JP2011156029A - Apnea syndrome (sas) determination device by high accuracy respiratory measuring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem in that Polysomnography (PSG method) as a brain wave measurement and a fluid speed measuring apparatus are usually mounted on a nasal aperture to measure breathing and determining apnea; however, a burden is heavy on a subject in this method and it can not be used at home easily, and there is another measuring method mounted on a finger and the like for measuring the oxygen concentration in blood and measuring apnea with the change of the blood oxygen amount, but these methods impose heavy burden on the subject and the measurement can not be done if the apparatus slips. <P>SOLUTION: A noncontact biological signal detector for detecting the biological signal from biological vibration is used for measuring breathing, the biological signal of heart beat, and the body movement, and the biological signal performs AGC control for a steady value of the peak. Furthermore, for measuring the breathing stably, the body movement is detected early, and if there is the body movement, the AGC control is locked, and after the body movement is finished, it is released. It makes a stable breathing measurement possible. The device measures the apnea syndrome from the stable breath wave shape and the characteristic condition of Apnea Syndrome. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention detects a biological signal in a non-contact unconstrained manner for a subject, extracts a heartbeat signal, a respiratory signal, and a body motion signal from the signal, and determines a sleep state, apnea, and hypopnea of the subject, It relates to the device.

  In recent years, many symptoms such as sleepiness during the day due to apnea and lack of vitality during the day have been reported. Among them, snoozing driving causes social problems and may cause serious situations, and the need for treatment of apnea is increasing.

It is estimated that there are about 22.2 million people in Japan who are over 10 years old who have insomnia or insomnia. Of these, 2.22 million patients need in-hospital treatment. In addition, there are an estimated 150,000 patients with apnea.

  Apnea is defined as 30 or more apneas of 10 seconds or more during 7 hours of sleep, or 5 or more apneas or hypopneas per hour of sleep.

There are two types of respiratory loss, central nervous system abnormalities and airway obstruction with the tongue. Most of the causes of apnea are because the airways are blocked by the tongue when transitioning to a deep sleep state. This makes it difficult to get enough sleep without going into deep sleep, causing symptoms that make you feel sleepy during the day.

  To determine sleep, a polysonograph (PSG method), which is usually an electroencephalogram measurement, and a method of measuring breathing by attaching a flow velocity measurement device to the nasal outlet are generally taken, but this method has a large burden on the subject, It has been pointed out that it may be different from the normal sleep state. Other than the PSG method, a method for measuring oxygen concentration in the blood and measuring apnea based on changes in the amount of oxygen in the blood and a device for recording chest and tummy movements have been devised. Because it is restrained, the burden on the subject is large. In addition, all of the above methods have a problem that measurement cannot be performed if the subject moves greatly or the device is disconnected.

Accurate measurement of sleep and apnea conditions over a long period of time without burdening the subject is extremely important in elucidating and treating apnea and solves social problems such as snooze driving It is thought that it is effective to do. However, there is currently no device for measuring sleep and determining a sleep state or apnea state reliably for a long period of time without placing a burden on the subject.

In view of the above problems, the present invention can measure, determine and record the transition of sleep state and apnea over a long period of time without disturbing the sleep of the subject, and easily perform the sleep measurement of the subject. An object of the present invention is to provide an apnea measurement apparatus that can be used daily and can be used by subjects. In particular, an object of the present invention is to provide an apparatus that can quantitatively determine apnea and hypopnea states during sleep of a subject.

In order to achieve the above object, an apnea measurement apparatus according to the first solving means of the present invention includes a non-contact unconstrained biological signal detection means for detecting a heartbeat signal and its intensity, and variations in temporal changes in heartbeat intensity. It comprises an apnea state determination means for determining an apnea state using the (dispersion value), the intensity of the respiratory state, the amount of change, and the integral value.

According to the above solution, since the sleep state determination device determines the sleep state by detecting the heartbeat signal from the unconstrained biological signal detection means and performing arithmetic processing on the signal, the subject is not burdened. It is possible to measure the sleep state over a long period of time. In addition, since the device is not directly attached to the subject, it is possible to measure a sleep state similar to that at the time of non-measurement.

The second solving means of the present invention is the high-precision respiratory measurement apparatus of the first solving means, which measures a biological signal as vibration and measures a heartbeat signal, a respiratory signal, and a body motion signal.

