Arrangement in the form of a speaking valve for placement and attachment to a tracheostomy tube

Description

Technical area

[0001] The invention relates to a speaking valve arrangement for placing and attaching to a tracheostomy cannula, with a flow body enclosing a flow channel, which has a flow body wall that radially encloses the flow channel, and which has a suitably designed connecting structure on one end for joining to a proximal end of the tracheostomy cannula, at the end of which a one-way valve is arranged opposite the connecting structure along the flow channel, and which provides a valve opening that can be closed by a pressure relief valve arrangement between the connecting structure and the one-way valve.

[0002] Tracheostomy tubes provide direct access to a person's trachea, bypassing the mouth, throat, and larynx, for the purpose of direct air flow to and from the lungs. In addition to so-called unblocked tracheostomy tubes, which are primarily used in spontaneously breathing patients with constant, reflexive, and aspiration-free swallowing, so-called blocked tracheostomy tubes, which have a dilatable cuff on the distal side, are used for invasive ventilation and / or the ventilation of patients at risk of aspiration. It is important to ensure that uncontrolled escape of respiratory gases through the throat and mouth during ventilation is avoided. Furthermore, it is important to prevent food residue or saliva from entering the lower airways or lungs, particularly in patients with swallowing difficulties.

[0003] The open, proximal end of a tracheostomy tube has a suitably designed connection flange for attaching, for example, a ventilator, a tube extension or for the attachment of a flow body that warms and humidifies the inhaled air, HME (Heat and Moisture Exchanger) for short, or a so-called speaking valve.

[0004] A speaking valve enables speaking, provided the vocal cords and upper airways are intact and functioning. A speaking valve is a one-way valve designed to open upon inhalation, directing airflow through the tracheostomy tube into the lungs. It closes upon exhalation, allowing exhaled air to pass through the larynx and over the vocal cords, where it stimulates sound. However, this requires the tracheostomy tube to be unblocked. This requires the cuff at the distal end of the tracheostomy tube to be deflated, allowing a sufficiently large gap to form between the cuff and the trachea.

[0005] Alternatively or in combination with the unblocked tracheostomy tube, so-called sieved or fenestrated tracheostomy tubes support the overflow of exhaled air over the vocal cords during exhalation when using a speaking valve.

[0006] However, a problem arises when using a speaking valve with a non-fenestrated tracheostomy tube if the cuff is accidentally left deflated, meaning the tracheostomy tube is blocked, preventing the patient's exhaled air from escaping. In this case, the speaking valve allows inspiration but not exhalation. Within a few breaths, the lungs are maximally overinflated. The patient is at risk of suffocation because they can no longer breathe, and there is also an acute risk of the lung bursting (pneumothorax), for example, due to excessive pressure when coughing.

[0007] A similar situation can occasionally occur with an unblocked tracheostomy tube if the mucous membrane around the tracheostomy tube swells unexpectedly, thereby narrowing the lumen between the trachea and the tracheostomy tube.

[0008] To counteract these risks, which a patient is particularly exposed to when a speaking valve is directly attached to a blocked and neither fenestrated nor screened tracheostomy cannula, the document WO 2016 / 139441 A1 proposes arranging a pressure relief valve in the area of the speaking valve attachment between the connection to the tracheostomy cannula and the one-way valve of the speaking valve attachment, the valve function of which is set in such a way that the pressure relief valve closes fluid-tight or gas-tight when pressure conditions within the speaking valve arrangement are harmless to the patient and can only trigger spontaneously when a predetermined overpressure within the speaking valve arrangement is exceeded, thereby releasing a valve opening through which excess exhaled air can flow into the environment largely without resistance.

[0009] The well-known pressure relief valve is designed in the form of a ball valve, which, due to the inherent weight of the ball, is able to seal a valve opening gas-tight. The size, weight, and arrangement of the ball are designed such that, in the event of an overpressure situation that is dangerous for the patient, the ball is lifted against gravity, thereby opening the vent opening.

[0010] The speaking valve for tracheostomy tubes described in EP 2 908 895 B1 also has, in addition to the one-way valve function characteristic of speaking valves, the option of venting by manually moving an opening mechanism into an open position, allowing free breathing, as is the case with a tracheostomy tube without an attached speaking valve. Opening requires active, targeted action by the patient, which cannot necessarily be assumed for patients receiving intensive care.

[0011] EP 2 326 376 B1 discloses a combined valve assembly for attachment to a tracheostomy tube. It has an inspiratory valve and a separate expiratory valve for the purposes of artificial or mechanical ventilation. The latter is designed as an adjustable PEEP (positive end-expiratory pressure) valve. Specifically, the expiratory PEEP valve is a ball-and-cage valve with a spring whose tension can be used to adjust the airflow resistance of the expiratory PEEP valve.

[0012] EP 0 617 630 B1 discloses a tracheostomy valve comprising a combined inspiratory and expiratory valve, both of which are designed as flat closing elements mounted on one side and pivotable bidirectionally about an axis. Both closing elements overlap each other to completely close the tracheostomy valve and, depending on the air pressure conditions within the valve, to partially or completely open the air flow path.

