JP6013153B2 - Respiratory function testing device - Google Patents

Description

  The present invention relates to a respiratory function test apparatus that measures forced vital capacity.

  In general, the examination of forced vital capacity is particularly important among respiratory function tests. The forced vital capacity is the difference in capacity between the maximum inspiratory position and the maximum expiratory position when the maximum inspiratory position is reached and the maximum expiratory position is reached. For example, in the spirometer of Patent Document 1, when an effort call is started from the maximum inspiratory position, it is possible to accurately measure the forced vital capacity by urging the subject to continue the expiration until the end of expiration is confirmed. Yes.

JP 2007-229101 A

  However, when the lung function of the subject is reduced due to a disease or the like, it is a heavy burden on the subject to continue exhalation until the end of expiration, which is also a factor that hinders the measurement of forced vital capacity.

  The present invention has been made based on such a background, and an object of the present invention is to provide a respiratory function test apparatus that reduces the burden on the subject at the time of forced vital capacity measurement.

  In order to solve the above problems, the following measures were taken. The reference numerals used in the description of the best mode for carrying out the invention and the drawings to be described later are appended in parentheses for reference, but the constituent elements of the present invention are not limited to the appended description.

The respiratory function test apparatus (spirometer 100) of the present invention 1
Measuring means (flow sensor 50, differential pressure tube 30, pressure sensor 11, A / D converter 12, CPU 14) for measuring a respiratory flow rate and a respiratory volume;
Based on the respiratory flow rate and the respiratory volume measured in a predetermined period (1 second or 2 second analysis period) in the expiration decay region (3 to 7 seconds from the detection of the call) after the start of the forced call, Relational expression determining means for determining a relational expression with the respiratory capacity (CPU 14 that executes the process of S117);
Forced vital capacity estimating means for estimating the forced vital capacity based on the relational expression determined by the relational expression determining means (CPU 14 executing the processing of S118);
It is characterized by providing.
According to this, since the subject's forced vital capacity can be estimated at a timing before the end of expiration, the burden on the subject can be reduced.

The respiratory function test apparatus (spirometer 100) of the present invention 2
A respiratory function testing device according to the present invention 1,
The predetermined period is set within a predetermined time after the effort call is started.
According to this, since the subject's forced vital capacity can be estimated in a short period from the start of the effort call, the burden on the subject can be reduced.

The respiratory function test apparatus (spirometer 100) of the present invention 3
The respiratory function testing device of the present invention 1 or 2,
Further comprising notifying means (CPU 14 for notifying S114 and S120) for informing the subject to exhale during the period from the start of the effort call until the end of expiration is confirmed,
The notification means has an evaluation value ([1 second amount / hour vital capacity] × 100) acquired at a timing before the end of expiration is confirmed after the elapse of the predetermined period as a predetermined reference value (70% ), The notification is continued (determined No in S116 and the notification of S120 is executed), and when the evaluation value has not reached the reference value, the timing before the end of expiration is confirmed. The notification is ended (Yes in S116, the measurement is ended without executing the notification in S120).
According to this, for subjects who may have a pulmonary function disease, the burden is reduced without continuing exhalation, while for healthy subjects, the exhalation is continued and actual measured values of forced vital capacity are obtained. can do.

The respiratory function test apparatus of the present invention 4
A respiratory function testing device of the present invention 3,
The evaluation value is a value based on time vital capacity ([1 second amount / hour vital capacity] × 100).
According to this, it is possible to determine whether or not expiration can be continued using the measured time vital capacity.

The respiratory function test apparatus of the present invention 5
The respiratory function testing device of the present invention 4,
The evaluation value is a ratio of the amount of 1 second to the time vital capacity.
According to this, it is possible to determine whether or not to continue exhalation using an evaluation value that approaches the vital capacity with time.

The respiratory function test apparatus of the present invention 6
The respiratory function testing device of the present invention 5,
The time vital capacity corresponding to the elapsed time from the start of the effort call is acquired every predetermined time (the time vital capacity is acquired every one second in S120A of FIG. 7), and the ratio of the one second amount to the acquired time vital capacity Is used as an evaluation value, and the notification is continued during a period in which the evaluation value reaches the reference value (indication of continuation of exhalation during a period determined to be No in S120A).
According to this, the timing of the end of measurement can be varied step by step according to the subject's symptoms.

