DEVICE AND SYSTEM FOR RESPIRATORY SUPPORT

Abstract

The present invention relates to a device (100) and a system for positive pressure ventilation (PPV) and continuous positive airway pressure (CPAP) treatment comprising a fresh gas flow inlet (2), arranged to receive a fresh gas flow from a fresh gas flow tube (22) connectable thereto; a patient interface end (3), arranged to be connected with a patient interface; an outlet (4) having an open end (5); a variable flow CPAP generator (6) comprising first, second and third connection portions (10, 11, 12), wherein the first connection portion is connected with the fresh gas flow inlet, the second connection portion is connected with the patient interface end, and the third connection portion is connected with the outlet, wherein the generated CPAP level is adjusted by varying the fresh gas flow to the variable flow CPAP generator. The device further comprises an internal leakage channel (9) arranged to extend between the fresh gas flow inlet and at least one of the patient interface end and the outlet, such to create an internal fresh gas leakage flow there between, bypassing the first connection portion of the variable flow CPAP generator, which is added to the fresh gas flow provided by the variable flow CPAP generator in the PPV mode. A simplified device and system is provided, respectively, which is easy to use and allows for a rapid switch between PPV and CPAP treatment without change of equipment.

Claims

1. A device for positive pressure ventilation (PPV) and continuous positive airway pressure (CPAP) treatment comprising: a fresh gas flow inlet, arranged to receive a fresh gas flow from a fresh gas flow tube connectable thereto; a patient interface end, arranged to be connected with a patient interface; an outlet having an open end; a variable flow CPAP generator comprising first, second and third connection portions, wherein the first connection portion is connected with the fresh gas flow inlet, the second connection portion is connected with the patient interface end, and the third connection portion is connected with the outlet, wherein the generated CPAP level is adjusted by varying the fresh gas flow to the variable flow CPAP generator; and an internal leakage channel arranged to extend between the fresh gas flow inlet and at least one of the patient interface end and the outlet, such to create an internal fresh gas leakage flow there between, bypassing the first connection portion of the variable flow CPAP generator, which internal fresh gas leakage flow is added to the fresh gas flow provided by the variable flow CPAP generator in the PPV mode.

2. The device according to claim 1, wherein the internal leakage channel comprises a hole through an internal wall portion of the device.

3. The device according to claim 1, wherein the internal leakage channel partially extends through the second connection portion of the variable flow CPAP generator to the patient interface end of the device.

4. The device according to claim 3, wherein a hole is provided through an internal wall portion which extends between the fresh gas flow inlet and the second connection portion of the variable flow CPAP generator.

5. The device according to claim 1, wherein the internal leakage channel partially extends through the third connection portion of the variable flow CPAP generator to the outlet of the device.

6. The device according to claim 5, wherein a hole is provided through an internal wall portion which extends between the fresh gas flow inlet and the third connection portion of the variable flow CPAP generator.

7. The device according to claim 1, further comprising a pressure release connection portion, arranged partially in parallel with the second connection portion of the variable flow CPAP generator, and having a first end connected with the patient interface end of the device and a second end connectable with a pressure release tube, wherein the internal leakage channel partially extends through the pressure release connection portion to the patient interface end of the device.

8. The device according to claim 7, wherein a hole is provided through an internal wall portion which extends between the fresh gas flow inlet and the pressure release connection portion.

9. The device according to claim 1 where the fresh gas flow provided to the variable flow CPAP generator is 5-15 liters per minute.

10. A system for PPV and CPAP treatment comprising a device according to claim 1, a fresh gas flow tube, a fresh gas source connected with the fresh gas flow inlet by means of the fresh gas flow tube, and a pressure release valve arranged to prevent an excessive positive pressure in a PPV mode.

11. The system according to claim 10, arranged such that when the open end of the outlet of the device is occluded, the pressure will increase from the variable flow CPAP generator until an opening pressure of the pressure release valve is reached, which increase in pressure results in an inspiratory flow, whereby the pressure in the system will remain at the set PPV pressure until the occlusion is removed from the outlet, and when the occluded outlet is opened, the pressure will return to the set CPAP level, whereby the reduction in pressure leads to an expiratory flow.

