NON-INVASIVE VENTILATION SYSTEM FOR THE PRE-HOSPITAL MANAGEMENT OF ACUTE RESPIRATORY FAILURE

Abstract

A stand-alone continuous positive airways pressure, CPAP, apparatus having a face-mask and a connected electro-mechanical device to supply air to the face-mask is disclosed. The electro-mechanical device includes a pneumatic channel for flowing air to be delivered to the face mask and a control unit for managing the air pressure of the air inside the pneumatic channel. The CPAP apparatus includes a turbine fan, located in the electro-mechanical device housing, connected to the control unit for pressurizing atmospheric air. The pneumatic channel includes an inlet portion located upstream of the turbine fan to receive atmospheric air, and an outlet portion located downstream of the turbine fan to deliver the pressurized air to the face-mask through an outlet opening. The pneumatic channel also longitudinally extends from the inlet portion to the outlet portion.

Claims

1. A stand-alone continuous positive airways pressure, CPAP, apparatus comprising: a face-mask to deliver continuous pressured air to a patient's airways, and an electro-mechanical device having a housing directly and rigidly connectable to the face-mask to supply air to said face-mask at a controlled pressure value, the electro-mechanical device comprising a pneumatic channel for flowing air to be delivered to the face-mask and a control unit for automatically managing the value of the pressure of the air inside the pneumatic channel, wherein the apparatus comprises a turbine fan connected to the control unit and located in the housing of the electro-mechanical device for pressurizing atmospheric air to a determined pressure level value, and wherein the pneumatic channel includes an inlet portion located upstream of the turbine fan to receive atmospheric air and an outlet portion located downstream of the turbine fan to deliver the pressurized air to the face-mask through an outlet opening, the pneumatic channel extending longitudinally in the housing from said inlet portion to said outlet portion.

2. The apparatus of claim 1, further comprising connection means located between the face-mask and the housing of the electro-mechanical device for allowing the face-mask to be detachable from said housing, wherein the connection means optionally comprise a snap-fit fastening mechanism or a screwing mechanism.

3. The apparatus according to claim 1, wherein the turbine fan is located outside the pneumatic channel that delivers pressurized air to the face-mask and then to the patient.

4. The apparatus according to claim 1, wherein the pneumatic channel has a central longitudinal axis (CA) passing through the outlet opening and the turbine fan is located at a predetermined distance from said central longitudinal axis (CA).

5. The apparatus according to claim 4, wherein the turbine fan has a rotational axis (RA) parallel to the central longitudinal axis (CA) of the pneumatic channel and wherein said rotational axis (RA) is shifted from said central longitudinal axis (CA).

6. The apparatus according to claim 4, wherein the housing at the outlet portion has an end region having a tapered shape.

7. The apparatus according to claim 1, wherein the face-mask comprises a mechanical exhaust valve for automatically opening an air connection to the atmosphere in case the pressure level value in the pneumatic channel exceeds a preset threshold pressure value.

8. The apparatus of claim 1, wherein the electro-mechanical device comprises a first filter located upstream of the turbine fan to protect the turbine fan from external contaminants.

9. The apparatus of claim 1, wherein the electro-mechanical device comprises a second filter located downstream of the turbine fan to purify the pressured air to be delivered the face-mask wherein the second filter optionally is a high efficiency particulate air, HEPA, filter.

10. The apparatus of claim 1, wherein the electro-mechanical device comprises a controlled exhaust valve for opening an air connection to the atmosphere, the controlled exhaust valve being located at the outlet portion of the pneumatic channel and being connected to the control unit.

11. The apparatus of claim 1, wherein the electro-mechanical device comprises a first pressure sensor and a second pressure sensor, independent from the first pressure sensor, both pressure sensors being located at the outlet portion of the pneumatic channel and being connected to the control unit to measure the pressure value in the pneumatic channel.

12. The apparatus of claim 11, wherein the control unit comprises a fan speed control unit to adjust the pressure value inside the pneumatic channel by modifying the speed of the turbine fan based on the pressure value measured by the first pressure sensor.

13. The apparatus of claim 10, wherein the control unit comprises an overpressure detector to activate the controlled exhaust valve and to stop the action of the turbine fan based on the pressure value measured by the second pressure sensor.

14. The apparatus of claim 1, wherein the electro-mechanical device further comprises a rechargeable battery pack to supply at least the control unit and the turbine fan.

15. A non-invasive ventilation system comprising an apparatus of claim 1 and a diagnostic and power supply unit connected to the apparatus for supplying current to a battery unit of the apparatus and for displaying information on the actual status of the apparatus components.