The respiratory function test apparatus of the present invention 7
The respiratory function testing device of the present invention 4,
The evaluation value is a time vital capacity.
According to this, it is possible to determine whether or not to continue exhalation using a time vital capacity such as a one second quantity that is normally measured in the measurement of forced vital capacity.

  ADVANTAGE OF THE INVENTION According to this invention, the test subject's burden at the time of forced vital capacity measurement can be reduced.

FIG. 1 is a functional block diagram showing an example of a spirometer. FIG. 2 is a diagram illustrating an example of a flow sensor included in the spirometer. FIG. 3 is a diagram showing an example of the forced vital capacity measurement process executed by the CPU of the spirometer. FIG. 4 is a diagram showing an example of a flow volume curve measured by a spirometer. FIG. 5 is a diagram showing a method for determining a linear function and an estimation example of forced vital capacity. FIG. 6 is a diagram showing the relationship between the actual value and the estimated value of the forced vital capacity. FIG. 7 is a diagram showing another example of the forced vital capacity measurement process executed by the CPU of the spirometer.

  Hereinafter, a spirometer 100 which is an example of a respiratory function testing device according to the present invention will be described with reference to the drawings. In the drawings, the forced vital capacity may be indicated as “FVC”.

[Configuration of Spirometer 100]
As shown in FIG. 1, the spirometer 100 includes a main body 10 and a flow sensor 50. The main body 10 includes an operation key 17, a display 18, a speaker 20, a printer 21, a pressure sensor 11, an A / D converter 12, a CPU 14, a ROM 13, a RAM 15, and an RS232C connector 16. The main body 10 and the flow sensor 50 are connected by a differential pressure tube 30.

  The flow sensor 50 is detachably mounted on the main body unit 10 and generates a differential pressure proportional to the respiratory flow rate. As shown in FIG. 2, the flow sensor 50 includes a connection port 52 for connecting a filter and a mouthpiece (not shown). When the subject breathes through the mouthpiece connected to the connection port 52, a differential pressure is generated in the flow sensor 50, and this differential pressure is transmitted through the differential pressure tube 30 composed of two tubes. Is transmitted to the pressure sensor 11 in the main body 10.

  The operation keys 17 are used when selecting measurement items or inputting subject information (age, height, etc.). For example, it consists of ten numeric keys from 0 to 9, direction keys for selecting measurement items, and the like. Also included is a print key operated when printing out the data output to the display 18. The flow sensor 50 is provided outside the main body as shown in FIGS. 1 and 2, one end of a differential pressure tube 30 composed of two tubes is connected, and the other end is a differential pressure tube connection port of the main body 30. (Not shown). In the state where the subject holds the flow sensor 50, the mouthpiece connected to the connection port 52 is included in the mouth, and the respiratory flow is measured by breathing, and the measured respiratory flow is integrated. Thus, respiratory capacity such as forced vital capacity is measured.

  The pressure sensor 11 outputs an analog signal proportional to the detected differential pressure. In this example, it is a semiconductor differential pressure sensor, for detecting a differential pressure between tube connection ports, and for outputting a voltage proportional to the differential pressure detected by the differential pressure detection unit. An output terminal is provided. The A / D converter 12 is for converting an analog electronic signal into a digital signal. In this example, it is a semiconductor A / D converter, which converts an analog signal output from the output terminal of the pressure sensor 11 into a digital signal that can be processed by the CPU 14 to be described later, and outputs the digital signal from the digital output terminal.

  The CPU 14 executes a measurement program such as forced vital capacity stored in the ROM 13 by using the RAM 15 as a work area, thereby controlling the operation of each connected component or receiving a signal from each component. Various processes are performed. In this example, processing for calculating a respiratory flow rate such as an expiratory flow rate or an inspiratory flow rate is performed based on a digital signal that is an output from the A / D converter 12 and indicates a value proportional to the differential pressure. This calculation is performed based on a relational expression between a differential pressure and a respiratory flow rate that are stored in advance. That is, the differential pressure is specified from the digital signal, and the specified differential pressure is input to the relational expression to calculate the respiratory flow rate. In this example, the respiratory capacity such as the forced vital capacity is calculated by integrating the respiratory flow rate. The data measured here is accumulated in the RAM 15, and when the measurement is completed, the data accumulated in the RAM 15 is stored in the ROM 13.

