ORAL DEVICE FOR MEASURING RESPIRATORY SOUNDS

Abstract

The invention relates to a thermometer-shaped oral device for measuring respiratory sounds. The oral device comprises a mouthpiece with a metallic tip for placement under the tongue and a neck around which the lips seal the mouth closed, preventing outside noises from interfering with the measurement of the respiratory sounds. The oral device performs the auscultatory function traditionally performed by a stethoscope. The metallic tip may contain a thermistor for oral temperature measurement, and in various embodiments the oral device may further comprise other vital signs sensors. The oral device may be in communication with a cloud server, as part of a system for remote auscultation by a physician and/or analysis of auscultation and/or other vital signs by a healthcare bot for detecting progression of respiratory or other diseases.

Claims

1.-14. (canceled)

15. An oral device for recording respiratory sounds and oral temperature, comprising a handle section and a mouthpiece, said mouthpiece comprising a neck and a tip; said neck is configured for the lips of a subject to be wrapped around thereby sealing the mouth of said subject closed during placement of said tip inside the mouth of said subject; said tip further comprises a temperature sensor for sensing oral temperature of said subject; wherein said mouthpiece further comprises one or more microphones, configured to be disposed inside said mouth and detect respiratory sounds from oronasal cavity and/or the lungs of said subject during said placement.

16. The oral device of claim 15, further comprising a display.

17. The oral device of claim 16, further configured to calculate the respiratory rate of said patient from said respiratory sounds, wherein said display is configured to display said respiratory rate and/or said oral temperature of said subject.

18. The oral device of claim 15, further comprising sensors selected from a group consisting of an ECG, a pulse-oximetry sensor, or any combination thereof.

19. The oral device of claim 18, wherein said display is further configured to display pulse rate and/or SpO.sub.2 of said subject, measured by said pulse oximetry sensor.

20. A system comprising the oral device of claim 15, further comprising a cloud server in wireless communicative connection with said oral device; wherein said cloud server is configured to upload and store one or more of said sensed data comprising said lung auscultation; and said cloud server is in communicative connection with a display device of medical personnel.

21. The system of claim 20, further configured for measuring lung auscultation from a location of said medical personnel's display device remotely disposed from said oral device.

22. The system of claim 20, wherein said wireless communicative connection comprises a 5G modem, a SIM module, Bluetooth/BLE, WiFi, cellular, or any combination thereof of said oral device.

23. The system of claim 21, wherein said cloud server is further configured to analyze and monitor trends of said lung auscultation for evidence of progression of a disease.

24. The system of claim 21, further configured for said display to display the auscultation, its analysis, or any combination thereof on said display device.

25. The system of claim 23, wherein said analysis comprises the ratio of time that the breathing also includes a wheeze measurement and/or a count of crackles during breathing.

26. The system of claim 25, wherein said count of crackles comprises a number of crackles during the early or late inspiratory phases, number of crackles during the early or late expiratory phase, total number of crackles, or any combination thereof.

27. A method for recording respiratory sounds, comprising steps of inserting said oral device into the subject mouth said device having a handle section and a mouthpiece, said mouthpiece comprising a neck and a tip; wrapping the lips of a subject around said neck sealing the mouth of said subject closed during placement of said tip inside the mouth of said subject such that the oral temperature sensor of said tip is under the tongue, said subjects lips are closed around the said device neck oral temperature sensing tip of said subject; and said one or more microphones of said mouthpiece are inside said mouth during said placement; said microphones detecting respiratory sounds from said oronasal cavity and/or said lungs during said placement.

28. The method of claim 27, further comprising one or more steps of calculating the respiratory rate of said subject from said respiratory sounds and displaying said respiratory rate and/or said oral temperature of said subject.

29. The method of claim 28 further comprising a step of providing said oral device with an ECG, pulse oximetry sensor, or any combination thereof.

30. The method of claim 29, further comprising a step of displaying the pulse rate and/or the SpO.sub.2 of said subject measured by said pulse oximetry sensor.

31. The method of claim 27, comprising steps wherein said oral device is communicatively connecting to a cloud server; said cloud server uploading and storing data comprising said respiratory sounds; and communicatively connecting said cloud server with a display device of medical personnel.