Description

[0032] Preferred embodiments of a stand-alone CPAP apparatus and the non-invasive ventilation system in accordance with the invention will be explained herein below in greater detail with reference to the accompanying drawings, in which:

[0033] FIGS. 1a, 1b and 1c show a perspective view of the stand-alone CPAP apparatus according to the present invention in an assembled configuration with a face-mask (a), in a disassembled configuration (b), and in a section configuration without the face-mask (c);

[0034] FIG. 2 shows a block diagram of the apparatus;

[0035] FIGS. 3a and 3b show a schematic representation of the position of the turbine fan with respect to the pneumatic channel in the housing of the apparatus; and

[0036] FIG. 4 shows a non-invasive ventilation system according to the present invention.

[0037] FIG. 1a describes a schematic representation of a stand-alone CPAP apparatus 1 according to the present application. The apparatus 1 comprises a face-mask 10 and an electro-mechanical device 20 connected to the face-mask 10. It is noted that the electro-mechanical device 20 is directly connected to the face-mask 10 in a rigid fashion. In other words, between the mask 10 and the electro-mechanical device 20 are not interposed any kind of flexible elements, such as electrical cable, or flexible tubes or ducts. In this way, the apparatus 1 is a stand-alone apparatus that can easily be handle also with a single hand. FIG. 1a also illustrates the presence of a mechanical exhaust valve 12 located on a side of the face-mask 10 acting as a safety means in case of overpressure.

[0038] The face-mask 10 can easily be detached by the electro-mechanical device 20, or rather by the housing 22 of said device 20, as illustrated in FIG. 1b. For this purpose, connection means 14 are located between the face-mask 10 and the device 20. The face-mask 10 can be detached and reattached to the housing 22 of the electro-mechanical device 20 thanks to, for example, a snap-fit fastening mechanism. Sealing elements are provided at the connection means for avoiding air escape from this conjunction region.

[0039] FIG. 1c describes the longitudinal section of the electro-mechanical device 20 of FIGS. 1a and 1b. The electro-mechanical device 20 includes a housing 22 that is directly connected to the face-mask 10. In particular, the electro-mechanical device 20 comprises a pneumatic channel 24 configured to allow the flowing of the air from the external environment to the face-mask 10, the pneumatic channel 24 having an inlet portion 241 for receiving atmospheric air from outside (two dark arrows on the bottom in FIG. 1c) and an outlet portion 242 for delivering pressurized air to the face-mask 10 through the outlet opening 21 (single white arrow on the top in FIG. 1c). It is noted that the housing 22 has the shape of a bottle, wherein at the outlet portion 242 the housing 20 has an end region 23 having a tapered shape. In the housing 22 is located a turbine fan 28 for pressurizing the atmospheric air received from outside at a predetermined pressure value. Upstream of the turbine fan 28 is located a coarse filter 243 to avoid the damage of the fan 28 caused by macroscopic contaminants. Downstream of the turbine fan 28 is on the other hand located a HEPA filter 244 to purify the pressurized air to be delivered to the face-mask 10.

[0040] The electro-mechanical device 20 further comprises a first pressure sensor 246 and a second pressure sensor 247. Both sensors are used to measure the pressure value inside the pneumatic channel 24 and are located downstream of the turbine fan 28 at the outlet portion 242 of the pneumatic channel. In addition, the electro-mechanical device 20 comprises a controlled exhaust valve 245 for opening an air connection to the atmosphere (with side arrow in FIG. 1c). The controlled exhaust valve 245 is located at the outlet portion 242 of the pneumatic channel 24.

[0041] At a side of the pneumatic channel 24, the electro-mechanical device 20 further comprises a control unit 26. The control unit 26 automatically manages the normal and abnormal pneumatic conditions of the apparatus. For this reason, the two pressure sensors 246, 247, the controlled exhaust valve 245, as well as the turbine fan 28 are connected to the control unit 26.

[0042] As shown in FIG. 1c, the control unit 26 is supplied by a low-voltage supply line 29, backed-up by a battery pack 27 for short-time stand-alone needs.

[0043] FIG. 2 illustrates a functional schematic representation of the electro-mechanical device 20 connected to the face-mask 10. Atmospheric air (horizontal arrow on the left side of FIG. 2) is introduced into the apparatus 1 and is filtered by the coarse filter 243. After passing through the turbine fan 28, the pressurized air is additionally filtered by the HEPA filter 244.

