WO2009103111A1

WO2009103111A1 - Patient's breathing detection and monitoring

Info

Publication number: WO2009103111A1
Application number: PCT/AU2009/000182
Authority: WO
Inventors: Charles Rupert Russell-Smith
Original assignee: Charles Rupert Russell-Smith
Priority date: 2008-02-19
Filing date: 2009-02-19
Publication date: 2009-08-27

Abstract

An apparatus for detecting sound in gas flow in a respiratory line, the apparatus comprising a body (10) having a first opening (16) and a second opening (17) between which gas can flow through the body (10), the body (10) comprising sound detection means (23) for detecting sound in the gas flow. A method for detecting and/or monitoring sound in a respiratory line comprising exposing a sound detection means to the gas flow and measuring output of sound detection means to provide an indication of the sounds of gas flow within the respiratory line.

Description

Patient's breathing Detection and Monitoring

Field of the Invention

The present invention relates to apparatus and methods for detecting and/or monitoring a patient's breathing, and more particularly sound generated by or as a consequence of the breathing process. The sound detected may, of course, comprise various sounds produced during the breathing process.

Background Art

The following discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application.

In one method of general anaesthesia, a patient is connected to anaesthetic circuit tubes via an endotracheal tube or laryngeal mask. A housing having a filter is connected between the anaesthetic circuit tubes and the mask to prevent bacteria and/or viruses passing from the patient into the anaesthetic circuit. This may also be configured to humidify the gases delivered to the patient.

Patients under general aesthetic are usually connected to a number of tubes, monitoring devices, intravenous feeds and/or medication feeds. This makes it difficult for medical staff to physically access the patient's chest to monitor their breathing and as such, it is possible that the patient's breathing is not checked until there is a noticeable problem. Patients under general aesthetic can become wheezy or have fluid in their lungs and these conditions should be detected as early as possible.

It is the object of the present invention to substantially overcome the above disadvantages. Disclosure of the Invention

According to a first aspect of the invention there is provided an apparatus for detecting sound in a gas flow in a respiratory line, the apparatus comprising a body having a first opening and a second opening between which gas can flow through the body, the body comprising sound detection means for detecting sound in the gas flow.

The sound detected is sound generated by gas flow (typically air) within the respiratory system of a patient; specifically, air flow within the patient's airways and lungs. The sound generated can provide an indication of the breathing function of the patient; that is, whether the patient is breathing normally or abnormally. The sound generated may, for example, provide an indication as to whether the patient is wheezing or has an breathing state associated with a disease involving the respiratory system such as asthma.

The sound detected typically comprises various sounds produced during the breathing process

Preferably, the sound detection means comprises a transducer.

Preferably, the body further comprises a gas outlet adapted to deliver gas to a gas monitoring unit.

Preferably, the body further comprises a gas outlet for taking samples of the gas.

Preferably, the respiratory line is adapted to receive gas from a gas source.

Preferably, the gas source is within an anaesthetic circuit

Preferably, the sound detection means comprises a microphone. Preferably, the apparatus further comprises means for detecting output of the sound detection means and to produce signals indicative of the sound in the gas flow.

Preferably, the body further comprises a housing defining an internal space, the housing having the first opening in connection to a patient's air intake device and the second opening in connection to the gas source, the housing having an opening closed by the sound detection means and a cover extending over the sound detection means forming a listening space between the sound detection means and the cover, wherein a listening port adapted to detect output of the sound detection means is in communication with the listening space.

Preferably, the apparatus further comprises the patient's air intake device may be selected from the group consisting of an oxygen mask, an endotracheal tube and a laryngeal mask.

Preferably, the cover is slideably attached to the housing.

Preferably, the sound detection means comprise at least one diaphragm for producing acoustic waves in response to the sounds in the gas flow.

Preferably, the listening port is adapted to receive a tube of a stethoscope for listening of the acoustic waves produced by the diaphragm.

Preferably, the listening port is adapted to receive a microphone for listening of the acoustic waves produced by the diaphragm.

Preferably, the housing comprises the outlet for taking samples of the gas.

Preferably, the housing comprises the outlet adapted to deliver gas to a gas monitoring unit. - A -

Preferably, the second opening is connected to a filter assembly prior to connection to the gas source.

Preferably, the body further comprises means for conditioning the gas.

Preferably, the means for conditioning comprises filter means and/or humidification means for conditioning the gas.

Preferably, the sound detected comprises sounds generated during exhalation in the respiratory process.

According to a second aspect of the invention there is provided a method for detecting and/or monitoring the breathing of a patient, the method comprising use of the apparatus previously described.

