GB2512047A

GB2512047A - Positive Expiratory Pressure Device With Electronic Monitoring

Info

Publication number: GB2512047A
Application number: GB1304742.8A
Authority: GB
Inventors: Benjamin Wolf Heller; Martin James Wildman
Original assignee: Sheffield Hallam University
Current assignee: Sheffield Hallam University
Priority date: 2013-03-15
Filing date: 2013-03-15
Publication date: 2014-09-24
Anticipated expiration: 2033-03-15
Also published as: GB2512047B; GB201304742D0; WO2014140532A1

Abstract

An electronic device for monitoring the passage of air through a positive expiratory pressure (PEP) device 100 comprises a sensor, such as a pressure transducer (206, figure 2), positioned within a housing 109 and configured to identify a change in pressure corresponding to the start or end of a breath exhaled into the device. A data recorder automatically logs pressure and time and may increase the sampling rate when a breath is detected. The duration of each breath is measured and recorded. The monitoring device may be incorporated into a detachable mouthpiece 101. The mouthpiece (figure 2) is divided into a first airway portion (201) and a second measurement portion (211) by a wall. An opening in the wall is sealed by a flexible diaphragm (204) and covered by a cap to form a chamber (203). A conduit (208) connects the chamber to the pressure transducer (206) which is mounted on a microcontroller (207) itself mounted on a PCB (212).

Description

Positive Expiratory Pressure Device With Electronic Monitoring

Field of invention

The present invention relates to an electronic monitoring device suitable for use with a positive expiratory pressure (PEP) device and in particular, although not exclusively to a device having a sensor configured to detect a change in pressure within the device and a time recorder to record a time period associated with the start and end of a flow of air through the device corresponding to a patient exhaling into the device.

Background art

Bronchial drainage chest physiotherapy (CR1') is a typical clinical treatment for the mobilisation and removal of airway secretions in a variety of different respiratory conditions including in particular cystic fibrosis, brochiectasis, bronchitis, bronchial asthma, primary ciliary dyskinesia syndrome. This type of therapy has proven to be effective to maintain pulmonary function and inhibit respiratory complications in patients with chronic conditions. However, standard CPT is very intensive with regard to labour and time for both hospitalised and non-hospitalised patients.

More recently, a number respiratory therapeutic devices have emerged as alternatives to standard CPT that are less time consuming to use and offer greater independence for a patient with chronic lung disease. Whilst such devices may not be as effective as CPT, they offer alternative therapy methods for improving mobilisation of mucus from the airways and in turn improving pulmonary fIrnction. Such devises are particularly usefhl where a patient is struggling to adhere to a conventional CPT programme.

An example positive expiratory pressure (PEP) device (commonly referred to as an airways clearance adjunct) is disclosed in EP 1103287 and comprises a housing having an internal airflow passageway extending between an inlet and an outlet. An oscillator is provided in communication with the passageway and is configured for obstructing and opening the airflow path so that a patient exhaling into the device via the inlet can experience an alternating resistance to flow through.

EP 1464357 also discloses a PEP device intended for multiple use and designed specifically to be easily assembled and disassembled for cleaning. The device is ifirther adapted such that its operation is positionally independent to facilitate manipulation and use during PEP therapy.

Cunently, the only mechanism for monitoring use of a conventional adjunct device involves a patient either making mental or written notes of their adherence to a particular therapeutic programme. For certain respiratory dysfunctions such as cystic fibrosis, adherence to a programme is essential for treatment effectiveness and this requires a patient be well ordered and maintain the prescribed routine. Insufficient or inappropriate treatment may be prescribed where a user has unintentionally or otherwise provided inaccurate details of their adjunct use which is a particular problem with younger users.

Accordingly, what is required is a PEP device and/or a complementary additional device that is configured for recording use by a patient as part of a prescribed clinical therapeutic programme.

Summary of the Invention

It is an objective of the present invention to provide an electronic monitoring device suitable for use with a positive expiratory pressure (PEP) device configured to monitor use of the device automatically thereby avoiding a patient having to record their own usage via an independent recording scheme.

