JP6389391B2 - Respiratory disorder determination device, respiratory disorder determination method and program - Google Patents

Description

  The present invention relates to a respiratory disorder determination device and the like.

  Conventionally, there has been a method for evaluating the severity of a respiratory disorder (apnea or hypopnea) during sleep. For example, a method of evaluating by using the number of apneas per hour (AI: Apnea Index) or using AHI (apnea hypopnea index) is known.

  Here, in order to accurately detect a respiratory disorder, PSG (polysomnography, polysomnography test) is used. PSG records various states such as EEG, breathing, leg movement, chin movement, eye movement (REM sleep and non-REM sleep), electrocardiogram, oxygen saturation, chest wall movement, abdominal wall movement, etc. Determine sleep state.

  However, in order to do so, it is necessary to attach many sensors to the measurement subject, which is not convenient. Therefore, an apparatus for easily determining a sleep state by detecting body movement is known.

  For example, an invention is known in which a respiratory waveform is obtained from a change in load, and an apnea state or a hypopnea state is determined based on a change in the amplitude of the respiratory waveform (for example, see Patent Document 1).

Japanese Patent No. 3823887

  In the prior art, apnea is determined based on fluctuations from the reference based on the amplitude and frequency before apnea (reference amplitude / reference frequency). However, if apnea occurs continuously, apnea occurs immediately after recovery breathing due to resumption of breathing. Therefore, it is appropriate to compare the reference breath and the recovery breath. There wasn't. In addition, body movement is often accompanied when resuming breathing, and in this case, there is a problem that the breathing amplitude and frequency cannot be measured.

  In the technique described above, even in the technique using the frequency fluctuation, the frequency fluctuation in the section where the amplitude is reduced is used for the determination. However, when the respiratory amplitude gradually decreases, the reference breathing is used. There was a problem that the difference between the amplitude and the amplitude during apnea was so small that it could not be determined as apnea.

  In view of the above-described problems, an object of the present invention is to provide a breathing disorder determination device and the like that can more appropriately detect a breathing disorder of a measurement subject by combining a plurality of detection methods. is there.

In view of the above-described problems, the respiratory disorder determination device of the present invention is
Respiration detection means for detecting respiration from the body movement of the measurement subject;
Respiration waveform calculating means for calculating a respiration waveform from the detected respiration;
A respiratory disorder determining means for determining a respiratory disorder based on the respiratory waveform;
With
The breathing disorder determination means includes
When a respiratory waveform exceeding the reference amplitude is detected or body movement is detected after 10 seconds or more have elapsed in a state where the amplitude of the respiratory waveform is within the attenuation range obtained by multiplying the reference amplitude by the attenuation threshold, First determination means for determining that there is a respiratory disorder;
A second determination means for determining that there is a respiratory disorder when the maximum value of the respiratory apex of the respiratory waveform gradually increases five times or more continuously or the minimum value of the respiratory apex gradually decreases five or more times;
Have
Even when the first determination means does not determine a respiratory disorder, if the second determination means determines a respiratory disorder, it is determined that there is a respiratory disorder.

The respiratory disorder determination method of the present invention is
A respiration detection step for detecting respiration from the body movement of the measurement subject;
A respiration waveform calculating step for calculating a respiration waveform from the detected respiration;
A respiratory disorder determination step for determining a respiratory disorder based on the respiratory waveform;
Including
The breathing disorder determination step includes
When a respiratory waveform exceeding the reference amplitude is detected or body movement is detected after 10 seconds or more have elapsed in a state where the amplitude of the respiratory waveform is within the attenuation range obtained by multiplying the reference amplitude by the attenuation threshold, A first determination step for determining that there is a respiratory disorder;
A second determination step for determining that there is a respiratory disorder when the maximum value of the respiratory apex of the respiratory waveform gradually increases five times or more continuously or the minimum value of the respiratory apex gradually decreases five or more times continuously;
Have
Even if the respiratory disorder is not determined in the first determination step, it is determined that there is a respiratory disorder when the respiratory disorder is determined in the second determination step.