12. The system according to claim 10, arranged such that during spontaneous breathing, the infant flow and the fresh gas flow leaves the system through the variable flow CPAP generator keeping the positive pressure within the airway stable, by varying the flow that generates the CPAP, whereby the CPAP in the airway can be adjusted as needed.

13. The system according to claim 10, wherein the pressure release valve is connected with one of the patient interface end and the outlet of the device.

14. The system according to claim 10, further comprising a pressure measuring device.

15. Use of a device according to claim 1 in PPV and CPAP treatment for neonatal resuscitation.

16. Use of a system according to claim 10 for PPV and CPAP treatment for neonatal resuscitation.

17. The device according to claim 2, wherein the internal leakage channel partially extends through the second connection portion of the variable flow CPAP generator to the patient interface end of the device.

18. The device according to claim 17, wherein a hole is provided through an internal wall portion which extends between the fresh gas flow inlet and the second connection portion of the variable flow CPAP generator.

19. The device according to claim 2, wherein the internal leakage channel partially extends through the third connection portion of the variable flow CPAP generator to the outlet of the device.

20. The device according to claim 2, further comprising a pressure release connection portion, arranged partially in parallel with the second connection portion of the variable flow CPAP generator, and having a first end connected with the patient interface end of the device and a second end connectable with a pressure release tube, wherein the internal leakage channel partially extends through the pressure release connection portion to the patient interface end of the device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The invention will now be described in more detail and with reference to the appended drawings. The drawings are included to provide a further understanding of the present invention and are incorporated in and are a part of this specification. Other embodiments of the present invention, and many of the intended advantages of the present invention, will be readily appreciated as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale relative to each other. The same reference numerals designate corresponding similar parts.

[0040] FIG. 1a is a schematic cross-sectional illustration of an embodiment of the device according to the present invention;

[0041] FIG. 1b is a schematic cross-sectional illustration of another embodiment of the device according to the present invention;

[0042] FIG. 1c is a schematic cross-sectional illustration of yet another embodiment of the device according to the present invention;

[0043] FIGS. 2a-c schematically illustrate embodiments of the system according to the present invention;

[0044] FIGS. 3a-b schematically illustrate flows of the system shown in FIG. 2a during positive pressure ventilation; and

[0045] FIG. 4 schematically illustrates flows in the system shown in FIG. 2a during spontaneous ventilation.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0046] Examples of different embodiments of the present invention are provided. Common for the embodiments of the device for PPV and CPAP treatment described herein is that they comprise a fresh gas flow inlet 2, a patient interface end 3, an outlet 4 having an open end 5, a variable CPAP generator 6, and an internal leakage channel 9. Furthermore, the variable flow CPAP generator 6 comprises a first connection portion 10, a second connection portion 11, and a third connection portion 12. In all embodiments, the fresh gas flow inlet 2 is connected with the first connection portion 10 of the variable flow CPAP generator 6; the patient interface end 3 is connected with the second connection portion 11; and the third connection portion 12 is connected with the outlet 4 of the device. The outlet 4 is typically tubular and arranged as a protruding tube ending having a free open end 5. The patient interface end 3 of the device is connectable with any patient interface, such as for example a face mask, nasal prongs, or an endotracheal tube.

[0047] The first, second and third connection portions 10, 11, 12 of the variable flow CPAP generator 6 are generally tubular. In the embodiments shown herein, the second and third connection portions 11, 12 of the variable flow CPAP generator 6 are arranged at an angle to each other. Further, the first connection portion 10 is connected with the third connection portion 12 at an angle, and is arranged substantially coaxially with the second connection portion 11. Such a geometry of the variable flow CPAP generator 6 is advantageous as it provides a stable CPAP generated by the variable flow CPAP generator 6, and a low imposed work of breathing for the patient when in use. However, providing first, second and third connection portions 10, 11, 12 of the variable flow CPAP generator 6 having a different geometry is also conceivable within the concept of the present invention.