The objectives are achieved by providing an electronic monitoring device having a sensor and a time recorder that may form a component part of a PEP device or may be a component attachable to such a device and being sensitive to airflow passage through the device (corresponding to a patient exhaling). In particular, the present device comprises a sensor, preferably in the form of a pressure transducer or switch together with a time recordal component such that the start and end of a single patient expiration through the device is identifiable. Preferably, the device comprises a processor in the form of a microcontroller together with a non-volatile memory suitable to record expiration patterns through the device as a patient repeatedly exhales into it during single and multiple prescribed therapeutic sessions. Accordingly, the present device is configured to calculate breath duration, flow rate, flow volume and breath velocity for example. In specific implementations where the device comprises a pressure transducer i.e. a continuous sampling configuration, the frequency and amplitude of wave form oscillations may be monitored which in turn can be used to confirm i) the device is working properly and ii) the vibration speed and frequency which, are helpful to a clinician in assessing and prescribing the clinical programme. The device may also comprise additional components such as wired and wireless conmiunication ports and data storage facilities to allow a patient to build and transfer respiratory performance data for their own use and that of the responsible clinician to both monitor therapy adherence and performance.

According to a first aspect of the present invention there is provided an electronic monitoring device suitable for monitoring the passage of air through a positive expiratory pressure (PEP) device, the monitoring device comprising: a housing having an internal chamber with an airflow inlet and an airflow outlet to allow a flow of air through the internal chamber; a sensor positioned within the housing and configured to detect a change in pressure within the chamber including the start of a flow of air through the chamber and a tennination of a flow of air through the chamber; and a time recorder to measure a time period between a detected change in pressure within the chamber corresponding to a start and a termination of a flow of air through the chamber.

Preferably, the device comprises a partition extending in a direction between the inlet and the outlet to separate the internal chamber into a passageway for the flow of air between the inlet and the outlet and a compartment to accommodate the sensor and timer recorder such that the sensor and the time recorder are separated from the flow of air through the passageway by the partition. More preferably, the device further comprises a diaphragm extending between a region of the passageway and the compartment and capable of deforming in response to a pressure change in the passageway. Preferably, the sensor is coupled to the diaphragm so as to be responsive to a pressure change in the compartment created by displacement of the diaphragm.

Preferably, the device further comprises a processor coupled electronically to the sensor arid the time recorder. More preferably, the processor is a microcontroller configured to control the sensor according to at least two modes of operation including a sleep mode having a first sample rate and a breath mode having a second sample rate, wherein the second sample rate is greater than the first sample rate.

Optionally, the device thrther comprises any one or a combination of the following set of: a battery; a non-volatile memory; a sounder; an optical output device. Preferably, the time recorder is an electronic real time clock.

Optionally, the device fhrther comprises any one or a combination of the following set of: a wireless communication component; a wired communication component; a data storage component; an optical display.

Preferably, the sensor comprises a pressure transducer. Alternatively, the sensor may comprise a pressure switch.

According to a second aspect of the present invention there is provided an oscillatory positive expiratory pressure (PEP) therapy device comprising an electronic monitoring device as claimed herein.

According to a third aspect of the present invention there is provided a positive expiratory peak flow meter comprising an electronic monitoring device as claimed herein.

According to a fourth aspect of the present invention there is provided an oscillatory positive expiratory pressure (PEP) therapy device comprising: a housing having an internal chamber and an airflow inlet and an airflow outlet to allow a flow of air through the internal chamber; an oscillator accommodated within the housing in communication with the airflow path between the inlet and the outlet, the oscillator configured for obstructing and opening the airflow path so that a patient exhaling into the device via the inlet can experience an alternating resistance to flow through the device; a sensor positioned within the housing and configured to detect a change in pressure within the internal chamber including the start of a flow of air through the internal chamber and a termination of a flow of air through the internal chamber; a time recorder to record a time period between a detected change in pressure within the internal chamber corresponding to the start and termination of the flow of air through the internal chamber.

Preferably, the device further comprises a mouthpiece releasably connectable to the inlet of the PEP therapy device, the mouthpiece comprising a housing having an internal chamber and an inlet and an outlet to allow a flow of air through the internal chamber; wherein the sensor and the time recorder are accommodated within the mouthpiece housing.

Preferably, the device is a hand-held airways adjunct. Optionally, the device may be a hand-held peak flow meter.

In one aspect of the present invention the sensor for identifying a pressure change in the internal passageway of the device is a flow rate sensor or a temperature sensor. Other electronic components may also be employed for this purpose and are suitable if they can identify a change in the environmental state within the passageway indicative of a breath through the device being resultant from a user breathing into it.