  According to the present invention, when a respiratory waveform exceeding the reference amplitude is detected after 10 seconds or more have passed in a state where the amplitude of the respiratory waveform is within the attenuation range obtained by multiplying the reference amplitude by the attenuation threshold, The first determination means for determining that there is a respiratory disorder, and the maximum value of the respiratory apex of the respiratory waveform gradually increases more than 5 times or the minimum value of the respiratory apex gradually decreases more than 5 times A second determination unit that determines that there is a respiratory disorder, and if the second determination unit determines that the respiratory disorder is not determined by the first determination unit, Determine that there was a respiratory disorder. Therefore, when a respiratory disorder is determined by a plurality of determination means, the respiratory disorder is more appropriately determined.

It is a figure for demonstrating the whole in this embodiment. It is a figure for demonstrating the function structure in this embodiment. It is an operation | movement flow for demonstrating the main process in this embodiment. It is an operation | movement flow for demonstrating the 1st breathing disorder determination process in this embodiment. It is an operation | movement flow for demonstrating the 2nd breathing disorder determination process in this embodiment. It is an operation | movement flow for demonstrating the 2nd breathing disorder determination process in this embodiment. It is a figure for demonstrating the operation example in this embodiment. It is a figure for demonstrating the operation example in this embodiment. It is a scatter diagram for demonstrating the effect in this embodiment. It is a scatter diagram for demonstrating the effect in this embodiment. It is a figure of the actual respiration waveform for demonstrating the case where it determines using this embodiment. It is a figure of the actual respiration waveform for demonstrating the case where it determines using this embodiment. It is a figure of the actual respiration waveform for demonstrating the case where it determines using this embodiment. It is a figure of the actual respiration waveform for demonstrating the case where it determines using this embodiment.

  The best mode for carrying out the present invention will be described below with reference to the drawings. The following embodiment is an embodiment when the present invention is applied, and the content of the invention is of course not limited to the content of the embodiment.

[1. System appearance]
FIG. 1 is a diagram for explaining a method of using the respiratory disorder determination system. As shown in FIG. 1, the respiratory disorder determination system 1 includes a detection device 3 placed between a floor portion of a bed 10 and a mattress 20, and a processing device 5 for processing a value output from the detection device 3. It is configured with. The detection device 3 and the processing device 5 constitute a respiratory disorder determination device.

  When the subject P is present on the mattress 20, the detection device 3 detects the body movement (vibration) of the subject P via the mattress 20. Then, based on the detected vibration, the respiration of the measurement subject P is detected. In this embodiment, the detected respiration is transmitted to the processing apparatus 5 (for example, a computer etc.) via radio | wireless, and a respiration waveform can be calculated | required. For example, the detection device 3 may be integrally formed by providing a storage unit, a display unit, and the like. Moreover, since the processing apparatus 5 may be a general-purpose apparatus, the processing apparatus 5 is not limited to an information processing apparatus such as a computer, and may be configured by an apparatus such as a tab red or a smartphone.

  Here, the detection device 3 is configured in a sheet shape so as to be thin. Thereby, even if it is placed between the bed 10 and the mattress 20, it can be used without making the person to be measured P feel uncomfortable.

  In addition, the detection apparatus 3 should just be able to detect the to-be-measured person's P respiratory motion. In the present embodiment, respiration is detected based on body movement, but the body movement of the person to be measured P may be detected by an infrared sensor or the like, or an actuator with a strain gauge may be used.

[2. Functional configuration]
Next, the mechanism configuration of the respiratory disorder determination system 1 (respiratory disorder determination device) will be described with reference to FIG. The respiratory disorder determination system 1 in the present embodiment includes a detection device 3 and a processing device 5, and each functional unit (processing) can be realized by any one other than the body motion detection sensor 200. good.

  The respiratory disorder determination system 1 includes a control unit 100, a body motion detection sensor 200, an input unit 300, an output unit 400, and a storage unit 500. In the case of FIG. 1, the control unit 100, the body motion detection sensor 200, and the storage unit 500 are provided in the detection device 3, and the control unit 100, the input unit 300, the output unit 400, and the storage unit 500 are the terminal device 5. Is provided.

  The control unit 100 is a functional unit for controlling the operation of the respiratory disorder determination system 1, and is configured by a control circuit necessary for the respiratory disorder determination system 1, such as a CPU. The control unit 100 implements various processes by reading and executing various programs stored in the storage unit 500. In the present embodiment, the control unit 100 operates as a whole, but is provided in each of the detection device 3 and the processing device 5.