The third solving means of the present invention is an apnea determination method according to the first solving means, wherein the variation in the heart rate signal intensity of the biological signal is determined to be shallow sleep, and the body motion signal is observed. When the absolute value integrated value of the area of the respiratory signal waveform is not more than a certain value and the short-time breathing signal deviation representing the amount of change is not more than a certain value, the apnea condition is determined.

The fourth solution of the present invention is the shallow sleep determination device and the determination method of the third solution, and the shallow sleep determination device includes a micro differential pressure sensor and a biological signal detection unit, and a biological signal detection unit It is characterized by detecting a change in the pressure of air contained in the inside with a slight pressure line difference, detecting a biological signal, and detecting a heartbeat signal by shaping and amplifying the signal. Therefore, it is possible to measure sleep without placing a burden on the subject's body and mind.

The shallow sleep determination method uses the heart rate signal obtained from the sleep determination device as a heart rate intensity signal, which is the reciprocal of the coefficient when the AGC control is performed. The average of the second is taken, and it is determined that the sleep is shallow when the variation is in a certain band.

The fifth solving means of the present invention is the apnea / hypopnea determining device and the determining method of the first solving means, wherein the determining device detects a biological signal using the same device as the fourth device After detecting the heart rate signal and the respiratory signal by shaping and amplifying the signal, the body movement is judged using the sudden change of the heart rate signal, and the AGC control of the respiratory signal is locked and released, and a stable respiratory signal is obtained. Since it is a biological signal detection unit having a non-restraining configuration, it is possible to measure sleep without placing a burden on the body and spirit of the subject.
The apnea / hypopnea determination method determines apnea / hypopnea when the waveform variation and the integrated value of the respiratory signal obtained from the apnea / hypopnea determination device are below a certain value for a certain period of time. It is.

The sixth solving means of the present invention is the body motion detection device and the determination method of the first solving means, wherein the determination device is similar to the fourth device, detects a biological signal, Since the heartbeat signal is detected by shaping and amplifying the signal, and the biological signal detection unit has an unconstrained configuration, it is possible to measure sleep without placing a burden on the body and spirit of the subject.

In the body motion determination method, the number of times the heart rate signal intensity is saturated due to a sudden change in signal intensity in a time shorter than the AGC control time among the heart rate signals obtained from the body motion detection device is 5 times per second. If it exceeds, it is determined as a body motion signal.

The sleep state determination device of the present invention has been confirmed to be consistent with the polysonograph (PSG method) based on electroencephalogram measurement according to the international sleep determination standard, and is guaranteed to be highly accurate.

In order to measure respiration more stably using the above device, body movement is detected at an early stage, and when there is body movement, AGC control for keeping the peak value of the biological signal at a constant value is locked, Added a function to release after completion, and invented an apnea / hypopnea determination device. Thereby, stable respiration measurement is possible.

  Using the biological signal measured by the device, it is determined that an apnea state and a hypopnea state are shallow sleep, no body movement, and a fluctuation of a respiration waveform for a certain period of time and an integrated value being a certain value or less. . Apnea is defined as 30 or more apneas of 10 seconds or more during an overnight sleep, or 5 or more apneas or similar hypopneas of 10 seconds or more during an hour of sleep It is possible to determine apnea easily by determining apnea / hypopnea using the biological signal measured by the device and illustrating the result.

Since the apparatus has a simple configuration, it has a feature that the use environment is not selected. Moreover, since the subject is not restrained, the subject's body and psychological burden are small, and the problem that the sleep state changes by performing the measurement does not occur.

The sleep state determination apparatus of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by a present Example.

FIG. 1 is an explanatory diagram for explaining the configuration of a biological signal detection means in the embodiment of the sleep stage determination device, apnea / hypopnea determination device, and body motion detection device of the present invention, and the process of determining the sleep state from the inspection signal FIG. 2 is a side view of the biological signal detection means shown in FIG. 1 as viewed from the direction of the arrow. FIG. 3 is an explanatory view showing another biological signal detection means different from the biological signal detection means shown in FIG.

FIG. 1 is a block diagram showing the configuration of the biological signal detection means of the sleep stage determination apparatus, apnea / hypopnea determination apparatus and body movement detection apparatus of the present invention and the process of determining the sleep stage from the detection means 2 is a partial cross-sectional view as seen from the direction of the arrow in FIG. The biological signal detection means 1 shown in FIG. 1 is a detection means for detecting a minute biological signal of the subject without restraining the subject, and the biological amplification is performed so that the signal can be processed in a later processing step by the signal amplification shaping means 2. The signal detected by the detection means 1 is amplified, and unnecessary signals are removed by a band pass filter or the like. Details and performance of this device are demonstrated in “Patent Publication 2003-126052” and “Patent Publication 2000-271103”.