[0048] The internal leakage channel 9 may also be called internal bypass flow channel, since in the embodiments and operation modes the internal fresh gas leakage flow will bypass the first connection portion 10 of the variable CPAP generator 6 and will thereby not flow there through. The internal leakage channel 9 can be arranged in several different positions, see FIGS. 1a-c.

[0049] With reference to FIG. 1a, according to a first embodiment of the device 100, the internal leakage channel 9 extends between the fresh gas flow inlet 2 and the patient interface end 3 through an internal wall portion 13 which extends between the fresh gas flow inlet 2 and a pressure release connection portion 14 of the device 100. The pressure release connection portion 14 is generally tubular forms a passage through a portion of the device 100. More particularly, the pressure release connection portion 14 extends partially in parallel with the second connection portion 11 of the variable flow CPAP generator 6 and comprises a first end 16 and a second end 17. The first end 16 is connected with the patient interface end 3 of the device 100 and the second end 17 is connectable to a pressure release tube 15, see FIG. 2a. Thus, the internal leakage channel 9 extends through the internal wall portion 13, which is present between the fresh gas flow inlet 2 and the pressure release connection portion 14, and further through the pressure release connection portion 14 to the patient interface end 3 of the device 100.

[0050] As disclosed in FIG. 1b, according to a second embodiment of the device 200, the internal leakage channel 9 extends between the fresh gas flow inlet 2 and the outlet 4 of the device 200. In this exemplifying embodiment, the internal leakage channel 9 extends through the internal wall portion 18 which is present between fresh gas flow inlet 2 and the third connection portion 12 of the variable flow CPAP generator 6, and further through the third connection portion 12 to the outlet 4 of the device 200. Thus, the internal leakage channel 9 partially extends through the third connection portion 12 of the variable flow CPAP generator while bypassing the first connection portion 10. This provides a compact device 200.

[0051] According to yet another embodiment of the device 250, shown in FIG. 1c, the internal leakage channel 9 extends between the fresh gas flow inlet 2 and the patient interface end 3 of the device 250, partially through the second connection portion 11 of the variable flow CPAP generator 6. For this, a portion of the internal leakage channel 9 is provided as a hole through an internal wall portion 24 of the device 250 which extends between the fresh gas flow inlet 2 and the second connection portion 11 of the variable flow CPAP generator 6. Another portion of the internal leakage channel 9 thus extends through the second connection portion 11 to the patient interface end 3.

[0052] In the shown embodiments, the hole is substantially straight, and may be e.g. a bore. This allows adapting previous devices used for CPAP and PPV treatment, as that mentioned in the background of the invention, by providing a bore between a fresh gas flow inlet 2 and one of the patient interface end 3 and the outlet 4, bypassing the first connection portion 10 of the variable flow CPAP generator 6 and removing any second fresh gas flow tube. However, the skilled person will understand from the teaching of the present disclosure that providing an internal leakage channel 9 of any other shape or extension than those described herein with reference to the exemplifying embodiments is also possible within the concept of the present invention, provided that it extends between the fresh gas flow inlet 2 and one of the patient interface end 3 and the outlet 4, and bypasses the first connection portion 10 of the variable flow CPAP generator 6.

[0053] A first embodiment of the system 300, as disclosed in FIGS. 2a, 3a-b and 4, comprises the embodiment of the device 100 described with reference to FIG. 1a. The system 300 further comprises a fresh gas source 20, which provides a fresh gas flow to the fresh gas flow inlet 2 through a fresh gas flow tube 22 of the system 300. The level of CPAP is adjusted at the fresh gas source 20. The system further comprises a pressure release valve 7 and a pressure measuring device 8. The pressure release valve 7 and the pressure measuring device 8 can be arranged in several different positions, see FIGS. 2 a-c. The pressure measuring device 8 can be omitted in any embodiment, however, if there is no interest in measuring the pressure. In the exemplifying embodiments shown in FIGS. 2a and 2b, the system further comprises a pressure release tube 15 connected to the pressure release connection portion 14. The pressure release valve 7 and the pressure measuring device 8 are here connected to the pressure release connection portion 14 through the pressure release tube 15.