32. The method of claim 31, further comprising a step of configuring said system for lung auscultation from a location of said medical personnel's display device remotely disposed from said oral device.

33. The method of claim 31, further comprising a step of selecting said communicative connection from said oral device from a 5G modem, a SIM module, Bluetooth/BLE, WiFi, cellular, a USB, or any combination thereof of said oral device.

34. The method of claim 33, further comprising steps of said cloud server analyzing and monitoring trends of said lung auscultation for evidence of progression of a disease.

35. The method of claim 33, further comprising a step of said display displaying the auscultation, its analysis, or any combination thereof.

36. The method of claim 35, wherein said analysis comprises the ratio of time that the breathing also includes a wheeze measurement and/or a count of crackles during breathing.

37. The method of claim 36, wherein said count of crackles comprises a number of crackles during the early or late inspiratory phase, number of crackles during the early or late expiratory phase, total number of crackles, or any combination thereof.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0028] FIG. 1 provides a view of exemplary embodiments of a thermometer-shaped device, as defined in the present disclosure.

[0029] FIG. 2 provides a view of an oral device for detecting respiratory and/or lung sounds, according to some embodiments of the invention.

[0030] FIGS. 3A and 3B show external exploded and assembled views, respectively, of the mouthpiece of the oral device, according to some embodiments of the invention.

[0031] FIGS. 4A and 4B show internal exploded and assembled views, respectively, of the mouthpiece, according to some embodiments of the invention.

[0032] FIG. 5 shows a functional block diagram a control circuit of the oral device, according to some embodiments of the invention.

[0033] FIG. 6 shows a schematic view of the entire respiratory system, from the oronasal cavity, through the trachea, and to the lungs.

[0034] FIG. 7 shows an example of a waveform of the sounds generated by the respiratory system.

[0035] FIG. 8 shows a functional block diagram of a system for remote measurement of lung auscultation and/or other vital signs.

[0036] FIGS. 9A-9D show experimental waveforms received from the oral device according to different filtering and noise reduction conditions.

DETAILED DESCRIPTION OF EMBODIMENTS

[0037] Definition: As exemplified in FIG. 1, a “thermometer-shaped device” 1 comprises a handle section 2 and a mouthpiece comprising a neck 3 and a tip 4. The tip 4 is configured for placement under the tongue and the neck 3 is configured for being wrapped around and sealed by the lips.

[0038] Reference is now made to FIG. 2, showing a preferred embodiment of the device 5 of the present invention. The device 5 comprises a handle section 19 and a mouthpiece 20. The mouthpiece 20 contains an assembly for the detection and recording of respiratory and lung sounds when it is placed in the patient's mouth. When the tip 10 of the mouthpiece 20 is placed under the patient's tongue, the patient's lips close around a neck 11 of the mouthpiece 20, creating a sound ox reaching from the lungs to the oronasal cavity, via the trachea. Thus, the action of placing the device in the mouth enables the detection of respiratory and lung sounds to take place. In some embodiments, the tip 10 contains a thermistor for taking of the patient's temperature. Suitable thermistors for the oral temperature-sensing include the MF51E2252F3950C bead type thermistor from Cantherm (Montreal, Canada).

[0039] In some embodiments, the oral device 5 further comprises an ECG and/or pulse oximetry sensor, wherein the handle section 19 comprises two grasping points 12, 13 for holding the device, a display 14, an activation button 15, two electrode contacts 16, 17 and a pulse-oximetry sensor 18. Located within the device is an internal electronics board (PCB) containing a control circuit 50 whose block diagram is shown in FIG. 5. The control circuit 50 processes the signals measured from the various sensors and optionally transmits all or part of the signals data to an external device such as a smartphone (not shown).