According to a third aspect of the invention there is provided a method for detecting and/or monitoring sound in a respiratory line comprising exposing a sound detection means to the gas flow and measuring output of the sound detection means to provide an indication of the sounds of the gas flow within the respiratory line.

Preferably, the step of exposing sound detection means to the gas flow comprises inserting the sound detection means into the respiratory line.

According to a third aspect of the invention there is provided a gas conditioning assembly for conditioning gas to be delivered to a patient comprising a housing defining an internal space adapted to condition the gas, the housing being adapted to receive sound detection means for detecting sounds from the gas flow within the housing. Preferably, the internal space comprises filter means and/or humidification means for conditioning the gas.

Brief Description of the Drawings

Preferred forms of the present invention will now be described by way of examples only with reference to the accompanying drawings wherein:

Figure 1 is a perspective view of an assembly according to a first arrangement of the second embodiment of the present invention;

Figure 2 is a front view of the assembly of Figure 1 ;

Figure 3 is a side cross-section view of the assembly of Figure 1 ;

Figure 4 is a side view of an assembly according to a second arrangement of the second embodiment of the present invention;

Figure 5 is a bottom view of the assembly of Figure 4 being partially open to show the filter element;

Figure 6 is an exploded perspective view of the assembly of Figure 4;

Figure 7 is a perspective view of the top plate of the assembly of Figure 4; and

Figure 8 is a perspective view of the cover plate of the assembly of Figure 4.

Best Mode(s) for Carrying Out the Invention

Throughout the specification and claims, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. A first embodiment of the invention comprises detecting and/or monitoring sounds in the gas flow in a respiratory line attached to a patient via a sound detection means, such as a microphone. The output of the microphone may be transformed into signals (for example, audible signals) or displayed via electronic means on displays and/or transformed with help of appropriate software. The detecting and/or monitoring of the gas flow sounds provides an indication of the breathing conditions of the patient.

The sounds within the respiratory line may be detected by exposing to the gas flow the transducing face of the microphone (the side of the microphone comprising the transducer). The gas flow activates the transducer generating an output such as an electric current. Exposing of the transducing face of the microphone may be accomplished by making an incision in the tube (the respiratory line) adjacent the patient's air intake device. The incision is such that a tight fit for the microphone is provided. Alternatively, the transducing face of the microphone may be inserted into the housing that filters the gas provided to the patient.

The sounds in the respiratory line will activate the transducer. The output of the transducer can be then converted to any type of signals, such as, for example audible signals or images displayed on screens for detection and/or monitoring of the gas flow. The output of the transducer and/or the signals may be analysed by computers programs such as AUDACITY™ software. The obtained graphic display can be shown on the anaesthetic monitor screen.

Figures 1 to 3 show an assembly 10 according to a second embodiment of the present invention. The assembly 10 includes a housing 11 which is substantially shaped as a rectangular prism. The housing includes a first face 12, a second face 13, and side faces 14 extending therebetween to form an internal space 15 within the housing 11. The first face 12 includes a first tubular formation 16 which is in communication with the internal space 15. The second face 13 includes a second tubular formation 17 which is also in communication with the internal space 15. The first tubular formation 16 is adapted for attachment to a tube connected to the patient's air intake device while the second tubular formation 17 is adapted for attachment to a tube connected to the anaesthetic circuit. The first and second tubular formations 16 and 17 are located adjacent the lower end of the first and second faces 12 and 13 and are substantially aligned with each other to form a gas flow path 18 which passes through the internal space 15.

Means for conditioning the gas may be placed in the internal space. For example, a filter element 19 is placed within the internal space 15 which extends between the internal surfaces of the side walls 14. Thus, gas travelling along the flow path 18 between the first and second tubular formations 16 and 17 will pass through the filter element 18. Gas humidification means among others may also be included in the internal space.

The first face 12 of the housing 11 further includes a diaphragm opening 20 which is formed adjacent its upper end. A cover 21 is attached to the first face 12 which extends over the diaphragm opening 20. The cover 21 includes a seat 22 for holding a diaphragm 23 therein. When the cover 21 is attached to the first face 12, the diaphragm 23 is located to extend across and cover the diaphragm opening 20. One side of the diaphragm 23 is thus exposed to the internal space 15 and the other side of the diaphragm 23 is exposed to a second space 24 between the diaphragm 23 and the cover 21. The cover 21 includes a listening port 25 which is in communication with the second space 24. The listening port 25 is dimensioned for attachment to a tube of a stethoscope. The second face 13 of the housing includes a carbon dioxide (CO₂) sampling port 26 which is in communication with the internal space 15.

