WO2003004082A1

WO2003004082A1 - Breathing valve for cpap units, valve body and method

Info

Publication number: WO2003004082A1
Application number: PCT/DE2002/001975
Authority: WO
Inventors: Martin Baecke
Original assignee: Seleon Gmbh
Priority date: 2001-05-31
Filing date: 2002-05-29
Publication date: 2003-01-16
Also published as: DE10126633A1; DE10126633B4

Abstract

The invention relates to a breathing valve for CPAP units, comprising an inlet (21), an outlet (18) and a breathing opening (22). A device (3, 11, 12, 16, 17, 18) is provided which prevents a significant proportion of the exhaled air from flowing through the inlet (21), in order to improve the hygiene of CPAP units.

Description

Breathing valve for CPAP devices, valve bodies and processes

This invention relates to a breathing valve for CPAP devices according to the preamble of claim 1, a valve body for such a breathing valve and a method for performing the CPAP therapy.

The CPAP (continuous positive airway pressure) therapy is in Chest. Volume No. 110, pages 1077-1088, October 1996 and Sleep, Volume No. 19, pages 184-188. It is intended to prevent obstructive breathing disorders. These lead to apneas (respiratory arrest), through which the sleeper awakens. Frequent apneas prevent the sleeper from falling into a restful deep sleep. People who suffer from apneas while sleeping are therefore not well rested during the day, which can lead to social problems at work and, in the worst case, fatal accidents, for example for professional drivers.

CPAP devices for carrying out CPAP therapy are known. A CPAP device uses a compressor or a turbine, preferably via a humidifier, a ventilation hose and a nasal mask, to apply a positive pressure of up to about 30 mbar in the patient's airways. This overpressure is intended to ensure that the upper airways remain fully open throughout the night and thus no apneas (respiratory arrests) occur (DE 198 49 571 A1).

Bi-PAP and multilevel devices are also known. These apply a lower pressure during exhalation than when inhaling.

Exhalation valves are used in CPAP therapy to direct the air exhaled by the patient during treatment. They are either located directly on the face mask or are attached as a component between the mask and the ventilation hose. Regardless of the individual design, these exhalation valves are only throttle valves: they only create unchangeable openings to the outside and thus represent a flow resistance for the air supplied by the compressor. The lower this flow resistance, the higher the air flow supplied by the compressor to apply a certain excess pressure in the patient's airways. Some manufacturers of devices for CPAP therapy with the corresponding names for their exhalation valves are listed below: MAP (DE): Aero-Click®; Mallinckrodt (USA): Breeze ™ SleepGear ™ Mask; active exhalation valve; Respironix (USA): Profile ™ Lite Mask, Spectrum® Reuseable Filling Face Mask; ResMed (AUS): Ultra Mirage ™ Mask, Mirage® Filling Face Mask with vacuum safety valve; MPV-Truma (DE): AirPilotMask®; Taema (FR): Concept 5 (mask system); Breas (SE): SleepNet IQ® Nasal Mask.

Although the production of these exhalation valves is very inexpensive, there are necessarily disadvantages. A constant flow of air to the outside forces the ventilator to provide large amounts of air. The compressors / turbines in the devices are designed to be correspondingly powerful. The openings in the exhalation valves, on the other hand, are far from being large enough, i.e. the flow resistance of the exhalation valves is not low enough to direct all the exhaled air to the outside. Therefore, the majority of the exhaled air first flows into the ventilation hose and is partly pushed back into the compressor housing of the CPAP device.

Due to the high humidity of the air exhaled by the patient and the lower temperature in the compressor housing compared to the temperature of the exhaled air, water condenses here. In connection with fine dust, a breeding ground for microorganisms forms especially in the cracks and pores of soundproofing foams. Germs can get to such breeding grounds from the environment and from the patient himself. From there, infections reach the next patient as well as the environment with the air, which is particularly problematic when the devices are used in different clinics. Regular disinfection of these devices is only possible with gases because the electronics built into the devices do not survive the temperatures required for disinfection. Due to the numerous poorly accessible cavities in the compressor device, a long penetration time of the gases and an equally long flushing time after the disinfection must be guaranteed.