Brief description of drawings

A specific implementation of the present invention will now be described, by way of example only, and with reference to the accompanying drawings in which: Figure 1 is an external perspective view of an oscillatory positive expiratory pressure (PEP) therapy device connectable with an electronic monitoring device, in the form of a mouthpiece attachable to the PEP device according to a specific implementation of the present invention; Figure 2 is a cross sectional side elevation view of the mouthpiece component of figure 1; Figure 3 is a cross sectional side elevation view of the PEP therapy device of figure 1; Figure 4 is a schematic illustration of various components of the electronic monitoring device of figure 1; Figure 5 is schematic flow diagram of the control of the pressure transducer by a microcontroller according to three different pressure sampling modes according to a specific implementation of the present invention; Figure 6 illustrates an expiratory wave form of a patient that has exhaled through a PEP device comprising electronic pressure monitoring according to one aspect of the present invention.

Detailed description of preferred embodiment of the invention Referring to figure 1, an airways adjunct device 100 comprises a main housing 102 having a generally hollow cylindrical configuration. A short tube section 108 extends axially from a first end 110 of housing 102. Tube 108 comprises an open outermost first end that forms an inlet 103 for the adjunct 100. An opposed second end ill of housing 102 also comprises a short tube 112 having an open outermost end that forms an air intake 115. As illustrated, tube 108, housing 102 and tube 112 are aligned concentrically about central longitudinal axis 113. The device 100 further comprises a plurality of airflow outlets 104 formed at regions of housing 102.

Adjunct 100 is connectable to a mouthpiece 101 attached to the inlet tube 108.

Mouthpiece 101 comprises a housing 109 defining an internal chamber having an inlet opening 106 and an outlet opening 105 positioned at opposite ends. A flange 107 extends around outlet 105 and is configured to mate around an outward facing surface of tube 108 so the tube 108 may be inserted within a region 114 about mouthpiece housing 109 to releasably secured mouthpiece 101 to adjunct 100.

Referring to figures 2 and 3 adjunct 100 comprises an internal chamber 311 defined by housing 102. A region of chamber 311 is partitioned by an internal wall 300 extending between inlet 103 and intake 115. Wall 301 defines an internal passageway 312 between inlet 103 and intake 115. An aperture or opening 301 is formed within a region of wall 300 towards intake end 115. Additionally, a one way flap valve 302 extends immediately in board of intake 115 and prevents air flowing out of device 100 at this region.

An oscillatory mechanism is mounted within chamber 311 externally of passageway 312 so as to extend over aperture 301. The mechanism comprises an elongate beam 304 mounted upon a pivot mounting 303 substantially at a mid-point along its length via a pivot pin 305. A weight 309 is provided at a first end 314 of beam 304 and a magnetically susceptible tab 307 is attached to a second end 308 of beam 304. A magnet arrangement 306 is mounted at an external region of passageway wall 300 so as to be positioned opposed to tab 307 in close contact. A conical plug 310 extends downwardly from an underside surface of beam 30410 project towards aperture 301 and is dimensioned with a diameter corresponding to a diameter of aperture 301. That is, beam 304 is configured to pivot laterally about pin 305 such that plug 310 is effected to completely close and open aperture 301. In use, air is introduced into passageway 312 as a user exhales into device 100 via inlet 103. The airflow path to outlet 104 is blocked by flap 302 such that air is prevented from flowing through opening 301. However, aperture 301 is closed by plug 310 until pressure at its underside increases sufficiently to overcome the attractive force of magnet 306 on tab 307. Once this occurs, beam 304 pivots via a sudden motion such that air escapes from housing 102 via outlet gills 313. As the pressure within passageway 312 drops, due to the flow of air through gills 313, beam 304 is pivoted in the opposite direction as magnet 306 draws tab 307 downwardly to close aperture 301 via plug 310. As a user continues to exhale, the pressure build-up through passageway 312 then acts to displace plug 310 in the same manner as described and the cycle is continued. The effect of the repeated and very rapid opening and closing of aperture 301 by plug 310 provides a vibratory resistance experience to the exhaled airflow of user which helps to dislodge mucus in their respiratory system and passageways.

Figure 2 illustrates the internal components of the mouthpiece part 101 of figure 1 comprising selected electronic components to provide an attachable electronic monitoring device for use with airways adjunct 100. Housing 109 defines an internal chamber 202.