  The body movement detection sensor 200 is a sensor that detects the body movement of the measurement subject P. The body motion detection sensor 200 includes a respiration detection unit 210 and a body motion detection unit 220.

  The respiration detection unit 210 is a functional unit for detecting the respiration of the measurement subject. The respiration of the measurement subject is detected from the detected vibration (body motion). In addition, by using the body motion detection unit 220, body motion other than the breathing of the measurement subject P such as turning over or heartbeat can be detected.

  The respiration detection unit 210 in the present embodiment detects, for example, the vibration (body movement) of the person to be measured using a pressure sensor and detects respiration from the vibration, but the center of gravity position (body movement) of the person to be measured using a load sensor. It is good also as detecting respiration by the change of, and you may detect based on the sound which a microphone picks up by providing a microphone. It suffices if the respiration of the measurement subject can be detected using any sensor.

  The input unit 300 is a functional unit for the measurer to input various conditions and to input an operation for starting measurement. For example, it is realized by any input means such as a hardware key or a software key.

  The output unit 400 is a functional unit for outputting various respiratory waveforms and informing a respiratory disorder. The output unit 400 may be a display device such as a display, or may be a notification device (sound output device) that notifies an alarm or the like. Further, it may be an external storage device that stores data, a transmission device that transmits data through a communication path, or the like.

  The storage unit 500 is a functional unit that stores various data and programs for the breathing disorder determination system 1 to operate. The control unit 100 implements various functions by reading and executing a program stored in the storage unit 500. Here, the storage unit 500 is configured by, for example, a semiconductor memory, a magnetic disk device, or the like.

  Here, the storage unit 500 stores a respiratory wave detection program 502, a reference amplitude calculation program 504, a main program 506, a first respiratory disorder determination program 508, and a second respiratory disorder determination program 510. .

  The respiration wave detection program is a program that is always executed in the background when the main program 506 is executed, and detects and outputs a respiration wave based on respiration detected from the respiration detection unit 210.

  The reference amplitude calculation program 504 is a program that calculates a reference amplitude (reference amplitude) among respiratory amplitudes at a predetermined timing. For example, the reference amplitude is calculated by calculating an average from three breathing amplitudes.

  The main program 506 is a program executed mainly in the present embodiment. In the step of the main program 506, a first respiratory disorder determination program 508 and a second respiratory disorder determination program 510 are executed.

[3. Process flow]
Subsequently, a flow of processing (main processing) of the respiratory disorder determination system 1 in the present embodiment will be described.

[3.1 Main processing]
First, the main process in this embodiment will be described with reference to FIG. This sleep evaluation process is a process executed when an operation instruction to be measured is performed by the measurer when the person to be measured enters a sleep state.

  First, body motion is detected (step S102), and a respiratory waveform is calculated based on the body motion (step S104). The respiration waveform is calculated by executing the respiration wave detection program 502 based on the respiration detected by the body motion detection sensor 200 (respiration detection unit 210).

  Further, the reference amplitude is calculated by executing the reference amplitude calculation program 504. The reference amplitude is calculated from the respiratory waveform in a normal state as an average respiratory amplitude (for example, an average of respiratory amplitudes for two to three breaths) as a reference amplitude. The reference amplitude may be obtained from the calculated respiratory waveform, or a value corresponding to the age or physique is previously obtained, and the value may be used.

  Here, the first breathing disorder determination process (step S106) and the second breathing disorder determination process (step S108) are performed while this process is being performed. A respiratory disorder is detected based on any respiratory disorder determination process.

  Here, the first respiratory disorder determination process and the second respiratory disorder determination process may be executed in parallel, or may be executed as needed. For example, the second breathing disorder determination process may be executed only when the breathing disorder is not determined in the first breathing disorder determination process.

  And this process is repeatedly performed until a measurement is complete | finished (step S110; No-> step S102).

  Here, the first respiratory disorder determination process executed in step S106 and the second respiratory disorder determination process executed in step S108 will be described in detail.