Furthermore, lung regulators are known in the prior art which are used for diving. Such a regulator is described, for example, in Lueger, Lexikon der Technik, 1960, Stuttgart. This regulator has one Pressure reducer, which reduces the pressure of the oxygen cylinder to about 5 bar. A membrane is provided in the regulator, on one side of which the ambient pressure, ie the water pressure when diving, is present and on the other side of which the air to be inhaled is located. Inhaling the air creates a slight negative pressure that causes the membrane to bend. The bending of the membrane is transferred to a valve using a lever. The more the membrane bends, the further the valve is opened. This ensures that the diver is provided with oxygen under the surrounding water pressure. With this lung regulator, exhalation takes place via a separate chamber via a non-return valve, so that water does not enter the chamber.

It is the object of the invention to provide a breathing valve, a valve body and a method which improve the hygiene in CPAP devices.

This object is achieved by a breathing valve according to claim 1, a valve body according to claim 12 and a method according to claim 15.

Preferred embodiments are the subject of the dependent claims.

An advantage of the breathing valve according to the invention is that the patient is provided with better air quality since, in contrast to the prior art, he breathes in only a small part of the air that has just been exhaled. The amount of air that is breathed in again after exhaling is limited to the air in the respiratory mask, in the tube between the valve and the respiratory mask and in the back room. The invention can also be used in Bi-PAP or multilevel devices.

The advantage of the fact that a first overpressure at the inlet defines a second overpressure at the breathing opening also when exhaling is that the patient is not forced to exhale against an even higher overpressure. Another advantage of this embodiment is that when used together with a Bi-PAP device or a multilevel device, it applies the lower pressure to the patient during the breathing phase.

The advantage of this is that when inhaling air from the inlet to the breathing opening and when exhaling from the breathing opening to the outlet, but never - at least not in the Significant amount - air flowing from the inlet to the outlet is that a lower pump power of the turbine is sufficient. This enables the use of a smaller turbine, for which a less powerful power supply can be used. In this way, weight and cost savings can be realized. If a rotor or rotor of the same size is used in the turbine, its speed can be reduced, which leads to a reduction in the noise level generated by the turbine. This means that smaller silencers can be used and / or quieter CPAP devices can be developed. The reduced power requirement of the ventilator in connection with weight and possible volume reduction leads to an expansion of the mobility of the ventilator.

An advantage of a reduction in the clear cross section of a housing part of the breathing valve by means of webs 23 is that if the CPAP device fails, the valve body is moved into the antechamber in such a way that the valve body clamps due to the overpressure in the breathing opening that occurs during exhalation. Now the patient can inhale and expire through the outflow channel.

An advantage of dividing the valve housing into two parts and dividing the two stops for the valve body into one of the two parts is that the valve can be easily disassembled for cleaning purposes.

Finally, the exhalation valve according to the invention is small and light, so that it can be inserted between the ventilation mask and the ventilation hose without any problems.

A preferred embodiment of the invention is explained in more detail below with reference to the accompanying drawing.

1 shows a breathing valve according to the invention.

The valve according to the invention essentially consists of three parts: housing part 1, connecting piece 2 and valve body 3. The connecting piece 2 snaps into the housing part 1. Lugs 4 and groove 5 are provided for this purpose, the lugs engaging in groove 5. The flanks of the lugs and / or the groove are designed obliquely - that is, not perpendicular - to the longitudinal axis 6, so that the connecting piece 2 can be pulled out of the housing part 1 with moderate effort. In the preferred embodiment, the groove 5 forms an annular recess in the housing part 1, so that the socket 2 snaps into the housing so that it can rotate about the longitudinal axis 6. The valve body 3 preferably has a cylindrical outer shape and slides easily but radially almost without play in the housing part 1. The hose of the ventilator is pushed onto the standard cone 7 of the connector 2. The standard cone 8 of the housing part fits into the connection piece of a respiratory mask. The standard cones 7 and 8 have an outer diameter of approximately 18 mm.