Chamber 202 is divided about axis 113 by a partition wall 200 extending in a direction between inlet 106 and outlet 105 to define an airflow passageway 201. An opening aperture 210 is formed within partition 200. A flexible diaphragm 204 extends across and seals opening 210 to prevent the flow of air from passageway 201 beyond wall 200. A cap extends to cover diaphragm 204 and projects from the perimeter of opening 210 to define a pocket region 203 into which diaphragm 204 is capable of being displaced by a positive pressure within passageway 201. The use of a diaphragm 204 and the partitioning of the electronic components 206, 207 from the exhaled air within passageway 201 prevents both damage to the electronic components and provides a device 101 that may be easily cleaned to prevent and remove bacterial build up within housing chamber 202.

A compartment region 211 is created between housing 109 and the opposite side of partition wall 200 relative to passageway 201. Compartment 211 accommodates a plurality of electronic components including in particular a microcontroller 207 and a pressure transducer 206 coupled electronically to the microcontroller 207 which in turn is mounted upon a suitable PCB 212. A conduit 208 provides a link between sensor 206 and the diaphragm pocket 203 such that a change in pressure within the region of pocket 203 is detectable by sensor 206 as diaphragm 204 is displaced radially outward from passageway 201 and into pocket 203.

Mouthpiece 101 is attached to adjunct 100 as tube 108 is partially accommodated within region 114 of mouthpiece cavity 202. The device is then ready for use according to the therapeutic programme prescribed and to dislodge mucus within the passageways of the patient via the oscillatory motion of the beam 304.

Referring to figure 4, the electronic monitoring device 101 comprises a variety of different electronic components including in particular: a microcontroller 207 (such as a PlC 16LF series); a pressure transducer (such as a Honeywell TruStability1M sensor); a battery 400 (such as a CR2032); a non-volatile memory 402 (such as flash SDRAM); an optical display LED 403; an audio sounder 404; a real time clock 401 (such as a 32kHz watch crystal); a USB port 406 to interface with a PC and a wireless conmunication port/device 405 for wireless transfer of data from device 101 to a PC. As will be appreciated, the electronic components of figure 4 are mountable upon common PCB 212.

Microcontroller 207 is configured specifically to maximise the lifetime of battery 400.

This is achieved via software implementation and the control of the pressure transducer 206 according to a plurality of operative states. In particular, pressure transducer 206 is operated according to a first low' speed sample rate that may be approximately 1 sample per second; a second medium' speed sample state being approximately 10 to 20 cycles per second and; a high' sample speed rate being approximately 100 samples per second. The present device, via a microcontroller 207, is configured automatically to switch between the different transducer states in response to pressure changes within passageway 201.

In particular and referring to figure 5, transducer 206 is first operative in the low sample speed 500. At stage 501, if the pressure within passageway 201 (being monitored via transducer 206) exceeds a threshold value transducer 206 is adjusted to start high speed sampling 502 corresponding to user exhaling into device 101 via inlet 106. A breath start * time is recorded via clock 401. High speed sampling continues 503 until the pressure within passageway 201 drop below a predetermined value 504 to result in a recordal of an end of breath 506. Alternatively, the sample is recorded at 505 if the pressure is above the predetermined level. The breath characteristics are saved 507 via memory 402.

Transducer 406 downgrades to the medium sample state 508 and is then in a state waiting for a further breath. If a breath is detected via an increased pressure 509 the high speed sampling ioop is re-entered at 502. Transducer 206 may be configured to time-out' after for example one minute to revert to the low speed sampling rate 511 to restart the cycle 500. Alternatively transducer 206 reengages the medium sample rate 508 for possible high speed sampling and a new set of breath characteristic recordings.

Figure 6 illustrates a typical breath wave form resultant from a user exhaling into mouthpiece 101. The breath start is indicated by the initial peak 601. The pressure curve then decreases gradually until the end of breath peak 602. The intermediate oscillations 603 correspond to the oscillations of beam 304 and the resistance to the airflow through opening 301 via the oscillatory mechanism within the adjunct 100. As will be appreciated, via the pressure transducer 206 and recordal component 401, it is possible to generate the wave form profile 600 of figure 6 to enable the calculation of additional breath characteristics including for example: airflow speed, volume, vibration frequency and amplitude. This information is then useful both to a user of the device and a clinician in assessing and prescribing revised clinical procedures to optimise successful treatment.

Additionally memory storage may be provided to allow large data volume to be obtained and stored at device 101 for subsequent download to a PC via wired 406 or wireless 405 communication.