  Sleep stage determination is determined to be shallow sleep when the average of 300 seconds of moving average for 60 seconds of variation in heart rate signal intensity obtained by means of 6 in Fig. 1 is in the range of 3-6% To do. This determination is a value that is consistent with the state of the δ wave of the electroencephalogram in the polysonograph (PSG method) based on the electroencephalogram measurement of the international sleep determination standard, and the reliability is guaranteed.

FIG. 3 is a block diagram of the body motion detection method of the present invention. The body motion is detected by using a heartbeat signal, and the detected heartbeat signal is determined by detecting a waveform different from the steady-state heartbeat signal. Although the heart rate signal is one time within about one second, when the body motion is included, the signal shows a variation different from the heart rate signal in a very short time. Since the body movement is a movement larger than the heartbeat and occurs in a very short time compared to the AGC control interval, the heartbeat signal is displayed saturated (example: FIG. 4). When the heart rate signal reaches saturation more than 5 times per second, it is determined as body movement.

FIG. 5 is a flowchart showing the apnea / hypopnea determination method of the present invention. Since the respiratory signal changes more slowly than the heartbeat, AGC control is performed once every 20 seconds. For this reason, when body movement occurs and the respiratory signal is affected, the time during which the amplification factor is reduced by AGC control is longer than that of the heartbeat signal. For this reason, even if it is not an apnea state, the state where the amplitude of the respiratory waveform is extremely small continues, and the determination is difficult.

In order to solve the difficulty in determining the respiratory waveform, if the condition 13 in FIG. 3 is satisfied, the AGC control of the respiratory signal is immediately locked, and the body movement signal is determined in 14 in FIG. The detection of the body motion signal is always performed even when the AGC control is locked, and the AGC control is adjusted so that the AGC control is canceled 120 seconds after the last body motion signal detection. Thereby, it becomes possible to detect a respiratory signal stably.

By calculating the fluctuation value for 8 seconds and the integral value for 18 seconds, the determination condition for apnea and hypopnea state is calculated. The fluctuation value of the respiratory waveform is obtained by calculating the variance (standard deviation, etc.) of the respiratory waveform value for 8 seconds. A flowchart of the calculation method of the fluctuation value is shown in 27 of FIG. If the value of this deviation is below a certain value, it can be said that the fluctuation of the waveform is small. Small fluctuations in the waveform are equivalent to apnea and hypopnea conditions. On the other hand, since the fluctuation of the amplitude of the respiratory waveform in a state close to normal breathing and awakening is very large, it is possible to distinguish apnea and hypopnea states from other states. Apnea and hypopnea are each set as a threshold value, and each state is determined when there is a value in the apnea and hypopnea ranges. The threshold is set so that normal> hypopnea> apnea. However, only the fluctuation value of the respiratory waveform affects the respiratory waveform due to body movement and snoring in the vicinity where the apnea and the hypopnea state occur, and therefore the apnea and the hypopnea state cannot be correctly determined.

In order to make a correct determination of apnea and hypopnea, the determination condition of apnea and hypopnea is calculated by performing an absolute integration operation on the respiratory waveform for 18 seconds. The flowchart of the method for calculating the integral value is shown in 28 of FIG. Since the sampling of the respiration waveform value is 20 msec, the integrated value is obtained by taking the sum of the absolute values of the values for 18 seconds. The integrated value in the apnea state is less than a certain value because there is little fluctuation. The integral value in the hypopnea state is not less than the integral value in the apnea state and not more than a certain value. Apnea and hypopnea are each set as a threshold value, and each state is determined when there is a value in the apnea and hypopnea ranges. The threshold is set so that normal> hypopnea> apnea. The integral value is not easily affected by body movement or snoring, but if the measured value is offset, the value may become large, and correct determination may not be possible only with the integral value. Considering this, it is possible to make a more accurate determination by using both the variation value and the integral value as conditions.

The determination is made using all the conditions of the body motion signal, sleep state, respiratory waveform fluctuation and integral value obtained by the calculation. First, a body motion signal is detected, and a determination is made only in a section where there is no body motion (29 in FIG. 7). Next, as indicated by 30 in FIG. 7, the determination is made only when the heartbeat intensity deviation for determining the sleep state is 3% to 6% indicating shallow sleep. Finally, as shown by 31 and 32 in FIG. 7, three types of an apnea state, a hypopnea state, and a normal state are discriminated based on the fluctuation value and the integral value of the respiratory waveform.