[0013] EP 0078685 A1 describes an arrangement with a valve for controlling the airflow through the tracheostoma as a function of the respiratory airflow pressure, as well as a device for releasably attaching the valve to the stoma. The valve has a flexible membrane movable between a first, a second, and a third position. The first position is used for normal breathing through the valve. The flexible membrane is moved by vocal exhalation to the second position, in which it engages the valve seat, thereby interrupting the airflow through the valve. The flexible membrane is moved to the third position by the pressure generated in the trachea during coughing, allowing airflow through the valve.

[0014] US 2014 / 0305440 A1 discloses a ventilation valve connected to a tracheostomy tube and comprising a tubular valve body, to the proximal end of which a perforated disc endpiece with an O-ring around its circumference is removably inserted. A floppy membrane overlying the inside of the disc endpiece serves as an inlet valve to allow the patient to inhale and take in air, and as a check valve to block the patient's exhalation, directing it to the larynx, sinuses, and mouth for normal speech. The O-ring yields upon forceful patient exhalation to release the disc endpiece from the tubular valve body. The ventilation valve itself is also attached to the tracheostomy tube to prevent it from slipping out of place after the connection is severed.The inhalation valve also has a whistle that produces an audible signal when the exhalation is forceful.

[0015] The document US 5,765,560 A discloses a tracheostome valve with a flow body enclosing a flow channel, one end of which can be connected to a tracheostomy cannula and at the other end of which a tilt valve arrangement is attached. The tilt valve arrangement consists of two surface elements of different surface sizes, each pivoted about a rotation axis. The smaller surface element serves as a one-way valve and, when open, ensures inspiration through a breathing opening provided in the larger surface element. When closed, it allows the respiratory air flow to overflow the vocal cords, with the smaller surface element covering the breathing opening provided in the larger surface element. In the event of excess pressure occurring, both surface elements pivot together into a position that opens the tracheostome valve to its maximum.

[0016] Despite the commercially available speaking valves, as well as the knowledge and informal advice to only attach speaking valve attachments to unblocked tracheostomy tubes, deaths continue to occur worldwide due to the attachment of a speaking valve attachment to a blocked tracheostomy tube, even when the tube is placed by experienced surgeons or caregivers. Consequently, in July 2019, the Federal Institute for Drugs and Medical Devices (BfD) pointed out this usability deficiency and required clear warnings on speaking valve attachments. Even the use of pressure relief valves designed as ball valves in the area of the speaking valve assembly cannot rule out functional malfunctions due to their spatial position sensitivity. Description of the invention

[0017] The invention is based on the object of developing a speaking valve arrangement for placing and attaching to a tracheostomy cannula, with a flow body enclosing a flow channel, which has a flow body wall that radially encloses the flow channel, and which has a suitably designed connecting structure on one end for joining to a proximal end of the tracheostomy cannula, at the end of which a one-way valve is arranged opposite the connecting structure along the flow channel and provides an opening that can be closed by a pressure relief valve arrangement between the connecting structure and the one-way valve, in such a way that the previously existing risk to the patient when placing a speaking valve on or against the tracheostomy cannula can be avoided or significantly reduced.For example, a speaking valve as described above is intended to ensure that spontaneously developing overpressure in a patient's airway, e.g., due to coughing, is safely and immediately relieved, regardless of the direction of gravity. Alternatively, or in combination with the above precaution, the speaking valve arrangement must be modified or supplemented so that, if a life-threatening overpressure situation occurs that leads to at least a partial opening of an existing pressure relief valve arrangement, a person in charge of the speaking valve arrangement is alerted to the otherwise life-threatening situation for the patient.

[0018] The solution to the problem underlying the invention is specified in claim 1. Features that advantageously further develop the inventive concept are the subject of the subclaims and the further description, in particular with reference to the exemplary embodiments.

[0019] According to the solution, a speaking valve arrangement for placing and attaching to a tracheostomy cannula with the features of the preamble of claim 1 is designed such that the valve opening completely penetrates the flow-through body wall, and that the pressure relief valve arrangement has at least one elastically deformable valve flap which, in a first state - in which pressure conditions prevail within the speaking valve such as are usual when speaking - is able to cover the valve opening provided between the connecting structure and the one-way valve on the flow-through body and, in the event of a predeterminable excess pressure within the flow-through channel, can be converted into a second state in which the valve opening is at least partially exposed by an excess pressure-driven elastic deformation of the valve flap - in which excess pressure conditions prevail, such as those which occur, for example, when coughing.

[0020] The design and functional principle of the pressure relief valve assembly attached to the flow body of the speaking valve is inspired by a naturally occurring opening mechanism on a carnivorous plant called a "water hose" ( Utricularia vulgaris / Utricularia australis) used suction trap. The suction trap is a trap bladder that can be closed with a flexible flap and is able to transport liquid in the form of water from the interior of the bladder into the environment via glands, causing the bladder walls to bulge inwards, developing an elastic wall tension. The trap entrance is sealed watertight by a trapdoor that, in this state, bulges outwards and whose free edge rests against a tissue sill. In this state, the pressure inside the trap is negative compared to the ambient pressure. Upon contact with prey, the trapdoor reverses its convex curvature into a concave shape within less than 2 ms, thereby at least partially exposing the trap entrance.In this unlocked suction trap state, a negative pressure-driven pressure equalization occurs, whereby the suction trap walls relax and water and prey flow into the interior of the suction trap immediately in front of the suction trap opening due to the volume increase that occurs within a millisecond.