[0054] A second embodiment of the system 400, as disclosed in FIG. 2b, comprises an embodiment of the device comprising a pressure release connection portion 14, and in which the internal leakage channel 9 extends between the fresh gas flow inlet 2 and the outlet 4 of the device. The system 400 comprises a pressure release tube 15 connected to the pressure release connection portion 14. The pressure release valve 7 is arranged at an end of the pressure release tube 15 which is distal to the pressure release connection portion 14. The pressure measuring device 8 is arranged at the pressure release tube 15 between the pressure release valve 7 and the pressure release connection portion 14.

[0055] A third embodiment of the system 500, as disclosed in FIG. 2c, comprises the embodiment of the device 200 described with reference to FIG. 1b. In this exemplifying embodiment, the pressure release valve 7 is arranged in connection with the outlet 4 of the device 200. More particularly, the system 500 comprises an outlet tube 19 connected to the outlet 4 of the device 200 through its open end 5. The pressure release valve 7 is arranged along the outlet tube 19. The outlet tube 19 comprises an open end 23. Further, in this exemplifying embodiment, the pressure measuring device 8 is arranged close to the patient interface end 3 of the device 200.

[0056] The system is operated as follows. Reference will be made to the first embodiment of the system 300, but the second embodiment and third embodiments have a corresponding operation. Oxygen concentration and fresh gas flow are adjusted by a standard blender and a flow meter. The fresh gas flow can be varied and is typically set to between 5 and 15 litres per minute. More preferably, the fresh gas flow is set to between 10 and 12 litres per minute. A fresh gas flow in this range should prevent rebreathing, provide flow to achieve an adequate inspiration flow, volume and time, and provide some allowance for leakage in the patient interface, in addition to the internal leakage provided by the internal leakage channel 9.

[0057] The fresh gas flow is used to drive the variable flow CPAP generator 6. However, inside the device, a part of the fresh gas flows through the internal leakage channel 9 bypassing at least the first connection portion 10 of the variable flow CPAP generator 6. The internal bypass flow, i.e. the internal fresh gas leakage flow, is used to supply adequate flow for positive pressure ventilation by bypassing the variable flow CPAP generator 6. The internal bypass flow is connected in such a way that it adds to inspiratory patient flow when the device 1 is occluded during positive pressure ventilation. The fresh gas flow to the variable flow CPAP generator 6 is adjustable. A typical value of the fresh gas flow provided to the fresh gas flow inlet 2 is 5-15 liters per minute. To provide higher levels of CPAP, the flow driving the variable flow CPAP generator 6 can be increased further. For a same size of the internal leakage channel 9, i.e. for a same device 100, 200, a further increased driving flow generates a CPAP level that is higher than normally used. However, a device can be provided with an internal leakage channel 9 generating a greater leakage, e.g. by providing an increased diameter of the internal leakage channel 9, for which an increased drive flow is required to provide a certain level of CPAP. In the PPV mode, when occluding the open end 5 of the device 100, 200, the greater leakage and higher drive flow results in an increased flow added to the fresh gas flow generated by the variable flow CPAP generator 6, and thus to a faster increase in pressure.

[0058] The outlet 4 of the variable flow CPAP generator 6 has an open end 5. If the open end 5 is occluded, see FIGS. 2a and 3a, the pressure delivered to the infant will increase from the pressure set by the variable CPAP generator 6 until the opening pressure of the pressure release valve 7 is reached. A typical value for the pressure release valve 7 to open is around 20-30 cm H.sub.2O. The increase in pressure results in an inspiratory flow. The pressure in the system 300 will remain at the set positive pressure ventilation pressure until the outlet occlusion is removed. When the occluded open end 5 is opened, see FIG. 3b, the pressure delivered to the patient will return to the set CPAP level and this reduction in pressure will lead to an expiratory flow.