FIG. 5 shows an example in which the apnea state is determined based on each biological signal, apnea / hypopnea determination result, and breathing fluctuation, heart rate deviation, and breathing interval integration which are the conditions used for the determination in the embodiment of the apparatus of the present invention. It is the time series data shown. FIG. 6 is time-series data showing an example of the above data when not in an apnea state.

FIG. 5 shows an example in which each biological signal, apnea / hypopnea determination result, and respiratory fluctuation, heart rate deviation, and respiratory interval integration, which are the conditions used for the determination in the embodiment of the apparatus of the present invention, are determined to be an apnea state. It is the shown time series graph. As shown in 18 of FIG. 5, the respiratory fluctuation is below a certain value, and as shown in 19 of FIG. 5, the heart rate deviation satisfies the value determined to be a shallow sleep state, and the respiratory interval integral is a constant value. In the following cases, the determination (20 in FIG. 5) is determined to be an apnea state (17 in FIG. 5). In addition, when body movement is detected (16 in FIG. 5), the determination is not made. The apnea state continues intermittently for about 40 seconds, and the body movement occurs when the apnea state continues for a certain time. However, the sleep state continues to be a shallow sleep state, and this result is in good agreement with the phenomenon of inability to shift to deep sleep due to insomnia, followed by a shallow sleep and a feeling of not being able to sleep well. In addition, when the apnea is over, it can be observed that body movements occur in a relatively small amount of time, but this also coincides with phenomena such as taking a large breath and moving the body due to sleeplessness. It shows correctness.

FIG. 6 shows an example in which each biological signal, apnea / hypopnea determination result and respiratory fluctuation, heart rate deviation, and respiratory interval integration, which are the conditions used for the determination in the embodiment of the present invention, are determined not to be in an apnea state. It is a time series graph. Although the heart rate deviation (25 in Fig. 6) is below a certain value and is determined to be in a deep sleep state, no body motion signal (22 in Fig. 6) has been detected, Both respiratory signals are stable, consistent with deep sleep. In this state, since it is not determined that the patient is in an apnea / hypopnea state (23 in FIG. 6), the present invention can determine the apnea state, the hypopnea state, and the normal state. It is shown that.

  Apnea syndrome is a disease that causes major social problems, but the only method of testing is to attach a sensor directly to the subject. However, the contact-type examination put a great burden on the subject's body and spirit. In addition, there is a problem that the normal sleep state cannot be measured because the subject is restrained, and there is a problem that the measurement cannot be performed if the measuring device is disconnected during the sleep of the subject. Furthermore, when performing a precise inspection, it is necessary to attach a plurality of sensors, and it is impossible to carry out the inspection easily and on a daily basis.

In order to solve these problems, the present invention devised a non-invasive, non-constrained, non-contact measuring device and determination method. This measurement method not only reduces the burden on the subject, but also makes it possible to perform daily measurement, and facilitates the treatment and research of apnea syndrome. In addition, since it is only necessary to lay a device under the futon when measuring, anyone can perform inspection very easily, and the inspection efficiency and cost can be reduced.

Prior Patent Search Comparison and Views: Patent Search

JP, 2007-283030, A Sleep breathing state judging device

The difference with the present invention is that in determining the apnea state,
However, in the method of the present invention, the determination is performed using three conditions of sleep state, respiratory fluctuation, and integral value. By using three conditions, the apnea state can be accurately determined. In addition, various operations according to the present invention do not require complicated calculations and can be easily determined.

JP 2008-054759 A apnea detection device

The difference from the present invention is that in the detection of the respiratory signal,
However, the present invention is to detect a biological signal propagating through the hollow tube with a microphone. Also, In the present invention, the determination of apnea is made only by the presence or absence of a signal due to respiration, but in the present invention, the determination is made using the three conditions of fluctuation and integral value of respiration, and sleep state. However, it is different in that a low respiratory state can be detected.

JP, 2006-320734, A Sleep test device and sleep apnea test device

The difference between the present invention and the measurement method is that
In contrast to attaching an acceleration sensor to a subject, the present invention measures without restraining the subject, and the measurement method detects a biological signal vibration propagating inside a hollow tube drawn under a futon with a microphone. It is in the point to do. Also, In the present invention, the apnea state is detected only by determining the variance of the respiratory waveform. However, in the present invention, the determination is performed using the three conditions of the fluctuation of the respiratory waveform and the variance value and the sleep state. Therefore, it differs in that it is highly reliable.