[0021] The functionality explained above makes use of the pressure relief valve arrangement integrated in the arrangement within a speaking valve in an abstract manner (reverse with regard to the pressure conditions) in that the at least one elastically deformable valve flap, similar to the trap door in the biological model, assumes the second state which at least partially releases the valve opening when there is a sudden pressure difference between the interior of the flow-through body, ie the speaking valve arrangement, and the ambient pressure, which usually corresponds to the currently prevailing air pressure, whereby the excess pressure is reduced instantly.

[0022] In order not to impair the functionality of the speaking valve in the speaking range, the overpressure-dependent opening of the pressure relief valve arrangement, which is achieved by a largely delay-free transfer of the at least one elastically deformable valve flap from the first to the second state, is to be initiated from an adjustable pressure difference, e.g. from 35 to 45 cm H2O, i.e. 0.034 bar to 0.044 bar. In the pressure range below the above trigger pressure for the pressure relief valve arrangement, i.e. for pressures in the speaking range between 0 to 25 cm H2O, i.e. 0 to 0.0245 bar, the at least one elastically deformable valve flap remains in the first, i.e. closed, state, so that a sufficiently pressurized air flow during normal operation of the speaking valve can stimulate the patient's own vocal cords to speak.The actual pressure ranges to be applied and the maximum opening area of the valve flap can be realized differently depending on the patient's muscle strength, size and lung volume, preferably by selecting a lower overpressure range and a smaller maximum opening area for weak or small patients with low lung volume than for strong or large patients with high lung volume.

[0023] In contrast to a known ball valve arrangement, the functioning of which depends on the inherent weight of the ball and thus on the spatial arrangement and position of the entire ball valve, the inherent weight of the at least one elastically deformable valve flap plays no or no significant role in the functioning of the pressure relief valve arrangement according to the solution, whereby the functioning of the arrangement according to the solution within the speaking valve is guaranteed in every spatial arrangement and position.

[0024] The flow-through body has a flow-through channel wall that radially surrounds the flow channel and is locally penetrated by the valve opening of the pressure relief valve arrangement. The valve opening is arranged at a distance along the flow channel, preferably centrally, between the connecting structure and the one-way valve. An opening normal can be assigned to the valve opening, which is oriented orthogonally to the longitudinal axis of the flow channel, i.e., the valve opening is oriented facing the longitudinal axis.

[0025] In a preferred embodiment, a single elastically deformable, flat valve flap is provided which covers the valve opening in the first state, wherein the elastically deformable valve flap is joined directly or indirectly to the flow-through body relative to the valve opening such that the elastically deformable valve flap is arranged facing the flow channel and away from the valve opening. In an alternative embodiment, the valve flap is arranged outside the flow-through body and closes the back of the valve opening in the first state. This ensures that in the event of damage, the valve flap or even parts of it cannot enter the patient's airway. In addition, this opens up the possibility of safely and quickly replacing the valve flap in the form of a replacement module without having to open the interior of the speaking valve.

[0026] In all possible embodiments, two half-spaces can be assigned to the valve opening, of which in one of the two half-spaces the elastically deformable valve flap is joined at least partially in a fixed position relative to the valve opening and within the other of the two half-spaces the elastically deformable valve flap is loosely mounted to the valve opening. In a figurative sense, the joining of the elastically deformable valve flap relative to the valve opening corresponds to the attachment of a swing door that is rotatable on one side of a door frame. In contrast to the attachment and design of a swing door known per se, the at least one elastically deformable valve flap in the first state covers the valve opening within its second half-space at least partially with an edge-side excess, i.e. the elastically deformable valve flap extends at least partially beyond a region of the valve opening edge.This marginal oversize contributes to the elastically deformable valve flap remaining in the first state, i.e. in the state closing the valve opening, when the speaking valve is in operation, as long as the pressure prevailing within the speaking valve arrangement remains below the specified overpressure range.

[0027] In addition to the dimensioning of the oversize, a multitude of other material and design parameters play an important role in adjusting the overpressure-driven opening function of the novel pressure relief valve arrangement. As explained below with reference to illustrated exemplary embodiments, the shape, size, and material selection for the formation of the at least one elastically deformable valve flap, as well as the geometry of the edge-side valve opening contour, contribute to the safe and reliable function of the pressure relief valve arrangement.

[0028] Preferably, the edge-side oversize is not uniformly dimensioned, but has a minimum at at least one location. In this way, the opening process can be determined by the overpressure-driven elastic deformation of the at least one valve flap in a geometrically predetermined manner, in which the at least one valve flap realizes an elastic transformation from the first to the second state most quickly in time.

[0029] Due to the typically cylindrical design of the flow-through body of known speaking valve attachments on tracheostomy cannulas, it is advisable to form the valve opening, preferably centrally, spaced between the connecting structure and the one-way valve by a rectangular or slot-shaped recess within the flow-through body wall or by a valve opening which adjoins the rectangular or slot-shaped recess within the flow-through body wall and whose larger opening dimension is arranged in the circumferential direction around the flow channel and whose smaller opening dimension is arranged parallel to the flow channel.

[0030] In this case, the at least one elastically deformable valve flap is designed to be flat and has a flat, curved shape adapted to cover the valve opening.