In use, the first tubular formation 16 is attached to the tube connected to the patient's air intake device. The second tubular formation 17 is attached to a tube connected to the anaesthetic circuit. The CO₂ sampling port 26 is attached to a tube connected to a CO₂ monitor. When the patient inhales, gas travels in the flow path direction 18a from the anaesthetic circuit through the filter element 19 and out through the first tubular formation 16 into the patient's air intake device. The patient's air intake device may be an oxygen mask, an endotrachael tube or a laryngeal mask, among others. When the patient exhales, exhaled gas travels in the reverse flow path direction 18b from the first tubular formation 16, through the filter element 19 and out through the second tubular formation 17. The sounds in the gas flow - typically during exhalation- will make the diaphragm 23 vibrate creating acoustic pressure waves in the second space 24. The patient's breathing can then be monitored by, for example, attaching a stethoscope tube to the listening port 25. A typical stethoscope tube can be attached to the listening port 25 by removing the chestpiece assembly from the stethoscope tube.

The present invention thus provides an assembly which allows medical staff to monitor a patient's breathing substantially without having to physically lean over the patient and over other medical equipment. If a stethoscope is attached to the listening port 25, medical staff can quickly monitor and assess the patient's breathing for any distinct changes or other signs.

Figures 5 to 8 show a second arrangement of the first embodiment of the invention. This arrangement 30 is similar to the arrangement 10 and similar parts will be referred to with similar reference numerals.

The assembly 30 includes a housing 11 having a first face 12, a second face 13, and side faces 14 extending therebetween to form an internal space 15 within the housing 11. The first face 12 in this arrangement is a portion of a top plate 32 which is slidably attachable to the side walls 14 of the housing 11 to form the internal space 15. As shown in Figures 6 and 7, the top plate 32 includes internally extending ridges 33 spaced from the first face 12 for engaging outwardly extending flanges 34 of the side walls 14. The first face 12 includes a first tubular formation 16 which is in communication with the internal space 15. The second face 13 includes a second tubular formation 17 which is also in communication with the internal space 15. The first tubular formation 16 is adapted for attachment to a tube connected to the patient's air intake while the second tubular formation 17 is adapted for attachment to a tube connected to the anaesthetic circuit. A filter element 19 is placed within the internal space 15 which extends between the internal surfaces of the side walls 14.

The first face 12 of the housing 11 includes a diaphragm opening 20. In this arrangement, a diaphragm 23 is attached to the first face 12 to cover the diaphragm opening 20. A cover plate 21 is then attached to the first face 12 which extends over the diaphragm 23. One side of the diaphragm 23 is thus exposed to the internal space 15. The cover plate 21 includes a recess 35 therein to provide a second space 24 between the diaphragm 23 and the cover 21. The cover 21 includes a listening port 25 which is in communication with the second space 24. The second face 13 of the housing includes a carbon dioxide (CO₂) sampling port 26 which is in communication with the internal space 15.

Alternatively to the above, the cover 21 can include a seat for holding the diaphragm 23 wherein when the cover 21 is attached to the first face 12, the diaphragm 23 is located to extend across and cover the diaphragm opening 20. Use of the device 30 is similar to that of the device 10 above.

The present invention thus provides an assembly which allows medical staff to monitor a patient's breathing substantially without having to physically lean over the patient and over other medical equipment, either by listening to the sounds emanating from the patient circuit or by viewing a display on a monitor screen. Medical staff can quickly monitor and assess the patient's breathing for any distinct changes or other signs. Although embodiments of the present invention have been described, it will be apparent to skilled persons that modifications can be made to the embodiments described. For example, the diaphragm assembly can be a separate assembly to the filter housing. In this embodiment, the assembly will essentially be similar to the above embodiments but without the filter element 19. Such a separate assembly can then be connected in series connection with the filter housing. Essentially, such an assembly will expose one side of the diaphragm to the gas flow from the patient which creates acoustic waves at the other side of the diaphragm which can then be monitored. Alternatively, the filter housing may be adapted to receive transducer means for detecting flow of the gas within the filter housing.

In a further arrangement, the listening port 25 can be connected to electronic monitoring equipment capable of detecting the diaphragm vibration. Then, the electronic equipment may display or output monitored results as desired, such as a patient's breathing pattern or raising an alarm if gas flow stops or any abnormality in the gas flow occurs. Examples of other means capable of detecting the diaphragm vibration are, for example, laser base systems which measure light intensity reflecting from the vibrating diaphragm.

As a further modification, a microphone can be connected to the listening port 25 and further alternatively, the diaphragm 23 can be removed and a microphone can be connected to the listening port 25. Any type of microphone may be used. Examples of microphones are dynamic microphones, piezoelectric microphones, fiber optical microphones, among others.