It is a block diagram of the sleep state determination apparatus of this invention, a body movement detection apparatus, and an apnea / hypopnea determination apparatus. It is sectional drawing seen from the side of a biological detection means. It is a block diagram which shows the detail of a body movement detection means. It is a time series graph which compared the improvement of the respiration waveform when AGC control is locked by body motion detection compared with the case where AGC control is not locked. It is the graph which drawn the respiration waveform in the case of an apnea state, a heartbeat waveform, a determination result, a respiration fluctuation | variation, a heartbeat intensity dispersion | distribution, and a respiration integral value by time series data. 6 is a graph in which a respiration waveform, a heartbeat waveform, a determination result, a respiration variation, a heartbeat intensity variance, and a respiration integral value in a normal state are drawn as time series data. It is a flowchart explaining the step of the apnea determination method.

1.
Biological signal detection means
2.
Signal amplification shaping means
3.
Signal shaping filter
Four.
Heart rate signal detection means
Five.
Respiration signal detection means
6.
Heart rate intensity signal detection means
7.
Respiration signal fluctuation calculation
8.
Respiration signal integration calculation
9.
Body motion signal detection
Ten.
Sleep stage determination means
11.
Apnea / hypopnea status determination means
12.
Data storage output means
13.
Body motion detection conditions
14.
Body motion detection judgment
15.
Respiratory waveform
16.
Body motion signal
17.
Apnea / hypopnea status
18.
Respiration waveform fluctuation value
19.
Sleep depth judgment value
20.
Respiratory waveform integral value
twenty one.
Respiratory waveform
twenty two.
Heart rate signal
twenty three.
Apnea / hypopnea status
twenty four.
Sleep depth judgment value
twenty five.
Respiratory waveform integral value
26.
Respiration waveform fluctuation calculator
27.
Respiratory waveform integral value calculator
28.
Body motion detection judgment
29.
Sleep depth judgment
30.
Sleep state judgment by respiratory waveform fluctuation value
31.
Sleep state judgment by respiratory waveform integral value
32.
Respiratory waveform
33.
Heart rate waveform
34.
Body motion signal
35.
Respiratory waveform
36.
Body motion waveform
37.
Body motion signal

Claims (6)

  Biological vibration detection means for detecting biological vibration due to unconstrained and non-contact, biological signal detection means for detecting a biological signal from the output signal of the previous biological vibration detection means, and measurement of respiratory, heartbeat biological signal and body movement, AGC is controlled so that the peak of the biological signal becomes a constant value. Furthermore, in order to stably measure respiration, body movement is detected at an early stage. If there is body movement, AGC control is locked and released after the body movement ends. This enables stable respiration measurements. An apparatus for determining apnea from the stable respiratory waveform and the characteristics of apnea. 2. A high-accuracy respiratory measurement method and apparatus that detects body movement from the biological signal of claim 1, locks (stops) breathing AGC control, and releases the lock after the body movement ends. The apnea condition of claim 1 occurs in a shallow sleep state, and no apnea occurs during body movement, awakening, and deep sleep. Further, during normal breathing and apnea, judgment is made by taking the AND of the fluctuation value calculated by obtaining the variance (standard deviation etc.) of the breathing waveform over a certain time and the absolute integral value of the breathing waveform area. The deviation of the respiratory waveform is determined by providing a constant threshold value with normal> apnea, and the integrated value is determined with a constant threshold value with normal> apnea. The shallow sleep determination method according to claim 3 is a method and apparatus characterized in that the dispersion value of the heart rate intensity is within a certain range. The dispersion value is obtained from the dispersion value by using the reciprocal of the gain value of the AGC control as the heartbeat intensity so that the peak of the heartbeat biological signal becomes a constant value. The determination of apnea according to claim 1 includes hypopnea and apnea, and the determination requires determination of normal breath, hypopnea, and apnea. In this method, determination is made based on a fluctuation value calculated by obtaining a variance (standard deviation or the like) of a respiratory waveform over a certain period of time and an absolute integral value of the respiratory waveform area. The method and apparatus for determining the integral value by setting a certain threshold value for each of normal> hypopnea> apnea The body motion detection method according to claim 1, wherein the number of times that the biological signal strength is saturated due to a sudden change in signal strength in a time shorter than the AGC control time among the biological signals obtained by the body motion detecting means is a unit time. A method and an apparatus for determining that the signal is a body motion signal when a certain number of times is exceeded.

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