[0040] Reference is now made to FIGS. 3A and 3B, showing external exploded and assembled views, respectively, of the mouthpiece 20, according to some embodiments of the invention; as well as FIGS. 4A and 4B, showing internal exploded and assembled views, respectively, of the mouthpiece 20, according to some embodiments of the invention. The mouthpiece 10 contains one or more in-mouth microphones 33 and 34, for listening to respiratory sounds. When the mouthpiece 20 is inserted into the mouth, the tip 10 is placed under the tongue and the lips rest against the neck 11. When the lips are thus sealed around the mouthpiece 20 of the oral device 5, acoustic access holes 21 and 22 are located within the mouth and thus exposed to the sounds detectable therein.

[0041] Acoustic access holes 21, 22 can be slightly recessed, such that there is a place to insert a disc of an air/liquid filter material 30 and 31, where the microphones 33, 34 are mounted inside the mouthpiece on the other side of the holes 21, 22. This arrangement prevents the entry of liquid into the microphones, while ensuring that the microphones are able to pick up the sounds detectable within the oral cavity. It is possible to use a plurality of microphones for this purpose, with the sounds analyzed potentially representing the sum (or some other function) of the sounds detected by the microphones. One advantage of using two microphones is that, in the event that one gives a clear signal and the other seems blocked—for example by the tongue—then the stronger signal can be used. Suitable potential microphones for this purpose include digital microphones like the MP34DTO6J PDM-type microphone from STMicroelectronics NV (Eindhoven, Holland); and sensitive analog microphones such as the CMC-4015-25L100 electret condenser microphone from CUI Devices (Lake Oswego, OR, USA). An example of a suitable material for the air/liquid filters 30, 31 are hydrophobic membranes from W. L. Gore & Associates, Inc. (Newark, Del., USA).

[0042] Reference is now made to FIG. 5, showing a functional block diagram of the control circuit 50 of the oral device 5, according to some embodiments of the invention. In preferred embodiments, the microphones 33, 34 are digital, such that they can be interfaced directly into the bus of the processor 52. For this preferred embodiment, an example processor 52 is the Cypress BLE microprocessor module CYBLE-416045-02 from Cypress Semiconductor Corp. (San Jose, Calif., USA) may be used. Advantageously, the Cypress processor contains an integrated Bluetooth Low-Energy (BLE) module, thereby obviating the need to incorporate a separate communications chip 58 in the control circuit 50. Advantageously, the thermistor(s) described above can also be connected directly to the Cypress processor, using its internal A/D conversion channels.

[0043] The ECG electrodes 16, 17 on the body 19 of the device are interfaced to an ECG chip 54, which is interfaced digitally into the microprocessor 52. In a preferred embodiment of the circuit, a single chip contains both the ECG module 54 and the pulse-oximetry module 56, of which the sensor 18 is a part. An example integrated sensor chip of this type is the MAX86150 chip from Maxim Integrated (San Jose, Calif., USA). Advantageously, by building the circuit around just two main chips—an integrated microprocessor plus BLE module and an integrated sensor chip—the complexity is reduced while the costs are minimized. Suitable displays for the device of the present invention include LCDs and LEDs, for example the 1.44″ graphical TFT-type LCD display model KSF128128A0-1.44, from KSF Ltd. (Hong Kong).

[0044] Operation of the device of the present invention to detect and record respiratory and lung sounds, in preferred embodiments, proceeds as follows. After activating the device using its switch, the patient grasps the device, preferably using the grasping positions 12 and 13, and places the mouthpiece in his mouth such that the oral-temperature tip is under his/her tongue and his/her lips are closed around the neck 11. It is recommended to use the grasping positions such that a finger rests in the recess while the opposable thumb presses against the underside of the device at that place. After approximately 20-30 seconds, the device issues a beep and/or an indication on the display 14, to signal that the “temperature reading” is complete. Note that, due to the thermometer-type design of the device, the measurements taken during this time include (as a minimum) both oral temperature and a recording of the sounds detected within the mouth by the microphone during this period. A digital recording of these sounds, at the resolution and sampling rate chosen (for example 12 bits at 4 kHz), is stored in the memory 66 of the control circuit 50 and/or transmitted via the communications module to a computer or smartphone (not shown), or uploaded to the internet (for example over WiFi). In preferred embodiments, the data is transmitted over BLE to a smartphone for recording and uploading to a remote computer system. This configuration enables a remote physician to listen to the sounds recorded and analyze them. As physicians typically perform auscultation for only a few seconds at any given body location, it will typically be sufficient to record and forward between 5 and 10 seconds of the sound recording taken by the device of the present invention.