[0031] In order to take into account the aforementioned aspect of different speaking pressures in patients of different constitutions, the at least one elastically deformable valve flap can be exchangeably attached directly or indirectly to the flow-through body of the arrangement in the manner of a speaking valve. In one embodiment, two fastening pins are used to detachably and firmly attach the elastically deformable valve flap on one side, to which the valve flap can be plugged, forming a flat, curved three-dimensional shape. In this case, the two fastening pins are attached in the area of the pressure relief valve arrangement facing the flow channel. In an alternative embodiment, the pressure relief valve arrangement adjoins the flow-through body in the area of the valve opening and provides a slot-shaped insertion opening into which the valve flap can be inserted in the form of a plug-in module.In this version, the valve flap can be replaced from the outside for hygiene reasons without having to open the speaking valve. To do this, a retainer that releasably secures the valve flap is removed, which can then be pulled out of the slotted insertion opening and replaced with a new one. The retainer and the standard particle filter foam element in the speaking valve prevent the valve flap from accidentally slipping off and being inhaled.

[0032] By stocking a number of valve flaps that differ from one another at least in their shape, size, or elastic properties, a patient-specific selection can be made to adjust the trigger pressure of the pressure relief valve assembly to the specific patient. Further details can be found in the following description with reference to an illustrated embodiment.

[0033] Alternatively or in combination with the design of the above-described safe and position-independent opening pressure relief valve arrangement, the risk to the patient's life resulting from incorrect operation of a speaking valve arrangement can be avoided or significantly reduced by arranging a signal generating means directly or indirectly on the pressure relief valve arrangement or downstream of it, however the pressure relief valve arrangement may be designed, which generates a signal in the event of an overpressure-driven opening of the pressure relief valve arrangement, ie in the overpressure range.

[0034] Preferably, the signal generating means is designed to generate an acoustically perceptible sound signal that can be clearly perceived by a person handling the speaking valve assembly in the form of an alarm signal. The alarm signal alerts the person to any possible error, allowing the blocked tracheostomy tube to be corrected immediately.

[0035] Simultaneously with the signal generation, a spontaneous pressure relief occurs through the opened pressure relief valve arrangement, thus preventing the risk of immediate suffocation and bursting of the patient's lung. The person handling the speaking valve attachment is thus given time to correct the operating error. By combining signal generation with the pressure relief function, preferably based on the above-described, solution-based pressure relief valve arrangement, on the one hand, the uninterrupted function of the speaking valve during normal use, i.e. at the pressures prevailing during normal breathing and speaking (speech range), is ensured without false alarms, and on the other hand, when a predetermined overpressure range is exceeded within the speaking valve attachment, both a signal is triggered and immediate pressure relief is implemented simultaneously to protect the patient. Reduces after triggering, i.e.When the pressure relief valve arrangement is opened, the pressure prevailing in the flow body, e.g. due to inhalation, the elastic valve flap swings back to its original position and closes the valve opening automatically, so that the speaking valve can continue to be used in the usual way.

[0036] In a preferred embodiment, the signal generating means is designed in the form of a whistle and is located within a flow channel downstream of the pressure relief valve arrangement. Depending on the design and arrangement of the whistle, it is advisable to locally structure the flow channel to form a labial or lingual whistle.

[0037] Alternatively, or in combination, the signal generating means can generate an electrical, electromagnetic, or optical signal, which is either emitted in the immediate vicinity for physiological perception by a person or transmitted via cable or wirelessly to a monitoring unit, for example, in the form of a central monitoring unit. For this purpose, a sensor that detects the overpressure situation must be arranged in or on the pressure relief valve arrangement. The sensor signals can be fed to a central monitoring unit to trigger an alarm or transformed into a physiologically perceptible form. The sensor can be combined with the valve mechanism or implemented as an independent signal generator. Brief description of the invention

[0038] The invention is described below, without limiting the general inventive concept, using exemplary embodiments with reference to the drawings. They show: Fig. 1 perspective longitudinal section through a first arrangement designed according to the solution in the manner of a speaking valve, Fig. 2a-f cross-sectional view of the first arrangement of a pressure relief valve arrangement according to the solution as sequence images, Fig. 3a-j perspective longitudinal section through a first arrangement designed according to the solution in the manner of a speaking valve as sequence images Fig. 4 perspective cross-sectional view through the first arrangement designed according to the solution in the manner of a speaking valve, Fig. 5 perspective longitudinal section through a second arrangement designed according to the solution in the manner of a speaking valve, Fig. 690° to Fig. 5twisted perspective longitudinal sectional view through the second arrangement designed according to the solution in the manner of a speaking valve, Fig. 7perspective oblique view of the second arrangement designed according to the solution in the manner of a speaking valve without a one-way valve, and Fig. 8a-fperspective longitudinal sectional images through the pressure relief valve arrangement of the second arrangement designed according to the solution in the manner of a speaking valve in the form of sequential images. Ways of implementing the invention, industrial applicability

[0039] Figure 1 shows a perspective longitudinal section through a speaking valve arrangement, which has a hollow cylindrical flow body 1, at the upper, in Figure 1For better illustration purposes, a one-way diaphragm flap valve, not further known per se, is arranged at the flow-through body end 2, which is designed to be open, which opens the upper flow-through body end for an inspiratory air inflow 3 and prevents a respiratory air outflow 3'.