  The ROM 13, which is a non-volatile memory, stores measurement data as described above, and also stores a measurement program for respiratory functions such as forced vital capacity. The ROM 13 also stores guide audio data, and this audio data is reproduced by the speaker 20. The display 18 is an LCD display, and is provided on the upper surface of the main body unit 10 and outputs predetermined data to the screen by performing output control from the CPU 14 via an LCD driver circuit (not shown). The printer 21 is, for example, a thermal printer, and outputs predetermined data on paper so that the CPU 14 can perform printing control via a thermal head driver, and is displayed on the display 18, for example. Print data. The speaker 20 is an audio output means for prompting the subject to exhale or inhale by an audio guide, and an audio based on audio data stored in the ROM 13 in advance is output.

  The RS232C connector 16 is a terminal for transmitting / receiving data to / from a device outside the spirometer such as a PC via a RS232C cable. In this example, the interface with the external PC is an RS232C connector, but the present invention is not limited to this and may be another interface.

  The flow sensor 50 will be described in detail with reference to FIG. A connection port 52 for connecting a filter and a mouthpiece is provided on a side surface of the flow sensor case 51 serving as a housing of the flow sensor 50. A handle 56 for holding the flow sensor case 51 is provided below the flow sensor case 51.

  In the flow tube 53 in the flow sensor case 51, a screen 55 is disposed as a resistor that generates respiratory resistance. The screen 55 is a mesh-like material and is arranged so as to block the gas flow. When a gas flow occurs in the flow pipe 53, a differential pressure is generated before and after the screen 55. The pressure before and after the screen 55 is supplied to a differential pressure tube connection port (not shown) of the main body via a pressure port disposed before and after the screen 55 and a differential pressure tube 30 connected to each of the pressure ports. ). That is, one of the two tubes constituting the differential pressure tube 30 transmits the pressure at the front of the screen (on the connection port 52 side) to one tube connection port connected to the tube, and the other transmits the pressure at the rear of the screen. It transmits to the other tube connection port connected with a tube. On the main body 50 side, the flow rate of the gas flowing in the flow tube 53, that is, the respiratory flow rate can be measured by detecting the differential pressure between the two tube connection ports. This respiratory flow rate is also called a respiratory flow rate. Note that this type of flow sensor is a so-called differential pressure type and is widely used.

[Measurement of forced vital capacity]
Next, the forced vital capacity measurement process executed by the spirometer 100 (CPU 14 or the like) will be described with reference to FIG. First, on the initial screen, icons corresponding to various measurements such as “forced vital capacity measurement” are displayed on the display 18. When “forced vital capacity measurement” is selected by the operation key 17, the forced vital capacity measurement program is activated, and the respiratory flow and the respiratory capacity based on the respiratory flow can be measured.

  In this state, when the subject grips the flow sensor 5, includes the mouthpiece provided in the flow sensor 5 in his mouth, and breathes in accordance with the instructions of the doctor or laboratory technician, the above-described measurement means (flow sensor 50 The differential flow tube 30, the pressure sensor 11, the A / D converter 12, the CPU 14, etc.) measure the respiratory flow rate (flow), and further measure the respiratory volume (volume) as an integral value of the respiratory flow rate. The time-series data of the respiratory flow and respiratory volume measured here is accumulated in the RAM 15, and the horizontal axis (X-axis) is the respiratory volume and the vertical axis (Y-axis) is the respiratory flow as shown in FIG. The flow volume curve thus obtained is displayed on the display 18. The flow volume curve is a curve showing the relationship between the respiratory volume and the respiratory flow rate at the same time point. In the example of FIG. 4, the flow volume curve of a normal healthy person with% vital capacity> 80%, 1 second rate> 70% and the flow volume curve of a subject with obstructive disease with 1 second rate <30% are shown. It is shown.

  Processing executed by the forced vital capacity measurement program according to the present embodiment will be described with reference to FIG. In this measurement, first, the maximum inspiratory position is measured, and the maximum expiratory position is measured after “a single call” that exhales at a stretch from the maximum inspiratory position. At this time, the amount of breath called for the first second is measured as “one second”. Then, the difference between the maximum inspiratory position at this time and the final maximum expiratory position is measured as the forced vital capacity. However, when it is determined that the subject may have an obstructive disease during the measurement, the estimated value of the forced vital capacity is calculated and the measurement is terminated without continuing the expiration to the maximum expiratory position.