[0045] Reference is now made to FIG. 6. The respiratory system extends from the oronasal cavity 70, down through the trachea 72 to the lungs 74. Also shown is the internal structure 76 of the lungs. Advantageously, as the microphones 33, 34 are located within the respiratory system, it is possible to detect the respiratory sounds within the entire respiratory system. Additionally, and synergistically with the standard use of a thermometer, the mouth is kept closed by the patient for the duration of the temperature reading, thereby increasing the degree to which the respiratory and lung sounds are trapped within a mostly closed space and external interference is reduced. A key advantage of the present invention is that this sound detection is performed internally within the body, as opposed to requiring an external membrane interface external to the body (as is the case 215 when a stethoscope is used). In this manner, the present invention serves to enable the functional equivalent of lung auscultation to be performed, but without the use of a stethoscope.

[0046] Reference is now made to FIG. 7, showing a typical waveform 77 of lung sounds detected by chest auscultation of a single respiratory cycle, taken by a conventional digital stethoscope. (In the Experimental section below, the digital stethoscope waveform 77 shall be compared with waveforms from the oral device 5.) The waveform is overlaid by an air flow plot 78 (inspirium/experium) detected at the mouth. It is noted that there is a low-frequency periodicity associated with the breathing action (typically 10-15 breaths/min in an adult), and higher-frequency lung sounds are detectable during both the inhalation and expiration phases of each breath.

[0047] The low-frequency wave shown is isolated in order to calculate the patient's respiratory rate and I:E ratio. Respiratory rate is an important vital sign, and so, in a preferred embodiment, this rate is calculated within the control circuit 50 of the device and displayed on its internal display 14.

[0048] The oral device 5 shown in FIG. 1, measures and displays the respiratory rate and the oral-temperature. In some embodiments, additional sensors detect and enable display of further medical parameters. A pulse-oximetry sensor 18 can be located along a finger grasping location (either 12 or 13). In this configuration, when the patient grasps the oral device 5 as instructed, his/her pulse rate and oxygen saturation (SpO.sub.2) parameters will be measured by the pulse-oximeter while the temperature reading is underway. In a preferred embodiment, these data are also be shown on the display 14 of the device; such that it is possible to display the four vital signs: temperature, respiratory rate, pulse rate and SpO.sub.2 on the display. The vital signs may either be displayed simultaneously or, for example, by using a switch 15 to toggle between showing the different parameters.

[0049] Similarly, during the time that the patient is holding the device in his/her mouth to perform the temperature measurement, if the patient is holding the device as instructed, with a finger of each hand in the grasping places 12, 13, then the electrodes 16, 17, located in the grasping areas 12, 13 enable an ECG reading to be taken at the same time. The electrodes 16, 17 are connected to the ECG chip 54 described in conjunction with the block diagram shown in FIG. 4. In some embodiments, an additional third electrode is applied at the mouth, either via a metallic section 23 on the mouthpiece 20, or by using the metallic tip 10 which houses the temperature sensor. Where a three-electrode configuration is used—one on each finger and one in the mouth—the ECG trace generated may be calculated according to the description given in co-pending patent PCT/IL2020/050874.

[0050] Thus, by proper use of an oral device 5 of the present invention, a large number of medical parameters may be measured simultaneously. Any or all of this information may be transmitted via the communications module to a remote computer, via a smartphone or any other suitable means.

[0051] The lung sounds detected by an oral device 5 of the present invention can serve to diagnose respiratory conditions and enable the progression of respiratory disease to be monitored. As described above, typical lung sounds associated with specific respiratory conditions include different types of wheezes, crackles, or combinations thereof which can serve to characterize asthma, COPD, bronchiolitis, cystic fibrosis and PAH. For example, asthma is typically identified by the combination of early inspiratory crackles and late inspiratory fine crackles, whereas bronchiectasis can be identified by wet crackles. Similarly, the combination of a mid-inspiratory wheeze and a mid-expiratory wheeze suggests bronchiolar disease.