During the inspiration phase, fresh air flows from the ventilator into the nozzle 2. In the inlet 21 and the anteroom 9, there is an overpressure in relation to the patient-side rear space 10 and the breathing opening 22. The valve body 3 is pressed in the direction of the rear space 10 into the position shown in FIG. 1. It opens the opening 12 from the antechamber 9 into the overflow channel 11. The fresh air flows through connection piece 2, anteroom 9, overflow channel 11, back space 10 and breathing opening 22 into the respiratory mask to the patient.

During the transition to the expiration phase, the pressure in the back room 10 increases, while it is kept constant in the anteroom 9 by pressure regulation of the CPAP device. The valve body 3 moves into the antechamber 9. When the antechamber-side edge 13 of the valve body reaches the antechamber-side edge 14 of the opening 12, the opening 12 is completely closed. Simultaneously or somewhat later, with further movement of the valve body 3 into the antechamber 9, the rear edge 15 of the valve body 3 begins to open the opening 16 to the outflow channel 17. The openings 12 and 16 are thus arranged and the length of the valve body is selected such that at most one of the openings 12 or 16 is open. The exhaled air now flows from the patient out of the breathing mask through the breathing opening 22, the back space 10, the opening 16 and the outflow channel 17 into the open. The movement of the valve body 3 into the antechamber 9 during the expiration only takes place until a pressure equilibrium between the rear chamber 10 and the anteroom 9 is reached. The opening 16 is therefore generally not completely opened, but only to the extent that the pressure set in the ventilator in the rear space 10 is maintained.

In order to avoid noise when the valve body 3 strikes the stops 19, the edges 15 and 13 of the valve body 3 and / or the stops 19 and 20 themselves can be made of a soft material or with a different such suspension are provided. The suspension can be implemented by inserting helical springs between the stops 20 or the rear edge 15 of the valve body 3 and / or the stops 19 and the front edge 13 of the valve body 3. The springs can also be dimensioned such that they hold the valve body in a preferred position, provided that there is no overpressure generated by the CPAP device at the inlet 21. In a preferred position, the valve body clears the second opening 16 so that the patient can breathe in or out through the outflow channel.

As mentioned above, the opening 16 is only opened by the valve body 3 to such an extent that when the patient exhales in the breathing opening 22 and back space 10, the pressure set on the CPAP is just reached. Thus, in normal operation, the opening 16, in cooperation with the overpressure generated by the CPAP device, represents a soft stop for the valve body 3. For this reason, the stops 19 are arranged in the preferred embodiment such that the valve body does not yet have these stops touches when its rear edge 15 just clears the opening 16 completely. Consequently, in this preferred embodiment, only the stops 20 and / or the rear edge 15 of the valve body 3 are made of a soft material.

As mentioned above, housing part 1, connecting piece 2 and valve body 3 are essentially rotationally symmetrical to the longitudinal axis 6. The overflow channel 11 preferably extends around one half of the outer surface of the housing part 1 in an approximately 180 ° sector. It therefore forms an approximately semi-cylindrical jacket. The overflow channel is 5 to 8 mm wide in the radial direction and the opening 12 in the axial direction in the preferred embodiment. Similarly, the opening 16, the outflow channel 17 and the outlet 18 extend around the other half of the outer surface of the housing part 1. The length of the opening 16 in the axial direction and the width of the outflow channel 17 in the radial direction is likewise 5 in the preferred embodiment up to 8 mm.

The outlet 18 of the outflow channel 17 is constructed in a particularly sound-reducing form, for example as a laminar nozzle. In order to keep noise generated by exhaled air at the outlet 18 as low as possible, the outlet 18 must have the largest possible area. Therefore, another is preferred Embodiment of the outflow channel 17 extends beyond the opening 12 in the axial direction towards the inlet 21, so that the outlet 18 can extend rotationally symmetrically at a 360 ° angle to the longitudinal axis 6 around the housing part 1. Where the overflow channel 11 allows, ie essentially from the antechamber-side edge 14 in the direction of the nozzle 2, the outflow channel widens from a 180 ° segment to a 360 ° segment.