[0044] In normal operating mode, the control unit 26 is configured to adjust the pressure value inside the pneumatic channel 24 by modifying the speed of the turbine fan 28 based on the pressure value measured by the first pressure sensor 246. For this purpose, the control unit 26 comprises a fan speed control unit 261 connected to the turbine fan 28 and the first pressure sensor 246. Based on the information (i.e. the measured pressure value) received by the first pressure sensor 246, the fan speed control unit 261 acts on the speed of the turbine fan 28, for example by decelerating its functioning until reaching a controlled pressure value inside the pneumatic channel 24. At this point, the pressured air is first delivered to the face-mask 10 and then to the patient P.

[0045] In abnormal overpressure operating mode, the control unit 26 is configured to activate the controlled exhaust valve 245 and to stop the action of the turbine valve 28 based on the pressure value measured by the second pressure sensor 247. For this purpose, the control unit 26 comprises an overpressure detector 262 connected to the turbine fan 28, the controlled exhaust valve 245 and the second pressure sensor 247. Based on the information (i.e. the measured pressure value) received by the second pressure sensor 247, the overpressure detector 262 activates the controlled exhaust valve 245 and acts on the speed of the turbine fan 28, for example stopping its functioning. In this case, the over-pressurized air is expelled by the controlled exhaust valve 245 (vertical arrow at the controlled exhaust valve 245).

[0046] As an additional safety control element, before the pressurized air is delivered to the patient P, the face-mask 10 is provided with a mechanical exhaust valve 12. In case the pressure value of the air inside the mask is above a pre-set threshold value, the over-pressurized air is expelled by the mechanical exhaust valve 12 (vertical arrow at the controlled exhaust valve 12).

[0047] FIGS. 3a and 3b show a schematic representation of the housing 22 of the electro-mechanical device 20 and in particular the relative position of the turbine fan 28 with respect to the pneumatic channel 24. From the figures it is clear that the pneumatic channel 24 can be represented by a duct connecting the inlet portion to the outlet portion of the housing 22. In this particular case, the channel 24 is a longitudinal channel extending basically in the central internal part of the housing 22. According to the two configurations illustrated in the figures, the turbine fan 28, schematically depicted as a circle, is located outside the pneumatic channel 24. FIGS. 3a and 3b shows two possibilities, wherein the turbine fan 28 is located on the left side or the right side of the pneumatic channel 24. However, it is clear that the turbine fan 28 can be positioned in any region inside the housing 22 that is outside the channel 24. In particular, the pneumatic channel 24 has a central longitudinal axis CA that passes through the outlet opening 21 of the housing 22. Accordingly, the turbine fan 28 is located at a predetermined distance d from the central longitudinal axis CA. The value of the distance is determined to avoid a direct conduction of toxic fumes or heated air from the turbine fan 28 to the outlet opening 21.

[0048] It is noted that the rotational axis RA of the turbine fan 28 is parallel to the central longitudinal axis CA of the pneumatic channel 24 and the rotational axis RA is shifted from the central longitudinal axis CA. In particular, the distance d between the two parallel axes is determined to avoid a direct conduction of toxic fumes or heated air from the turbine fan 28 to the outlet opening 21. Although not shown in the figure, the rotational axis RA of the turbine fan 28 can be oriented in a different direction compared to the central axis CA of the pneumatic channel 24. This configuration can avoid the direct conduction of toxic fumes or heated air from the turbine fan 28 to the outlet opening 21 as well.

[0049] FIG. 4 illustrates a schematic representation of a non-invasive ventilation system 100 for the pre-hospital management of acute respiratory failure. This system can be located in a public place outside an hospital structure, such as a subways, a school, university, etc. The system 100 comprises the apparatus 1 as described in FIGS. 1a, 1b and 1c and a diagnostic and power supply unit 2 that is connected to the apparatus through connection means 3, for example electrical cables. The diagnostic and power supply unit 2 is configured to supply current to a battery unit of the apparatus 1. Also, this unit 2 is configured for displaying information on the actual status of the apparatus components. To this purpose, the diagnostic and power supply unit 2 comprises a display 4 and control lights 5 for informing the user on the charge status of the battery 27 inside the apparatus 1 or on possible malfunctioning of some components of the apparatus 1, such as the control unit 26, the turbine fan 28, the battery 27, the sensors 246, 247, the valve 245, etc.

[0050] Whilst features have been presented in combination of the above description, this is intended solely as an advantageous combination. The above description is not intended to show required combinations of features, rather it represents each of the aspects of the disclosure. Accordingly, it is not intended that any described specific combination of features is necessary for the functioning of the stand-alone CPAP apparatus or the non-invasive ventilation system.