Moreover, the diaphragm may be replaced with any type of transducer for detecting and monitoring sounds in the gas flow. Any type of transducer that converts the gas flow movement to a measurable signal may be used. The transducer may be any selected from piezo-electric, magnetic, among others. In other arrangements the assembly 10 (30) may be adapted to receive electronic monitoring equipment capable of detecting the transducer means output and emit signals and/or display images associated with the gas flow within the assembly 10 (30) and thus with the patient's breathing.

Claims

The Claim Defining the Invention is as Follows:

1. An apparatus for detecting sound in gas flow in a respiratory line, the apparatus comprising a body having a first opening and a second opening between which gas can flow through the body, the body comprising sound detection means for detecting sound in the gas flow.

2. An apparatus according to claim 1 wherein the sound detection means comprises a transducer.

3. An apparatus according to claims 1 or 2 wherein the body further comprises a gas outlet adapted to deliver gas to a gas monitoring unit.

4. An apparatus according to claim 1 wherein the body further comprises a gas outlet for taking samples of the gas.

5. An apparatus according to any one of claims 1 to 4 wherein the respiratory line is adapted to receive gas from a gas source.

6. An apparatus according to claim 5 wherein the gas source is within an anaesthetic circuit

7. An apparatus according to any one of claims 1 to 6 wherein the sound detection means comprises a microphone.

8. An apparatus according to any one of claims 1 to 7 further comprising means for detecting output of the sound detection means and to produce signals indicative of the sound in the gas flow.

9. An apparatus according to any one of the previous claims wherein the body further comprises a housing defining an internal space, the housing having the first opening in connection to a patient's air intake device and the second opening in connection to the gas source, the housing having an opening closed by the sound detection means and a cover extending over the sound detection means forming a listening space between the sound detection means and the cover, wherein a listening port adapted to detect output of the sound detection means is in communication with the listening space.

10.An apparatus according to claim 9 wherein the patient's air intake device may be selected from the group consisting of an oxygen mask, an endotracheal tube and a laryngeal mask.

11.An apparatus according to any one of claims 9 and 10 wherein the cover is slideably attached to the housing.

12.An apparatus according to any one of claims 9 to 11 wherein the sound detection means comprise at least one diaphragm for producing acoustic waves in response to the sounds in the gas flow.

13.An apparatus according to claim 12 wherein the listening port is adapted to receive a tube of a stethoscope for listening of the acoustic waves produced by the diaphragm.

14.An apparatus according to claim 12 wherein the listening port is adapted to receive a microphone for listening of the acoustic waves produced by the diaphragm.

15.An apparatus according to any one of claims 9 to 14 wherein the housing comprises the outlet for taking samples of the gas.

16.An apparatus according to any one of claims 9 to 14 wherein the housing comprises the outlet adapted to deliver gas to a gas monitoring unit.

17. An apparatus according to any one of claims 1 to 16 wherein the second opening is connected to a filter assembly prior to connection to the gas source.

18. An apparatus according to any one of claims 1 to 16 wherein the body further comprises means for conditioning the gas.

19. An apparatus according to claim 18 wherein the means for conditioning comprises filter means and/or humidification means for conditioning the gas.

20.An apparatus according to any one of the preceeding claims wherein the sound detected comprises sounds generated during exhalation in the respiratory process.

21. A method of detecting and/or monitoring the breathing of a patient, the method comprising use of apparatus according to any one of claims 1 to 20.

22.A method for detecting and/or monitoring sound in a respiratory line comprising exposing a sound detection means to a gas flow in the respiratory line and measuring output of the sound detection means to provide an indication of the sounds in the gas flow.

23.A method according to claim 22 wherein the step of exposing sound detection means to the gas flow comprises inserting the sound detection means into the respiratory line.

24.A method according to claim 22 or 23 wherein the sound detected comprises sounds generated during exhalation in the respiratory process.

25.A gas conditioning assembly for conditioning gas to be delivered to a patient comprising a housing defining an internal space adapted to condition the gas, the housing being adapted to receive sound detection means for detecting sounds from the gas within the housing.

26.A conditioning assembly according to claim 25 wherein the internal space comprises filter means and/or humidification means for conditioning the gas.

27.An apparatus for detecting gas flow in a respiratory line delivered by a gas source, the apparatus as herein described with reference to the accompanying drawings.

28.A method for detecting and/or monitoring sounds with in a respiratory line of a patient, the method as herein described with reference to the accompanying drawings.

29. A gas conditioning assembly for conditioning gas to be delivered to a patient, the gas conditioning assembly as herein described with reference to the accompanying drawings.