In a further embodiment, wedges 23 are provided. The wedges 23 narrow the clear cross section of the housing part 1, so that the wedges ensure increased friction between the valve body 3 and the housing part 1. The edges of the wedges 23 facing the valve body 3 are arranged in such a way that the valve body 3 does not yet reach these edges when the rear-side edge 15 of the valve body 3 is just completely opening the opening 16. With this arrangement of the wedges, the valve body 3 does not touch the wedges as long as the CPAP device delivers an overpressure via the connector 2. However, if the CPAP device fails, so that no excess pressure inhibits the movement of the valve body in the direction of connection 2 when the patient exhales, the valve body is clamped by wedges 23, so that the patient via opening 16, outflow channel 17 and outlet 18 can both exhale and inhale.

The wedges 23 lead to a moderately increased friction between the valve body 3 and the housing part 1. However, the friction is so low that the valve body 3 can be blown out of the housing part 1 with the nozzle 2 removed or at least pressed out of the housing part 1 with a finger can. Accordingly, the valve body 3 can be reinserted into the housing part 1 with moderate effort, for example after it has been cleaned.

In a further preferred embodiment, the valve body 3 has elevations on its outer lateral surface. Only these elevations of the valve body 3 touch the inner wall of the housing part 1, so that the frictional force between the housing part 1 and the valve body 3 is reduced. An annular elevation near the rear-side edge 15 and a further annular elevation on the antechamber-side edge 13 of the valve body 3 are preferably provided. In order to effectively reduce the frictional force, the width of these ridges is less than the axial length of the openings 12 and 16 and is, for example, 1 mm. Thus, if the elevation is near the edge 13 on the antechamber just at the level of the opening 12, form a leakage air flow from the inlet 21 through the space between the outer surface of the valve body 3 and the inner surface of the housing part 1 to the opening 16. In this position, the increase is in the vicinity of the rear edge 15 of the valve body 3 between the stop 20 and the opening 16. This leakage flow is preferably largely prevented by a third annular increase around the outer surface of the valve body 3 approximately in the middle of the valve body. On the other hand, the leakage flow does not dramatically reduce the effect of the breathing valve since it only occurs for a short time during the movement of the valve body.

If the valve body has annular elevations on its lateral surface and these elevations are just at the level of the opening 12 or 16, the valve body 3 tends to tilt. This tendency to tilt can be reduced by providing webs 24 in the openings 12 and 16 for better guidance of the valve body. In another embodiment, 3 to 5 elevations are preferably provided on the lateral surface of the valve body 3, which extend away from the annular elevations on the edges 15 and 13 in the axial direction. The length of the latter increases in the axial direction is somewhat longer than the length of the corresponding openings 12 and 16 in the axial direction. The width of the latter elevations in the radial direction corresponds approximately to the width of the annular elevations and is significantly less than the length of the openings 12 and 16 in the axial direction, which is approximately 5 to 8 mm.

In another embodiment, the elevations can be provided inside the housing part 1 instead of on the valve body. Here, two elevations, which are rotationally symmetrical with respect to the longitudinal axis 6, are preferably provided between the openings 12 and 16, one close to the opening 12 and another close to the opening 16.

Due to the small pressure differences of less than 30 mbar, the clearance between the valve body 3 and the housing part 1 is accepted in order to achieve low friction between the valve body and the housing part. The resulting leaks can be tolerated since the flow in laminar flow between two walls is proportional to the square of the distance between the walls. In any case, the gap between housing part 1 and valve body 3 should be small. be compared to the radial width of the overflow channel 11, so that the leakage flow is small compared to the flow through the overflow channel.

LIST OF REFERENCE NUMBERS

1 housing part

2 sockets

3 valve bodies

5 4 noses

5 groove

6 longitudinal axis

7 standard cone

8 standard cone

10 9 anteroom

10 back room

11 overflow channel

12 first opening

13 edge on the vestibule side

15 14 edge of the opening on the vestibule side

15 rear edge

16 second opening

17 outflow channel

18 exit

20 19 stops

20 strokes

21 admission

22 breath opening

23 wedges

25 24 bridge

Claims

claims

1. Breathing valve for CPAP devices with

an inlet (21), an outlet (18) and a breathing opening (22),

characterized in that

a device (3, 11, 12, 16, 17, 18) is provided which prevents a substantial proportion of the exhaled air from being discharged via the inlet (21).

