulk of the fluid will largely remain free of problematic gas bubbles.

[0149] In another embodiment, the apparatus is formed from a pliable material. In another embodiment, the apparatus is formed from a rigid material. In a preferred embodiment, the rigid material is a polymer. In another embodiment, the apparatus is formed from separate components. The constituent components require assembly to form the complete apparatus prior to use. In another embodiment, the apparatus can be manufactured as a single unit.

[0150] In another embodiment, the apparatus is manufactured by means of 3D printing. In another embodiment, the apparatus is manufactured by means of injection molding. In a preferred embodiment, the apparatus can be connected to various types of tubing (including various pumps) with standard connection methods. In another embodiment, the device is scalable in size, with the optimal size being assessed by the user according to the use case. In a preferred embodiment, the device can automatically capture and retain 1 cc or more of gas, and retain the gas in a sealed chamber. This is considered beneficial in cases of use of hazardous drugs or toxic biological products (such as blood products), so that vapors are not released into the atmosphere.

[0151] The present application is not limited to the described embodiments, but can vary in structure and details.

Claims

1. A gas trapping apparatus for medical fluids, the apparatus comprising: a bubble entrapment chamber (101); an inlet section (103) to the chamber having a plurality of entry ports (104, 105) which merge at an accumulation space in the chamber, the inlet section being adapted to allow mixing of fluid as it enters the chamber (101) via the plurality of entry ports; an outlet section to the chamber having at least one exit port (110); a drain tube having an intake end and an output end, the intake end being located within the chamber and the output end being connected to the at least one exit port; a diverter (102) in the chamber arranged to divert fluid from the inlet section (103) to have a transverse directional component relative to a longitudinal direction of entry into the chamber from the inlet section and to divert the fluid away from the at least one exit port and towards an inner surface of the chamber, wherein the diverter is shaped to divert the fluid away from the inlet section and radially towards the inner surface of the chamber before the fluid flows over the diverter and moves radially inwards towards the intake end; an inflow tube between the accumulation space and the diverter; and a diffuser comprising an aperture (107) around the inflow tube to cause fluid from the inlet section to have a transverse directional component via the aperture.

2. The apparatus of claim 1, wherein, The plurality of entry ports includes a dedicated vent port (306).

3. The apparatus of claim 1 or 2, wherein, The inlet section includes a turbulence inducing flow barrier (120).

4. The apparatus of claim 1 or 2, wherein, At least one entry port includes a turbulence inducing flow barrier (120).

5. The apparatus of claim 1 or 2, wherein, The chamber includes a hydrophilic membrane (603).

6. The apparatus of claim 5, wherein, The hydrophilic membrane (603) is mounted at a distal end of the diverter.

7. The apparatus of claim 1 or 2, wherein, At least one entry port includes a valve (705) for fully or partially closing the at least one entry port.

8. The apparatus of claim 1 or 2, wherein, Each of the plurality of entry ports includes a valve, and the apparatus includes a mechanism for interconnection of the valves and for their synchronous operation.

9. The apparatus of claim 1 or 2, wherein, The inlet section includes a single valve (906) mounted for alternately opening and closing the plurality of entry ports.

10. The apparatus of claim 1 or 2, further comprising a membrane that is selectively sealable at any one of the plurality of entry ports and the at least one exit port to maintain closed system integrity when connecting an external device to the any one port to transfer liquid or gas into or out of the chamber.

11. The apparatus of claim 1 or 2, wherein, The inlet section includes a common conduit for the plurality of entry ports.

12. The apparatus of claim 11, wherein, The common conduit extends parallel to the longitudinal direction.

13. The apparatus of claim 1 or 2, wherein, The apparatus includes a holder (811) for attachment to a support as part of an infusion set-up.

14. The apparatus of claim 1, wherein, The apparatus includes a sealable vent port (920).

15. The apparatus of claim 14, wherein, The vent port includes a vent opening (2110) and an end cap (2101) engageable with the vent opening.

16. The apparatus of claim 15, wherein, The end cap and vent opening have interengaging features that are engageable by pushing the end cap into the vent opening.

17. The apparatus of claim 15, wherein, The end cap and vent opening include interengaging ridges (2105) and grooves (2104).

18. The apparatus of claim 15, wherein, The end cap has a curved exposed surface without a handgrip.

19. The apparatus of claim 15, wherein, The end cap is linked to the vent opening by a strap member (2530).

20. The apparatus of claim 19, wherein, The band member has a ring that engages around the vent opening to allow rotation of the ring around an axis of the vent opening.

21. The apparatus of any one of claims 15 to 20, wherein, The end cap is configured to be closed only without removal.

22. The apparatus of claim 15, wherein, The end cap and the vent opening have interengaging features (2606, 2612) to provide a snap-fit lock that pushes the end cap into the vent opening.

23. The apparatus of claim 1 or 2, wherein, The diameter of each of the plurality of access ports (104, 105) is in the range of 1.5 mm to 8.0 mm, and the distance between the upper end of the collection space and the aperture (107) is no more than 20 mm.

24. An infusion apparatus comprising a gas trap apparatus as claimed in any of the preceding claims, and an infusion line linked to the inlet portion and an infusion line linked to the outlet portion.

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