  When the forced vital capacity measurement program is executed, it is first determined whether or not resting ventilation has been confirmed (S100). For example, when the period when the differential value of respiratory flow is switched from positive to negative (or from negative to positive) falls within a certain range (for example, a range of 5 seconds to 10 seconds) for a predetermined number of times, the resting ventilation is confirmed. Shall be. Until resting ventilation is confirmed (No in S100), the speaker 20 outputs a voice “please breathe normally and comfortably” to instruct resting ventilation (S101).

  When resting ventilation is confirmed (Yes in S100), the speaker 20 is instructed to inhale the maximum inspiration by outputting a voice saying “I will suck my chest” (S110). Subsequently, by outputting a voice “suck” from the speaker 20 (S111), the inspiration is continued to prompt the subject to breathe to the full lung.

  In this notification process, after the notification in S111, after waiting for a predetermined time (for example, 1 second), it is determined whether or not the intake air flow velocity is equal to or lower than a preset threshold value (for example, 1 ml / s) (S112). If it is determined in S112 that it is not less than or equal to the threshold (No), the notification in S111 and the determination in S112 are performed again. When it is determined in S112 that the threshold value is not more than the threshold value (Yes), that is, when the end of inspiration is detected, a voice “scream out” is output from the speaker 20 (S113), and the subject is immediately , And continuously output a voice saying “Exhale” (S114) to urge the subject to exhale the breath remaining in the lungs by continuing the exhalation.

  After the notification in S114, after waiting for a predetermined time (for example, 1 second), it is determined whether or not a predetermined analysis period (for example, 4 seconds) has elapsed since the call was detected (S115). The detection time of the call is, for example, the time when the differential value (expiration acceleration) of the expiratory flow velocity reaches the maximum value. When it is determined in S115 that the analysis period has not elapsed (No), the process waits again for a predetermined time, and performs notification in S114 and determination in S115. If it is determined in S115 that the analysis period has passed (Yes), an evaluation value that is a ratio of the amount of 1 second to the time vital capacity (for example, 4 seconds amount) acquired at the present time, [ 1 second amount / hour vital capacity (4 second amount)] × 100, and further, it is determined whether or not the evaluation value is less than a reference value (for example, 70%) (S116).

  Here, when the 1-second rate, which is the ratio of the 1-second amount to the forced vital capacity, is less than 70%, it can be determined that the subject has a possibility of an obstructive disease. Naturally, if the above-described evaluation value does not reach 70% before the end of expiration is confirmed, it is finally determined that the 1-second rate of the subject is less than 70%. That is, when the evaluation value is less than 70% in S116, the subject has a possibility of occlusive disease. In addition, the said evaluation value becomes less than 70% in the ratio of 60% or more of the subjects whose 1 second rate is less than 60%, and the said value in 99% or more of the subjects whose 1 second rate is less than 50%. There is a statistical result that the evaluation value is less than 70%, and the evaluation value is less than 70% at a rate of 100% of subjects whose 1 second rate is less than 40%.

  If it is determined in S116 that the evaluation value is less than the reference value (Yes), the relational expression between the respiratory volume (volume) and the expiratory flow velocity (flow) in the analysis period from 3 seconds to 4 seconds from the detection of the call Is determined (S117).

  For example, a linear function expression of the respiratory volume (X axis) and the expiratory flow rate (Y axis) in the target period is determined based on the least square method. In this embodiment, it is assumed that the number of samples (n) in the analysis period is 40 points (that is, a sampling period of 25 msec), and the measurement result of Expression (1) is obtained. If the linear function expression to be obtained at this time is Expression (2), constants (slope and intercept) of the linear function expression are determined by Expressions (3-1) and (3-2).

  An example of the linear function equation thus obtained is shown in the flow volume curve. FIG. 5 shows a flow volume curve of a subject having an obstructive disease with a 1 second rate of less than 30%. The linear function equation determined using 40 points of (respiration volume, expiratory flow rate) coordinates in the analysis period shown in the figure (1 second from the detection of the call to 3 to 4 seconds) is shown as a straight line. ing. Next, based on the linear function equation thus obtained, the respiratory volume (Y) when the expiratory flow velocity (X) is 0 is calculated (S118). The value calculated in this way is used as an estimated vital capacity value. The value of the respiratory capacity (Y) at the intersection of the X axis and the approximate line in FIG. 5 is the estimated vital capacity value, which is about 3.5 L in this example.