[3.2 First Breathing Disorder Determination Process]
The first breathing disorder determination process will be described with reference to FIG. First, it is determined whether or not the currently calculated respiratory waveform has entered the attenuation range (step S202). Here, the attenuation range is a range in which the reference amplitude is multiplied by a predetermined attenuation threshold, and is approximately 30 to 50% or more attenuated from the reference amplitude. For example, in the present embodiment, if the attenuation threshold is 0.5, it is determined whether or not the respiratory amplitude is within 50% of the reference amplitude.

  When the respiratory waveform once enters the attenuation range and then the respiratory waveform exceeds the attenuation range again (step S202; Yes → Step S204; Yes), the time during which the respiratory waveform has entered the attenuation range is the decay time. It is determined whether or not this is the case (step S206). The decay time is a predetermined threshold value, and is set as 10 seconds in this embodiment.

  If the reference amplitude is exceeded within 1 to 3 breaths after the respiratory amplitude is within the attenuation range for the decay time or longer (step S208; Yes), it is determined as a respiratory disorder event (step S212).

  On the other hand, the respiratory waveform does not exceed the reference amplitude within 1 to 3 breaths, but also when a body motion is detected (Step S208; No → Step S210; Yes), a respiratory disorder event is determined (Step S212).

  If these conditions are not met, the respiratory disorder event is not determined in the first respiratory disorder determination process (Step S208; No → Step S210; No, Step S206; No).

  Moreover, in embodiment mentioned above, in step S208, S210, although demonstrated within 1-3 respiration, you may detect with time. For example, it may be determined as a respiratory disorder event when the reference amplitude is exceeded or body motion is detected within 5 seconds.

[3.3 Second Breathing Disorder Determination Process]
The second breathing disorder determination process will be described with reference to the drawings. FIG. 5 is a diagram for explaining this process.

  First, initialization is performed with a variable n = 1 (step S302), and a change in respiratory amplitude is determined. For example, as an example, the apex of the respiration waveform (respiration apex) is calculated (step S304). The apex of the respiration waveform (respiration apex) may be the maximum value portion (mountain portion) of the respiration waveform and the minimum value portion (valley portion) of the respiration waveform.

  Here, using the largest part (mountain part) and the smallest part (valley part) has the same essential effect regardless of which is used. Therefore, for the convenience of explanation, even if the maximum portion (mountain portion) is described, it goes without saying that those skilled in the art can realize the same processing for the minimum portion (valley portion).

  Subsequently, it is determined whether or not the respiratory apex gradually increases (in the case of a mountain) (step S306). In addition, when determining in the case of the valley part, it is determined whether it is decreasing gradually. Specifically, the gradual increase (gradual decrease) is determined by comparing the current respiratory apex with the previous respiratory apex. As a result, it is determined whether or not the amplitude of the respiratory waveform is gradually increasing (gradually decreasing).

  Since it is desired to determine that the amplitude of the respiration waveform is gradually increasing, it is also possible to determine not the apex but another portion and determine that the amplitude is gradually increasing based on that portion.

  If the breathing apex is gradually increasing (gradually decreasing) (step S306; Yes), it is determined whether the next respiratory apex is gradually increasing (gradually decreasing) as well. That is, n is incremented (1 is added to n) (step S308), and determination is continued while n is smaller than 5 (step S310; No → step S304).

  Next, when n becomes 5 or more, the breathing apex has gradually increased (gradually decreased) by 5 or more (step S310; Yes), so it is determined as a respiratory disorder event. However, in this case, if there is a value of 50% or more of the total increase (gradual decrease) of the single respiratory apex detected so far, it is determined that there is no respiratory disorder (exclusion requirement) (step S312; No. ).

  When it does not correspond to the said exclusion requirement (step S312; Yes), a respiratory disorder event is determined (step S314).

  It was discovered that the respiratory motion waveform used for the second respiratory disorder determination process is frequently observed during recovery breathing when apnea occurs continuously or when the respiratory amplitude gradually decreases. According to the second breathing disorder determination process, since the reference amplitude is not necessary, it is possible to solve the problems of the conventional technology.

  Here, the second breathing disorder determination process will be described with reference to FIG. FIG. 6 illustrates the process of FIG. 5 more specifically. Of course, it is also possible to determine a respiratory disorder from the gradual decrease of the respiratory apex by reversing the added value or the like.