[0040] At the Figure 1Adjoining the lower end 4 of the flow-through body is a connecting structure 5, via which the speaking valve arrangement can be joined, preferably removably and fluid-tight, to a tracheostomy cannula 6. At the transition between the flow-through body 1 and the connecting structure 5, which in the illustrated embodiment has a smaller inner diameter than the flow-through body 1, a grid structure 7 is arranged, which, on the one hand, has a protective function against the uncontrolled entry of foreign particles in the direction of the tracheostomy cannula 6 and, on the other hand, offers a mechanically stable support plane for a standard particle filter foam element (not shown).

[0041] In addition, the arrangement in the manner of a speaking valve within the flow-through body 1, whose flow-through body wall 8 comprises a flow channel 9, provides an opening 10 which completely penetrates the flow-through body wall 8 and is arranged between the upper flow-through body end 2 and the lower flow-through body end 4.

[0042] At the opening 10 there is a pressure relief valve arrangement 11, the structure and operation of which can be described with reference to the Figures 2 and 3 which will be explained in more detail below using the sequence images shown.

[0043] The sequence images of the Figures 2a to f represent longitudinal sections through the pressure relief valve arrangement 11 arranged at the opening 10 within the flow-through body wall 8 of the flow-through body 1. The flow-through body wall 8 radially encompasses the flow channel 9. The Figures 3a to jThe sequence images shown represent perspective longitudinal sections through the entire arrangement in the form of a speaking valve. All Figures 2 and 3 The sequence images illustrated are able to clearly characterize the functioning and the dynamic deformation behavior of the elastically deformable valve flap 15 which determines the pressure relief valve function.

[0044] The pressure relief valve assembly 11 is fluid-tightly connected to the opening 10 within the flow-through body wall 8 directly radially outside the flow-through body 1. The pressure relief valve assembly 11 can be designed as a separate structural unit from the flow-through body 1, as shown, or can be integrally connected thereto. The pressure relief valve assembly 11 has a valve opening 12, which in the illustrated case is smaller than the opening 10 extending through the flow-through body wall 8. However, variants of the pressure relief valve assembly 11 in which the opening 10 and the valve opening 12 are identical are also conceivable.

[0045] The pressure relief valve arrangement 11 has a flow channel wall 13 comprising a flow channel 14, which opens into the environment via at least one opening 13', see. Fig. 1 . Thus, ambient pressure conditions prevail within the flow channel 14.

[0046] The valve opening 12 is in a first state, see Figure 2a , 3a completely covered by an elastically deformable valve flap 15. The valve flap 15 is designed as a membrane or film and is made, for example, of an elastomer. Two fastening pins 16 are used to attach the valve flap 15 within the pressure relief valve arrangement 11, which are attached to the pressure relief valve arrangement 11 in a radial projection onto the opening 10 within the opening area of the opening 10, see in particular the illustration according to Figure 3a to j. The elastically deformable valve flap 15 has holes corresponding to the fastening pins 16, so that the valve flap 15 is removably and firmly joined to the pressure relief valve arrangement 11 along its upper valve flap edge.

[0047] The shape and size of the elastically deformable valve flap 15 are adapted to the shape and size of the valve opening 12 in such a way that it projects axially beyond the valve opening 12 on both sides with an excess, whereas the extension of the valve flap 15 in the circumferential direction corresponds at most to the valve opening width w of the valve opening 12, see. Figure 3c . The joining of the elastically deformable valve flap 15 to the pressure relief valve arrangement 11 also allows for an uncomplicated replacement of the valve flap 15.

[0048] In an unjoined state, the elastically deformable valve flap 15 has a flat, rectangular shape. After joining the valve flap 15 into the pressure relief valve assembly 11 using the fastening pins 16, the valve flap 15 is converted into a flat, bent shape, correspondingly adapted to the cylindrical curvature of the flow-through body wall 8, whereby the elastically deformable valve flap 15 acquires dimensional stability determined by the bend, its size, shape, and the inherent elasticity of the valve flap material.

[0049] The lower valve flap edge 17 of the valve flap 15, which is axially opposite the fastening pins 16, projects axially beyond the lower edge delimiting the valve opening 12, which is designed like a threshold, see Figures 2ato f. The threshold-like design of the lower valve opening edge 18 provides an axially oriented flank facing the valve flap 15 in the first state, against which the lower valve flap edge 17 rests flush with an oversize. In the direction of the inner flow channel 14 of the pressure relief valve arrangement 11, a continuously sloping threshold flank 19 adjoins, the function of which will be explained below. In addition, the threshold-shaped lower valve opening edge 18 has a varying threshold height h in the circumferential direction of the pressure relief valve arrangement 11 such that the threshold height h is maximum at both valve opening edges opposite each other in the circumferential direction and minimum in the center, see Figures 2d , 3e,f. In this way, the elastically deformable valve flap 15 overlaps the valve opening 12 with a maximum excess at its edge regions and with a minimum excess in the central region of the valve flap 15.

[0050] The shape, size, thickness, and elastomer material of the elastically deformable valve flap 15 determine the elastic deformation behavior of the valve flap and thus establish the minimum overpressure required to open the pressure relief valve assembly. By providing a number of differently configured valve flaps, which differ from one another in their elastic deformation behavior, the arrangement according to the solution, similar to a speaking valve, can be individually adapted to the respiratory physiological capabilities or characteristics of a patient.

[0051] In the following, the sequence images of both the Figures 2 and 3referred to together in order to explain in more detail the transfer of the elastically deformable valve flap 15 from the first state in which the pressure relief valve arrangement 11 is closed, to the second state in which the pressure relief valve arrangement 11 assumes an open position.