  Furthermore, the estimated vital capacity value calculated in S118 is displayed on the display 18 (S119). Then, the speaker 20 is notified of the end of the measurement by outputting a sound “the measurement is finished” from the speaker 20.

  On the other hand, if it is determined in S116 that the evaluation value is not less than the reference value (evaluation value ≧ 70%) (No), a voice “vomit” is output from the speaker 20 (S120), and expiration is continued. Urge the subject to exhale the remaining breath in the lungs. After the notification in S120, after waiting for a predetermined time (for example, 1 second), it is determined whether or not the expiratory flow rate is equal to or lower than a preset threshold (for example, 1 ml / s) (S121). If it is determined in S121 that it is not less than the threshold value (No), the notification in S120 and the determination in S121 are performed again. If it is determined in S121 that the threshold value is not more than the threshold value (Yes), that is, if the end of expiration is detected, the differential capacity between the maximum inspiratory position and the maximum expiratory position is measured as the forced vital capacity and displayed on the display 18 ( S122). Then, the speaker 20 is notified of the end of the measurement by outputting a sound “the measurement is finished” from the speaker 20.

  As described above, if the evaluation value is equal to or higher than the reference value (No in S116), that is, if there is a high possibility that the subject is a healthy person, the patient is prompted to continue exhalation until the end of expiration is detected. The measured value is acquired by ending the measurement after the end is confirmed. On the other hand, if the evaluation value is less than the reference value (Yes in S116), that is, if there is a possibility that the subject is not a healthy person, the calculated estimated vital capacity without waiting for the end of expiration. To finish the measurement. If the subject's lung function is reduced due to factors such as obstructive disease, the test subject will be burdened by continuing exhalation until the end of exhalation. In this embodiment, evaluation is performed by the method described above. If there is a risk of having an obstructive disease, etc., based on the evaluation value, present the calculated estimated vital capacity as the result of forced vital capacity without continuing expiration until the end of expiration. Therefore, the burden on the subject is reduced. In this example, since the evaluation value is always less than 70% in S116 for a severe patient with a 1 second rate of less than 40%, the exhalation is not continued until the end of expiration for such a severe patient. The pain at the time of forced vital capacity measurement can be surely relieved.

FIG. 6 shows the relationship between the actual value (X axis) of the forced vital capacity and the estimated value of the vital capacity (Y axis). In this example, 669 samples with a 1 second rate of less than 40% were extracted from 30240 samples of the flow volume curve, and 26 of them were extracted at random. About these extracted flow volume curves, 1 second or 2 seconds was set as the analysis period in the period of 3 to 7 seconds from the call detection, and the sample data (respiration volume, expiratory flow rate) in the analysis period was used as described above. A linear function was determined by the method, and an estimated vital capacity value was calculated based on the determined linear function. FIG. 6 shows the relationship between the actual measured vital capacity (X axis) based on these flow volume curves and the estimated vital capacity (Y axis) estimated from the analysis period of each flow volume curve. As shown, it has a very high correlation (Y = 1.0086X−0.0203, R ² = 0.9957), and it was confirmed that they were almost matched. All the estimated values were within the range of the actual measurement value ± 3%.

  From the result shown in FIG. 6, it is confirmed that the estimated value obtained by the method for estimating the forced vital capacity shown in the present embodiment is a reliable value. Therefore, if there is a possibility of having an obstructive disease based on the evaluation value based on the time vital capacity (4 seconds in the above example), the estimated vital capacity is presented as the measurement result without continuing the expiration until the end of expiration. Even if it does not interfere, it becomes possible to finish the measurement of the forced vital capacity without imposing a burden on the subject within a short time after the call detection.

(Other embodiments)
Finally, an embodiment different from the above-described embodiment will be illustrated.