  First, variables are initialized (step S402). In the present embodiment, i = 1 and the values of the arrays b, c, and sum are set to 0. Here, the maximum value is assigned to the array b, the increase / decrease value is assigned to the array c, and the total increase / decrease value is assigned to sum. I is a counter.

  Subsequently, a respiratory waveform is calculated (step S404). Here, the maximum value is substituted into b (i) as the apex of the respiratory waveform (step S406). Here, if i is 1, 1 is added to i (incremented) (step S408; Yes-> step S412), and the processing is repeated from step S404.

  In step S408, when i is other than 1, the value of b (i) -b (i-1), that is, the difference between the maximum values is substituted for c (i) (step S408; No-> step S410).

  Here, when c (i) is 0 or less, the maximum value does not increase gradually. Therefore, the variable is initialized again and the process is repeatedly executed (step S414; No → step S402).

  When c (i) is larger than 0, the value of c (i) is added to sum (step S416), and i is incremented (step S418). Here, the process is repeatedly executed until i exceeds 5, that is, until the local maximum value gradually increases five times (step S420; No → step S404).

  When i exceeds 5 (step S420; Yes), the counter i is once initialized with 2 (step S422), and it is determined whether c (i) is less than 50% of the total value sum (step S424). Here, when c (i) is 50% or more of the total value sum (step S424; No), the process is executed again from step S402.

  When all of the difference values c (2) to c (5) are less than 50% of the total value sum (step S424; Yes → Step S426 → Step S428; Yes), a respiratory disorder event is determined ( Step S430).

[4. Example of operation]
Subsequently, the operation in the present embodiment will be described with reference to the drawings. 7 and 8 are diagrams schematically showing a respiratory waveform. When the reference amplitude is M1, there is a time t1 when the amplitude of the respiratory waveform is in the attenuation range M2. This time t1 is 10 seconds or more, and then the amplitude of the respiratory waveform exceeds the attenuation range M2 during the time t2.

  And during time t2 (within 3 breaths), the amplitude of the respiratory waveform exceeds the reference amplitude. Therefore, in FIG. 7, a respiratory disorder event is determined by the first respiratory disorder determination process.

  In the schematic diagram of FIG. 8, a respiratory disorder event is not detected in relation to the reference amplitude or the attenuation range. However, during the time t3 starting from the maximum point P1, the values of the points P2, P3, P4, P5 and the giant point gradually increase. Thereby, the respiratory disorder event is determined by the second respiratory disorder determination process.

  Actually, the correlation in which the current respiratory disorder event, for example, an apnea state is detected is shown in FIGS. The vertical axis represents the number of respiratory disorder events detected using PSG, and the horizontal axis represents the number detected using only the body motion detection sensor. FIG. 9 shows a case where it is detected only that 10 seconds have passed since the amplitude of the respiratory waveform entered the attenuation range, and FIG. 10 is a diagram describing the correlation by the determination method based on this embodiment.

  9 and FIG. 10 are compared. When regression analysis is performed based on the scatter diagram of FIG. 9, the correlation coefficient is obtained as “0.58”. Further, when regression analysis is performed based on the scatter diagram of FIG. 10, the correlation coefficient is obtained as “0.75”. Thus, it can be seen from the obtained correlation function (correlation coefficient) that a respiratory disorder event (such as an apnea condition) is determined in a more accurate state in this embodiment.

  11 to 14 show actual measurement data. In FIG. 11, since the amplitude of the respiratory waveform exceeds the reference amplitude after entering the attenuation range, it can be determined that the shaded portion is a respiratory disorder (apnea).

  However, in the case shown in FIG. 12, if it is determined that the respiratory waveform is within the attenuation range as a respiratory disorder, the shaded part is determined as a respiratory disorder. In the case of the present embodiment, since the respiratory waveform exceeding the reference amplitude is not detected after entering the attenuation range, it is not erroneously determined that there is a respiratory disorder.

  FIG. 13 is a respiratory waveform when apnea occurs continuously. Here, a partially enlarged view is shown in FIG. Since apnea occurs immediately after recovery breathing, the reference amplitude cannot be obtained, and conventionally, it is not determined as a respiratory disorder. However, according to the second disordered breathing determination process, it is possible to determine a disordered breathing when breathing movement is increased because oxygen is taken in during airway obstruction.