[0052] The Figures 2a , 3b show the pressure relief valve arrangement 11 in the first state, ie the valve flap 15 closes the valve opening 12 largely gas-tight and ensures that pressure conditions can develop within the flow body 1, which enable the patient to speak.

[0053] If the pressure within the flow body 1 increases, for example due to spontaneous coughing, the elastically deformable valve flap 15 is deformed by overpressure, see Figure 2b , 3b. If there is a sufficiently high overpressure Ü acting on the valve flap 15 from the inside, i.e. from the side of the flow channel 9, the valve flap 15 is deformed radially outwards by the pressure event, primarily in the central region, so that the lower freely movable valve flap edge 17 passes over the lower threshold-like valve opening edge 18, which is lowered centrally compared to the edge regions. At this opening moment of the pressure relief valve arrangement 11, a central vertical fold forms on the lower valve flap edge 17 due to the threshold-like geometry along the lower valve opening edge 18, see Figure 3c , whereby the valve flap 15 deforms abruptly or abruptly from its center radially outwards into the volume of the pressure relief valve arrangement 11, see Figure 3d , 2c. At this moment, both a temporary stiffening of the valve flap 15 in its center and a structural instability of the surface of the valve flap 15 occur due to the elimination of its surface curvature over the entire valve flap 15. Subsequently, the valve flap 15 is displaced by overpressure from its center into the lumen or flow channel 14 of the pressure relief valve arrangement 11, with the peripheral areas of the valve flap being pulled along by the lower valve opening edge 18. The valve opening 12 is released, see the Figures 2c, 2d or 3e, f, wherein the overpressure Ü suddenly formed within the flow body 1 is effectively reduced by an air flow L directed through the valve opening 12.

[0054] By reducing the excess pressure or completely equalizing the pressure, the elastically deformable valve flap returns to its original position due to its inherent elasticity, see Figure 2e , 3gand comes with its lower valve flap edge 17 to rest on the inclined threshold flank 19 of the lower valve opening edge 18, see Figure 2e If there is no further pressure surge triggered by coughing, the valve flap 15 is returned to the first state, in which the valve flap 15 completely covers the valve opening 12, if necessary supported by a negative pressure U developing within the flow body 1 due to inhalation, see Figure 2f , 3j .

[0055] In a preferred embodiment, as shown in the sequence image representations according to Figure 2a to fAs shown, the lower valve flap edge 17 opens into a groove-shaped recess 20, which, in addition to the inherent stability of the valve flap 15 due to the curvature in the first state, limits the movement of the valve flap 15. The curved shape of the valve flap 15, which is caused by the cylindrical or round shape of the flow-through body, as well as a particle filter foam element (not shown) resting on the grid structure 7 and the joining of the valve cap 15 within the groove-shaped recess 20 prevent the valve flap 15 from piercing or being sucked into the interior of the speaking valve arrangement.

[0056] The valve flap principle, borrowed from the field of biology and explained at the beginning, is based exclusively on an isotropic pressure difference between the interior of the flow body 1 and the environment. Thus, the functionality of the "bionic-inspired" pressure relief valve arrangement 11 is position-independent.

[0057] In a preferred development of the arrangement in the manner of a speaking valve, to counteract the risk of a life-threatening situation for the patient due to improper handling of the tracheostomy cannula, a signal generating means 21 for generating an acoustically perceptible sound signal, preferably in the form of a whistle 22, is arranged downstream of the pressure relief valve arrangement 11, see Figure 3 as well as Figure 4 . In Figure 4The flow body 1 including the pressure relief valve arrangement 11 is shown in a cross-section. Downstream of the opening 10 or valve opening 12 there is a flow channel 14, which in the case of the Figure 4 In the embodiment shown, it is oriented in the circumferential direction of the flow-through body 1. A whistle 21, preferably in the form of a labial whistle contour, is arranged along the flow-through channel 12. If an overpressure situation arises that endangers the patient, the pressure relief valve arrangement 11 is suddenly opened, for example in the manner described above, whereby an escape of the overpressure-driven air flow through the pressure relief valve arrangement 11 in the area of the whistle 22 generates an acoustically perceptible signal tone that alarms those around the patient, so that a person caring for the patient is immediately alerted to the dangerous situation and can take appropriate countermeasures.

[0058] Not necessarily, however, in an advantageous form, the signal generating means 21 is provided with the bionic pressure relief valve explained above in the Figure 4 removable manner. Similarly, known pressure relief valve arrangements, for example in the form of a ball valve, can be provided with a corresponding signal generating means, preferably in the form of a whistle, in the region of the air outlet opening.

[0059] It is also conceivable to design the signal generating means to generate an electrical, electromagnetic, or optical signal, which can optionally be transmitted to a central monitoring unit either by cable or wirelessly. For this purpose, sensor systems known per se are available to the person skilled in the art, with which, for example, a deflection of the elastically deformable valve cap and / or an air flow within the flow channel can be detected.

[0060] Figure 5shows a second embodiment of a speaking valve arrangement according to the solution, which, like the one in Figure 1 in a perspective longitudinal section. To avoid repetition, the reference numerals already explained and used below correspond to those components described above, the function of which will not be explained again. In addition to Figure 1 is in Figure 5 , which has a known one-way diaphragm flap valve arranged at the upper, open end 2 of the flow body, which opens the upper end 2 of the flow body for an inspiratory air inflow 3 and prevents it for a respiratory air outflow 3'.