[0059] During spontaneous breathing the infant flow and the fresh gas flow leaves the system 300 through the variable flow CPAP generator 6, see FIG. 4. This keeps the positive pressure within the airway stable. By varying the flow, i.e. the fresh gas flow, that generates the CPAP pressure, the CPAP pressure in the airway can be adjusted as needed.

[0060] The patient interface end 3 can be designed in any suitable form such to be suitable for connection with a patient interface. Further, the patient interface can assume a variety of designs suitable for establishing a connection to the patient nasal airways, not shown. Thus, the patient interface can include an opposing pair of nasal prongs, a mask, an endotracheal tube or any other suitable devices.

[0061] The system 300, 400, 500 could have a backup system for malfunctioning of the pressure release valve 7. This could either be an alarm, a second release valve or a system that cuts the fresh gas flow.

[0062] The pressure measuring device 8 should be positioned as close to the patient as possible to provide accurate recording of the pressure of the gas delivered to the patient. The accuracy will depend on the flow resistance of the patient interface and, for an infant, a low resistance interface should be used if possible. The embodiment of the device described with reference to FIG. 1b could be regarded as beneficial since there will be less tubes needed in the system 500.

[0063] Notably, the device, in accordance with principles of the present invention is useful with a wide variety of patient interface configurations that may or may not incorporate some or all of the features described above with respect to the patient interface. Thus, the patient interface is in no way limiting.

[0064] Notably, the device, in accordance with principles of the present invention is useful with a wide variety of variable flow CPAP generators that may or may not incorporate some or all of the features described above with respect to the variable flow CPAP generator 6. Thus, the model of the variable flow CPAP generator 6 is in no way limiting.

[0065] Notably, the device, in accordance with principles of the present invention is useful with a wide variety of pressure release valves 7 or similar devices that achieve the purpose of releasing air depending on the pressure in the system. Thus, the model or type of pressure release valve is in no way limiting.

[0066] Notably, the device, in accordance with principles of the present invention is useful with a wide variety of pressure measuring devices 8 or similar devices that achieves the purpose of measuring the pressure in the system. Thus, the model or type pressure measuring devices is in no way limiting.

[0067] A typical CPAP level for resuscitating or stabilising an infant is in the range of 3-10 cm H.sub.2O. A typical peak pressure for PPV is 20-30 cm H.sub.2O. It is obtained by occluding the systems and having a correctly adjusted pressure release valve.

[0068] Above embodiments of the device and system according to the present invention as defined in the appended claims have been described. These should only be seen as merely non-limiting examples. As understood by the person skilled in the art, many modifications and alternative embodiments are possible within the scope of the invention as defined by the appended claims. For example, according to an embodiment, the device comprises several variable flow CPAP generators, each being connected to the fresh gas flow inlet, the patient interface end and the outlet of the device. Together with the internal leakage channel, extending between the fresh flow gas inlet and at least one of the patient interface end and the outlet of the device, this allows operating the device at a high fresh gas flow while maintaining a stable level of CPAP in the CPAP mode. Further, in the PPV mode, the rise time, i.e. the time necessary for reaching a predetermined airway pressure of a patient when the open end of the outlet is occluded, is reduced.

[0069] According to another embodiment, the device comprises several internal leakage channels, each extending between the fresh gas flow inlet and one of the patient interface end and the outlet of the device. For example, a device may comprise first and second internal leakage channels wherein the first internal leakage channel extends between the fresh gas flow inlet and the patient interface end, and the second internal leakage channel extends between the fresh gas flow inlet and the outlet of the device. Providing several internal leakage channels also allows providing a higher fresh gas flow to the device while maintaining a stable CPAP level in the CPAP mode and decreasing the rise time in the PPV mode.

[0070] It is to be noted that for the purposes of his application, and in particular with regard to the appended claims, the word “comprising” does not exclude other elements or steps, and the word “a” or “an” does not exclude a plurality, which per se will be evident to a person skilled in the art.