2. Breathing valve according to claim 1, characterized in that the device (3, 11, 12, 16, 17, 18) is designed such that during expiration the exhaled air is discharged essentially via the outlet (18).

3. Breathing valve according to one of the above claims, characterized in that the device (3, 11, 12, 16, 17, 18) is designed such that a first overpressure at the inlet (21) with respect to the ambient pressure is always a second overpressure between Breathing opening (22) and environment defines.

4. Breathing valve according to one of the above claims, characterized in that the device (3, 11, 12, 16, 17, 18) is designed such that either air to be inhaled from the inlet (21) to the breathing opening (22) or exhaled air from the breathing opening (22) flows to the outlet (18).

5. Breathing valve according to one of the above claims, characterized in that the device is formed by a movable valve body and a first opening (12) to an overflow channel (11), wherein the overflow channel (11) the inlet (21) with the Breathing opening (22) connects, wherein the valve body and the housing of the breathing valve are designed so that the valve body is moved so that it is the first by the excess pressure in the breathing opening (22) during expiration relative to the pressure at the inlet (21) Closes opening (12) and is moved by the negative pressure created during inspiration so that it releases the first opening (12).

6. Breathing valve according to one of claims 1 to 4, characterized in that the device is formed by a movable valve body and a second opening (16) to an outlet (18), the valve body and the housing of the breathing valve being designed such that the valve body is moved by the overpressure which arises from the expiration in the breathing opening (22) relative to the inlet (21) in such a way that it opens up the second opening (16) and vice versa the valve body is moved by the one in the breathing opening during inspiration

(22) resulting negative pressure is moved so that it closes the second opening (16).

7. Atemventjl according to one of claims 5 or 6, characterized in that the valve housing from a first housing part (1) and a second

Part (2) consists, both parts being separable, each part providing a stop (20, 19) for the movement of the valve body (3) and the valve body being able to be removed from the valve housing when the two parts are separated.

8. Breathing valve according to claim 6 and 7, characterized in that the stops (19), which restrict the movement of the valve body during expiration, are arranged so that the valve body does not touch the stops (19) when a first overpressure in the inlet the ambient pressure prevails and the stops (20), which restrict the movement of the valve body during inspiration, are made of a soft material.

9. Breathing valve according to claim 7, characterized in that in the vicinity of the stops (19) which restrict the movement of the valve body during expiration, the inner cross section of the valve housing (1, 2), for example by wedges

(23) is narrowed in order to generate significant friction between the valve body (3) and valve housing (1, 2).

10. Breathing valve according to claim 5, characterized in that the housing (1, 2) of the breathing valve and the valve body (3) are essentially rotationally symmetrical, the overflow channel (11) with the first opening (12) rotationally symmetrical in a 130 ° to 230 ° large sector is formed and a

5 second opening (16), which can also be closed by the valve body, is arranged rotationally symmetrically in the remaining 230 ° to 130 ° sector.

11. Breathing valve according to claims 6, 8, 9 or 10, characterized in that an outflow channel (17) with the second opening (16) is connected to the

10 its outlet (18) forms a laminar nozzle.

12. Valve body for use in a breathing valve according to one of the above claims.

15 13. Valve body according to claim 12, characterized in that the valve body is rotationally symmetrical with an essentially cylindrical outer surface.

14. Valve body according to claim 12 or 13, characterized in that the 20 valve body has on its outer circumferential surface in the direction of movement front and rear circumferential ridges.

15. Procedure for performing CPAP therapy with the steps:

25 inspiring fresh air that has not yet been inhaled by the patient from a ventilation tube, and

Expire the used air into the surroundings by the patient.

16. The method according to claim 15, characterized in that the expiration takes place against a therapy pressure relative to the ambient pressure.