[0061] In addition, the arrangement in the manner of a speaking valve provides within the flow-through body 1, the flow-through body wall 8 of which comprises a flow-through channel 9, an opening 10 which completely penetrates the flow-through body wall 8 and is arranged between the upper flow-through body end 2 and the lower flow-through body end 4, ie the opening 10 is arranged along the flow-through channel 9 at a distance from the upper and lower flow-through body ends 2, 4 and is oriented towards the flow-through channel 9 transversely to its longitudinal extent 24.

[0062] At the opening 10, outside the flow body wall 8, a pressure relief valve arrangement 11 is connected, the structure and functioning of which is basically the same as in the Figures 1 to 4 illustrated pressure relief valve arrangement 11. However, in contrast to this, the valve flap 15 ( Figure 5) not facing the flow channel 9 and detachably attached to two fastening pins 16, as can be seen from Fig. 2 A to F as well as Fig. 3 A to Jvisible, rather, the valve flap 15 is in the form of a plug-in module that can be inserted into a slot-shaped recess 25 within the flow channel wall 13 of the pressure relief valve arrangement 11 and can be fixed to the outside of the flow-through body wall 8 by means of a holder 26. In this way, in the first state, in which pressure conditions develop within the flow-through body 1 that enable the patient to speak, the valve flap 15 is able to cover or close the valve opening 12 of the pressure relief valve arrangement 11, which directly radially adjoins the opening 10 projecting through the flow-through body wall 8, from the side facing away from the flow-through channel. By attaching the valve flap 15 outside the flow-through body 1, it is impossible for the valve flap 15 to detach in an uncontrolled manner and enter the flow-through channel 9.

[0063] In addition, the pressure relief valve arrangement 11 provides curved guide walls 27 in the center and on the edge of the valve opening 12, to which the valve flap 15 clings in the first state and in this way assumes a defined valve flap curvature, which, as in the biological model, the trapdoor system of the suction trap of the water hose (genus Utricularia ) - as explained above - is convexly curved toward the side of the applied pressure, i.e., toward the speaking valve body. The radius of this curvature is determined by the louvre walls.

[0064] In the following, the sequence images A to F of the Figure 8 Reference is made to explain in more detail the transfer of the elastically deformable valve flap 15 from the first state in which the pressure relief valve arrangement 11 is closed, to the second state in which the pressure relief valve arrangement 11 assumes an open position, and back.

[0065] In idle mode, see Figure 8 A , the valve flap 15 rests on the guide walls 27. A threshold structure 28 is also provided at the lower edge of the valve opening 12. Lateral threshold structures 29 are attached to each of the two side walls that border the valve opening 12. During normal speech, the valve flap 15 is deflected from its rest position, see Figure 8 B , so that the lower edge of the valve flap 15, as in the biological model, rests against the inside of the lower threshold structure 28. To prevent leakage flow in this closed valve position, both side edges of the valve flap 15 rest tightly against the lateral threshold structures 29 from the inside.

[0066] In the event of a sudden pressure event within the speaking valve body, e.g. initiated by coughing, there is a change in the curvature of the valve flap 15, preferably in the middle of the flat valve flap 15, see Figure 8 C , whereupon the valve flap 15 passes over the threshold structures 28 and 29 and subsequently opens the valve opening 12 completely, see Figure 8 D .

[0067] During a subsequent inspiration by the patient, a negative pressure (U) is created inside the speaking valve, whereby the valve flap 15 seals at the rear of the threshold structures 28, 29, see Figure 8 E to return to their starting position, see Figure 8 F In order to ensure inspiration-driven resetting, the threshold structures 28, 29 are each flattened on the threshold side facing away from the valve flaps in the initial state.

[0068] Downstream of the pressure relief valve arrangement 11, as with the speaking valve arrangement according to the Figures 1 to 4In the illustrated embodiment, a signal generating means 21 for generating an acoustically perceptible sound signal, preferably in the form of a whistle 22, is arranged, so that reference is made to the above description for an explanation thereof. In the case of the above overpressure situation, in which the pressure relief valve arrangement 11 opens completely, see Figure 8 D , the pressure equalization-driven air flow passing through the flow channel 14 generates an unmistakable signal tone when passing the whistle 22.

[0069] The dynamic deflection behavior of the valve flap, both when the valve opens and when the open valve flap returns to the closed position, can be influenced by the pre-curvature of the valve flap as well as by the material and shape properties of the flat, elastic valve flap, such as the thickness, stiffness, and extensibility of the valve flap, which is preferably made of elastomer material. If stiffer or softer, or thicker or thinner valve flaps are used, the valve opens at a lower or higher pressure. Depending on the patient type (man / woman / child) and / or the patient's physiological constitution, a suitable valve flap must be inserted into the slot-like insertion opening provided for this purpose in the pressure relief valve assembly. The attending physician can use a range of differently configured valve flaps, which are designed and stocked as interchangeable insert modules. List of reference symbols