According to the specific implementation, monitoring device 101 is removably attachable to the PEP device 100. However, according to further specific implementations, device 101 may be formed integrally with PEP device 100 which, alternatively, may be a peak flow meter.

Claims

Claims 1. An electronic monitoring device suitable for monitoring the passage of air through a positive expiratory pressure (PEP) device, the monitoring device comprising: a housing having an internal chamber with an airflow inlet and an airflow outlet to allow a flow of air through the internal chamber; a sensor positioned within the housing and configured to detect a change in pressure within the chamber including the start of a flow of air through the chamber and a termination of a flow of air through the chamber; and a time recorder to measure a time period between a detected change in pressure within the chamber corresponding to a start and a termination of a flow of air through the chamber.
2. The device as claimed in claim 1 further comprising a partition extending in a direction between the inlet and the outlet to separate the internal chamber into a passageway for the flow of air between the inlet and the outlet and a compartment to accommodate the sensor and timer recorder such that the sensor and the time recorder are separated from the flow of air through the passageway by the partition.
3. The device as claimed in claim 2 comprising a diaphragm extending between a region of the passageway and the compartment and capable of deforming in response to a pressure change in the passageway.
4. The device as claimed in claim 3 wherein the sensor is coupled to the diaphragm so as to be responsive to a pressure change in the compartment created by displacement of the diaphragm.
5. The device as claimed in any preceding claim further comprising a processor coupled electronically to the sensor and the time recorder.
6. The device as claimed in claim 5 wherein the processor is a microcontroller configured to control the sensor according to at least two modes of operation including a sleep mode having a first sample rate and a breath mode having a second sample rate, wherein the second sample rate is greater than the first sample rate.
7. The device as claimed in any preceding claim further comprising any one or a combination of the following set of: * a battery * a non-volatile memory * a sounder * an optical output device.
8. The device as claimed in any preceding claim wherein the time recorder is an electronic real time clock.
9. The device as claimed in any preceding claim flirther comprising any one or a combination of the following set of: * a wireless communication component * a wired communication component * a data storage component * an optical display.
10. The device as claimed in any preceding claim wherein the sensor comprises a pressure transducer.
II. The device as claimed in any one of claims 1 to 9 wherein the sensor comprises a pressure switch.
12. An oscillatory positive expiratory pressure (PEP) therapy device comprising an electronic monitoring device as claimed in any one of the preceding claims.
13. A positive expiratoly peak flow meter comprising an electronic monitoring device as claimed in any one of the preceding claims.
14. An oscillatory positive expiratory pressure (PEP) therapy device comprising: a housing having an internal chamber and an airflow inlet and an airflow outlet to allow a flow of air through the internal chamber; an oscillator accommodated within the housing in communication with the airflow path between the inlet and the outlet, the oscillator configured for obstructing and opening the airflow path so that a patient exhaling into the device via the inlet can experience an alternating resistance to flow through the device; a sensor positioned within the housing and configured to detect a change in pressure within the internal chamber including the start of a flow of air through the internal chamber and a termination of a flow of air through the internal chamber; a time recorder to record a time period between a detected change in pressure within the internal chamber corresponding to the start and termination of the flow of air through the internal chamber.
15. The device as claimed in claim 14 comprising a mouthpiece releasably connectable to the inlet of the PEP therapy device, the mouthpiece comprising: a housing having an internal chamber and an inlet and an outlet to allow a flow of air through the internal chamber; wherein the sensor and the time recorder are accommodated within the mouthpiece housing.
16. The device as claimed in claims 14 or 15 further comprising a processor coupled electronically to the sensor and the time recorder.
17. The device as claimed in claim 16 wherein the processor is a microcontroller configured to control the sensor according to at least two modes of operation including a sleep mode having a first sample rate and a breath mode having a second sample rate, wherein the second sample rate is greater than the first sample rate.
18. The device as claimed in anyone of claims 14 to 17 further comprising any one or a combination of the following set of: * a battery * a non-volatile memory * a sounder * an optical output device.
19. The device as claimed in anyone of claims 16 to 18 when dependent upon claim wherein the mouthpiece housing comprises a partition extending in a direction between the inlet and outlet of the mouthpiece housing to separate the internal chamber of the mouthpiece into a passageway and a compartment, the sensor and the time recorder being accommodated within the compartment.
20. The device as claimed in anyone of claims 14 to 19 wherein the device is a hand-held airways adjunct.
21. The device as claimed in anyone of claims 14 to 19 wherein the device is a hand-held peak flow meter.