  In the above embodiment, an example in which an analysis period of 1 second or 2 seconds is provided within a period of 3 to 7 seconds from the start of the call has been described. However, the start is started within a period of 3 to 7 seconds from the start of the call. An arbitrary analysis period can be set as the time point and the end time point. Moreover, the analysis period does not necessarily have to be provided within a period of 3 to 7 seconds from the start of the call, and the statistical result of the estimated vital capacity is within a range close to the actual measurement value (for example, within ± 5%). It only has to be provided.

  In the above-described embodiment, an example in which an analysis period based on the elapsed time from the start of a call has been described. However, an analysis period based on a respiratory volume (volume) may be provided, and an expiratory flow rate (flow) may be provided. An analysis period based on the above may be provided. For example, a period in which the respiratory volume is 2.0 L to 2.5 L may be set as the analysis period, a period in which the expiratory flow rate is 0.4 L / s to 0.2 L / s may be set as the analysis period, and the forced vital capacity is obtained as a statistical result. A period in which the estimated value is in a range close to the actually measured value (for example, within ± 5%) is preferable.

  In the above-described embodiment, the example in which the ratio of the 1-second amount to the 4-second amount is set as the evaluation value at the time of S116 after 4 seconds from the start of the call is described. The ratio of 1 second amount may be used as the evaluation value. For example, the ratio of 1 second amount to 3 second amount may be used as the evaluation value. If 5 seconds have elapsed at the time of S116, the ratio of the 1-second amount to the 5-second amount may be used as the evaluation value. Moreover, in the said embodiment, when the evaluation value was less than 70%, the example which calculates an effort vital capacity estimated value was demonstrated, For example, an evaluation value is less than 60%, ie, a test subject is more severe. If there is a possibility, an estimated effort vital capacity value may be calculated, and a value suitable as a reference value to be compared with the evaluation value may be set.

  In the above embodiment, when the analysis period has elapsed from the call, if the evaluation value is less than the reference value, the estimated vital capacity is calculated, and if the evaluation value is greater than or equal to the reference value, the forced vital capacity is measured. As shown in FIG. 7, the evaluation value is calculated at a plurality of timings after the call and is compared with the reference value, and the estimated vital capacity is calculated each time, or the It may be determined whether to continue the actual measurement. In the example of FIG. 7, after S120, after waiting for a predetermined time (for example, 1 second), an evaluation value that is a ratio of the amount of 1 second to the time vital capacity (for example, the amount of 5 seconds) currently acquired is represented by [ 1 second amount / hour vital capacity (5 second amount)] × 100, and it is determined whether or not the evaluation value is less than a reference value (for example, 70%) (S120A). If it is less than the reference value (YES in S120A), a linear function equation is determined using the coordinates of the sample (respiration volume, expiratory flow rate) in the latest predetermined period (for example, the latest 1 second) (S117A). Further, the forced vital capacity estimated value is calculated based on the one-hour formula determined in S117 (S118), the calculated value is displayed (S119), and the measurement is terminated. On the other hand, if the evaluation value is equal to or greater than the reference value in the determination in S120A (NO in S120A), the actual measurement of the vital capacity is continued (S121 to S121).

  That is, in the example shown in FIG. 7, if the elapsed time from the start of the call is X seconds, the evaluation value is calculated by (1 second amount / X second amount) × 100, and the evaluation value is less than the reference value The forced vital capacity estimated value is calculated, and when the evaluation value is equal to or greater than the reference value, the process of continuing exhalation (calculating the evaluation value based on the next (X + 1) second amount) is repeatedly executed. When end expiratory gas is detected, the forced vital capacity is finally measured, and when the evaluation value becomes less than the reference value before the end of exhalation is detected, The forced vital capacity estimated value is calculated without waiting, and the measurement ends. As a result, the time vital capacity acquired as time elapses increases to 4 seconds, 5 seconds,..., And the evaluation value that is the ratio of 1 second to the time vital capacity gradually increases to the 1 second rate. Will approach. Then, when the evaluation value falls below the reference value, the measurement is finished and the estimated vital capacity is displayed, and if the evaluation value does not fall below the reference value until the end of expiration, the actual value of the forced vital capacity is obtained. Become. By setting it as such embodiment, the timing of completion | finish of measurement can be varied in steps according to a test subject's symptom. For example, in critically ill patients, the estimated amount of forced vital capacity is calculated at an early stage and the measurement ends.If the symptoms are relatively mild, the estimated value of forced vital capacity is calculated after a longer call. Is calculated and measurement ends.