[0070] 1 Flow body 2 Flow body end 3 Inspiratory air inflow 3 Respiratory air outflow 4 Lower flow body end 5 Connecting structure 6 Tracheostomy tube 7 Grid structure 8 Flow body wall 9 Flow channel 10 Opening 11 Pressure relief valve arrangement 12 Valve opening 13 Flow channel wall 13 Flow channel opening 14 Flow channel 15 Valve flap 16 Fastening pin 17 Valve flap edge 18 Lower valve opening edge 19 Threshold flank 20 Groove-shaped recess 21 Signal generating means 22 Whistle 23 One-way flap valve arrangement 24 Longitudinal extension of the flow channel 25 Slot-shaped recess 26 Fastening element 27 28, 29 Threshold structures LAir flow ÜOverpressure UNegative pressure, inhalation

Claims

1. Speaking valve arrangement for fitting and attachment to a tracheostomy cannula (6), with a through-flow body (1) enclosing a through-flow channel (9), which has a through-flow body wall (8) that radially encloses the through-flow channel (9), and which has a suitably designed connecting structure (5) at one end for joining to a proximal end of the tracheostomy cannula (6), at the end of which structure, located opposite to the connecting structure (5) along the through-flow channel (9), is arranged a one-way valve (23), and a valve opening (10, 12) that can be closed by a pressure-relief valve arrangement (11) is arranged along the through-flow channel (9), spatially separated between the connecting structure (5) and the one-way valve (23), wherein the valve opening (10) passes completely through the through-flow body wall (8), and the pressure-relief valve arrangement (11) has at least one elastically deformable valve flap (15), which in a first state is able to cover the valve opening (10, 12) provided between the connecting structure (5) and the one-way valve (23) on the through-flow body (1), and in the event of a predefinable overpressure within the flow channel (9), can be converted into a second state, at least partially releasing the valve opening (10, 12) by an overpressure-driven elastic deformation of the valve flap (15).

2. Arrangement in accordance with Claim 1, wherein a signal generating means (21) is arranged directly or indirectly on the pressure-relief valve arrangement (11), or downstream of the pressure-relief valve arrangement (11), which in the event of an overpressure-driven opening of the pressure-relief valve arrangement (11) generates a signal.

3. Arrangement in accordance with Claim 2, wherein the signal generating means (21) is designed to generate an acoustically perceptible sound signal.

4. Arrangement in accordance with Claim 3, wherein the signal generating means (21) generates the sound signal by the vibrational excitation of an air flow passing through the pressure-relief valve arrangement.

5. Arrangement in accordance with Claim 3 or 4, wherein downstream of the valve opening (10, 12) that can be closed by the pressure-relief valve arrangement (11) is connected a flow channel (14), along which is arranged the signal generating means (21).

6. Arrangement in accordance with one of the Claims 3 to 5, wherein the signal generating means (21) is designed in the form of a whistle (22).

7. Arrangement in accordance with Claim 6, wherein the whistle (22) is designed in the form of a labial or lingual whistle.

8. Arrangement in accordance with one of the Claims 2 or 3, wherein the signal generating means (21) is capable of generating an electrical, electromagnetic or optical signal, and the signal generating means (21) is connected by cable or wirelessly to a monitoring unit, to which the signal can be transmitted.

9. Arrangement in accordance with one of the Claims 5 to 8, wherein the flow channel (14) is bounded by a flow channel wall (13), or by the through-flow body (1) and by a flow channel wall (13).

10. Arrangement in accordance with one of the Claims 1 to 9, wherein the at least one elastically deformable valve flap (15) has a shape and / or an inherent elasticity that develops a restoring force-based effect, by means of which the elastically deformable valve flap (15) can be at least partially translated from the second state into the first state.

11. Arrangement in accordance with one of the Claims 1 to 10, wherein two half-chambers can be assigned to the valve opening (10, 12), and the elastically deformable valve flap (15) is joined within one of the two half-chambers, at least in sections, in a fixed position relative to the valve opening (10, 12), and the elastically deformable valve flap (15) is mounted loosely relative to the valve opening (10, 12) in the other of the two half-chambers.

12. Arrangement in accordance with one of the Claims 1 to 11, wherein . the at least one elastically deformable valve flap (15) is interchangeably joined to the through-flow body (1) and / or to the pressure-relief valve arrangement (11) outside the through-flow body (1).

13. Arrangement in accordance with one of the Claims 1 to 12, wherein . at least two elastically deformable valve flaps (15) are provided, which differ from one another at least in shape, size. and / or in their elastic properties, of which at least one can be joined to the through-flow body (1) and / or to the pressure-relief valve arrangement (11). depending on the physiological properties of the patient in terms of breathing.

14. Arrangement in accordance with one of the Claims 11 to 13, wherein within the second half-chamber, the at least one elastically deformable valve flap (15) covers the valve opening (10, 12) in the first state, at least in sections, with an oversized edge, that is to say, the valve flap (15) extends, at least in sections, beyond the latter.

15. Arrangement in accordance with Claim 14, wherein the oversize of the edge is a minimum at at least one location.

16. Arrangement in accordance with one of the Claims 1 to 15, wherein the at least one elastically deformable valve flap (15) has a planar design, and in the first state has a surface normal, which forms at least an angle α with a longitudinal through-flow channel axis that can be assigned to the through-flow channel (9), for which the following applies: 80° ≤ α ≤ 100°.

17. Arrangement in accordance with one of the Claims 1 to 16, wherein in the first state the planar valve flap (15) has a convex surface curvature orientated towards the through-flow channel (9).