[5. Modified example]
The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and the design and the like within the scope of the present invention are also within the scope of the claims. include.

  Note that the detection device 3 in the above-described embodiment may be simply placed on the mattress 20 to detect the body movement of the measurement subject P. In this case, although the detection accuracy is reduced, the system can be simply realized by using, for example, a smartphone.

  Further, in the second breathing disorder determination process in the present embodiment, it is determined whether or not the value that gradually increases (gradually decreases) is 5, but may be more than that. For example, when five or more are detected, the determination may be continued while the respiratory apex is gradually increasing (gradually decreasing).

DESCRIPTION OF SYMBOLS 1 Respiratory disorder determination system 3 Detection apparatus 5 Processing apparatus 10 Bed 20 Mattress 100 Control part 200 Body movement detection sensor 210 Respiration detection part 220 Body movement detection part 300 Input part 400 Output part 500 Storage part 502 Respiration wave detection program 504 Reference amplitude calculation Program 506 Main program 508 First respiratory disorder determination program 510 Second respiratory disorder determination program

Claims (4)

Respiration detection means for detecting respiration from the body movement of the measurement subject;
Respiration waveform calculating means for calculating a respiration waveform from the detected respiration;
A respiratory disorder determining means for determining a respiratory disorder based on the respiratory waveform;
With
The breathing disorder determination means includes
When a respiratory waveform exceeding the reference amplitude is detected or body movement is detected after 10 seconds or more have elapsed in a state where the amplitude of the respiratory waveform is within the attenuation range obtained by multiplying the reference amplitude by the attenuation threshold, First determination means for determining that there is a respiratory disorder;
A second determination means for determining that there is a respiratory disorder when the maximum value of the respiratory apex of the respiratory waveform gradually increases five times or more continuously or the minimum value of the respiratory apex gradually decreases five or more times;
Have
A respiratory disorder determination device, wherein even if a respiratory disorder is not determined by the first determination unit, it is determined that there is a respiratory disorder when the respiratory disorder is determined by the second determination unit.   2. The respiration according to claim 1, wherein the second determination means has a value of less than 50% of the total change in the respiratory apex among the gradually increased value or gradually decreased value of the respiratory apex. Fault determination device. A respiratory disorder determination method performed by a respiratory disorder determination device,
The breathing disorder determination device,
A respiration detection step for detecting respiration from the body movement of the measurement subject;
A respiration waveform calculating step of calculating a respiration waveform from the detected respiration;
A breathing disorder determination step of determining a respiratory disorder based on the respiratory waveform;
And
The breathing disorder determination step includes
When a respiratory waveform exceeding the reference amplitude is detected or body movement is detected after 10 seconds or more have elapsed in a state where the amplitude of the respiratory waveform is within the attenuation range obtained by multiplying the reference amplitude by the attenuation threshold, A first determination step for determining that there is a respiratory disorder;
A second determination step of determining that there is a respiratory disorder when the maximum value of the breathing peak of the breathing waveform gradually increases five times or more continuously or the minimum value of the breathing peak gradually decreases five or more times continuously;
Have
A respiratory disorder determination method, wherein even if a respiratory disorder is not determined in the first determination step, it is determined that there is a respiratory disorder when the respiratory disorder is determined in the second determination step . A respiration detection step for detecting respiration from the body movement of the measurement subject;
A respiration waveform calculating step for calculating a respiration waveform from the detected respiration;
A respiratory disorder determination step for determining a respiratory disorder based on the respiratory waveform;
A program for causing a computer to execute
The breathing disorder determination step includes
When a respiratory waveform exceeding the reference amplitude is detected or body movement is detected after 10 seconds or more have elapsed in a state where the amplitude of the respiratory waveform is within the attenuation range obtained by multiplying the reference amplitude by the attenuation threshold, A first determination step for determining that there is a respiratory disorder;
A second determination step for determining that there is a respiratory disorder when the maximum value of the respiratory apex of the respiratory waveform gradually increases five times or more continuously or the minimum value of the respiratory apex gradually decreases five or more times continuously;
Have
A program characterized by determining that there is a respiratory disorder when a respiratory disorder is determined by the second determination step even when a respiratory disorder is not determined by the first determination step.