  In the above-described embodiment, the example of using the ratio of the 1-second amount to the time vital capacity for which measurement has been completed at the time of determination has been described. However, the present invention is not limited thereto, and the temporal vital capacity itself including the one-second amount as an evaluation value May be used. That is, in S116 of FIG. 3, it is determined whether or not to urge continuation of expiration until the end of expiration is confirmed, depending on whether or not the measured vital capacity such as the amount of one second is less than a predetermined value. May be. According to this, it is possible to determine whether or not to continue exhalation using a time vital capacity such as a one second quantity that is normally measured in the measurement of forced vital capacity. Further, the present invention is not limited to this, and it may be determined whether or not to urge continuation of exhalation based on other measurement values related to the respiratory function acquired before the end of exhalation.

  In the above embodiment, the example of estimating the forced vital capacity based on the linear function formula determined by the least square method has been described. However, the present invention is not limited to this, and based on the quadratic function formula determined by the least square method. The effort vital capacity may be estimated. Further, the forced vital capacity may be estimated based on an approximate expression obtained by a method other than the method of least squares.

  In the above embodiment, an example was described in which the difference in capacity between the maximum inspiratory position and the maximum expiratory position when forced calling from the maximum inspiratory position to reach the maximum expiratory position is the forced vital capacity. The operation of measuring the difference in capacity between the maximum inspiratory position and the maximum expiratory position when reaching the maximum expiratory position by making an effort call was performed three times, and the amount of 1 second was also measured in each measurement. Of the measured values, the amount of 1 second + (the difference in capacity between the maximum inspiratory position and the maximum expiratory position) is the maximum (difference in capacity between the maximum inspiratory position and the maximum expiratory position) as the forced vital capacity. You may do it. Correspondingly, the operation of acquiring the estimated vital capacity value as a measured value is executed three times, and a one-second amount is measured in each measurement, and among the obtained measured values, one second amount + effort The estimated effort vital capacity when the estimated vital capacity is maximized may be used as the measurement result.

  In the above-described embodiment, an example in which continuation of exhalation is instructed by a voice guide has been described. Note that the period until the end of expiration is detected is the normal display mode, and when the end of expiration is detected, a special display mode that is different from the normal display mode is used. Become.

13 ... ROM
14 ... CPU
18 ... Display 50 ... Flow sensor 100 ... Spirometer

Claims (5)

A measuring means for measuring respiratory flow rate and volume,
A relational expression determining means for determining a relational expression between the respiratory flow rate and the respiratory capacity in the predetermined period based on the respiratory flow rate and the respiratory volume measured in the predetermined period in the exhaled breathing area after the effort call starts;
Forced vital capacity estimating means for estimating the forced vital capacity based on the relational expression determined by the relational expression determining means;
A respiratory function testing device comprising: The respiratory function testing device according to claim 1,
The respiratory function testing apparatus according to claim 1, wherein the predetermined period is set within a predetermined time after the start of the effort call. A respiratory function testing apparatus according to claim 1 or 2,
A notification means for notifying the subject of exhalation in a period from the start of the effort call until the end of expiration is confirmed;
The notification means uses the ratio of the amount of 1 second with respect to the time vital capacity acquired at a timing before the end of expiration is confirmed after the elapse of the predetermined period as an evaluation value, and the evaluation value is a predetermined value. Respiratory function test characterized in that the notification is continued when the reference value is reached, and the notification is terminated at a timing before the end of expiration is confirmed when the evaluation value does not reach the reference value. apparatus. A respiratory function testing device according to claim 3 ,
A period during which the vital capacity corresponding to the elapsed time from the start of the effort call is acquired every predetermined time, and the evaluation value reaches the reference value with the ratio of the amount of 1 second to the acquired vital capacity as an evaluation value Continues the above-mentioned notification. The respiratory function testing device according to claim 1 or 2 ,
A notification means for notifying the subject of exhalation in a period from the start of the effort call until the end of expiration is confirmed;
The notification means uses the time vital capacity acquired at a timing before the end of expiration is confirmed after the elapse of the predetermined period as an evaluation value, and when the evaluation value reaches a predetermined reference value, the notification And the notification is ended at a timing before the end of expiration is confirmed when the evaluation value does not reach the reference value .