[0052] In a similar manner, specific heart sounds detected via the device can also be indicative of cardiac conditions, and their worsening can indicate deterioration.

[0053] Reference is now made to FIG. 8, showing a functional block diagram of a system 80 for remote measurement of lung auscultation and/or other vital signs. The oral device 5 digitally samples the lung sounds and transmits the sampled data wirelessly to a cloud server 90. For example, the data may be transmitted from the oral device 5 by a SIM module or 5G modem 82; or, for example, by Bluetooth/BLE 84 to a smartphone 86 and then via WiFi or cellular 88 from the smartphone 86 to the cloud server 90. The cloud server 90 uploads and stores the sampled data, for transmission to a physician or computer analysis, as further described herein. Alternatively, some or all analysis may be performed within the control circuit 50 and/or the smartphone 86. The control circuit 50, smartphone 86, or cloud server 90 may timestamp the sampled data.

[0054] A display device 92, connected to the cloud server 90, of medical personnel 94 can display the auscultation waveform to the medical personnel 94 for remotely monitoring a patient. Alternatively, or in addition, a healthcare bot can monitor and analyze changes in the sounds over time. For example, a healthcare bot within or accessible to the cloud server 90 may analyze an auscultation waveform of a patient over time for indications of disease progression. In particular, numerical indices of wheezes and crackles can be generated by isolating these sounds from the sound recording, and the trends of these indices can be observed. For example, an index of T.sub.wheeze/T.sub.total showing the ratio of time that the breathing also includes a wheeze component can be recorded and followed, where a rise in this ratio shows a trend towards a worsening condition. Similarly, “crackles” can be detected and a count of “crackles” maintained, preferably organized according to the breathing phase, such that the number of crackles during the early/late inspiratory phase and during the early/late expiratory phase of the breathing is known, in addition to the total number of crackles. All three of these indices can be monitored for trends, where an increase in the crackle count signifies a deterioration in the condition of the lungs. Early inspiratory and expiratory crackles are the hallmark of chronic bronchitis, whereas late inspiratory crackles may mean pneumonia, CHF, or atelectasis.

[0055] These potential problems can then be signaled as alerts to medical personnel 94, caretakers, and/or patients. Such a remote analytics system and method can also factor in additional physiological data (such as ECG and vital signs) and their trends, whether this additional data is collected by the device 5 or other devices.

EXPERIMENTAL DATA

[0056] On placement of the device into the mouth and sealing of the lips around it, the microphone was located within the oronasal cavity. The raw sound waveform for several respiratory cycles is shown in FIG. 9A. The high frequency whistling and noise present within the oronasal cavity serve to obscure the underlying sound pattern. However, by applying a high-pass filter set at 1000 Hz to this data, with a roll-off of 6 dB/octave, the received data shown in FIG. 9B clearly shows a typical inspirium and experium pattern as would be heard by applying a stethoscope to the chest.

[0057] In order to determine the relative importance of the noise reduction, we applied a 16 dB noise reduction with a sensitivity of 6.0, using 3 frequency smoothing bands, with the results being shown in FIG. 9C. We then applied the high-pass filter used above (i.e. 1000 Hz, with a roll-off of 6 dB/octave) to the noise-reduced data, in order to yield the sound wave shown in FIG. 9D.

[0058] As is readily appreciated, the signal processing enables the production of an ausculation-type sound wave which is significantly equivalent to that yielded by the use of a stethoscope against the chest in traditional auscultation.

[0059] Comparing the experimentally-derived waveforms in FIGS. 9B and 9D to a standard “textbook” illustration of the components of a chest auscultation, as shown in FIG. 7, it is clear that the major components—inspirium, experium, and lung sounds—are all present in the sound wave data, as detected and then processed by an oral device 5 of the current invention.

[0060] The oral device 5 enables a physician to perform remote auscultation, by receiving and listening to the sound data file at a remote location. Advantageously, this system enables the performance of remote auscultation to be performed without the traditional requirement for the patient to place an electronic stethoscope on his chest. Essentially, the patient just needs to “take his temperature” and the process of recording, signal-processing and transmission of the data is performed automatically.