TW202239374A - Assessment method and detection device for blood sugar concentration including an expiratory capture measurement step and a blood sugar assessment step - Google Patents

Abstract

A blood sugar concentration assessment method allows a user to perform measurement in a non-invasive manner and includes an expiration capture measurement step and a blood sugar assessment step. The expiration capture measurement step is to capture an end-expiratory volume of an expiratory gas exhaled by the user within a continuous time interval, and to measure a carbon dioxide concentration of the end-expiratory flow, so as to estimate the blood sugar concentration of the user, wherein the end-expiratory volume is not more than 10% of a total expiratory volume of the expiratory gas. Next, in the blood sugar assessment step, the blood sugar assessment is carried out based on the carbon dioxide concentration in the end-expiratory captured from the expiratory gas, which can eliminate the interference of a dead space gas in the expiratory gas and improve the accuracy of the assessment. In addition, the present invention further provides a detection device for performing the aforementioned assessment method.

Description

Evaluation method and detection device for blood glucose concentration

The present invention relates to an evaluation method and detection device for blood sugar concentration, in particular to a non-invasive blood sugar concentration evaluation method and detection device.

When breathing, the breathed gas will be exchanged with the blood in the alveoli, so the gas exhaled by a person will have a certain degree of correlation with the components in his own blood. At present, in laboratory medicine, specific gas analysis is often performed on the exhaled gas of the subject to test whether the subject suffers from related diseases such as lung disease, asthma or liver problems, and to evaluate the subject. The health status of the test subjects will facilitate follow-up disease treatment and management. Wherein, since the carbon dioxide (CO ₂ ) concentration in the expiratory gas is positively correlated with the blood sugar concentration, by measuring the carbon dioxide concentration in the exhaled gas of the subject, the blood sugar concentration of the subject can be further inferred, and thus Determine whether the subject has blood sugar metabolism, diabetes and other related diseases. Japanese Invention Patent No. JP6352188B2 Approval Announcement No. discloses a method for measuring glucose metabolism ability, by letting the tester take glucose labeled with isotope C, and measuring the carbon dioxide concentration in the tester's exhaled breath at different time points, And observe the content of carbon dioxide labeled with isotope C in the overall carbon dioxide gas, so as to evaluate the tester's ability to metabolize sugar.

Based on the convenience of the non-invasive detection method and detection process, the method of measuring the breath gas to evaluate the blood sugar has been widely studied in related fields. In addition to gas, it also includes gas from the mouth, respiratory tract and bronchi. This type of gas is called dead space gas in medicine, and does not participate in the exchange between breathing gas and blood in the alveoli, so this is invalid The presence of gas in the cavity will cause errors in the detection method of judging the blood sugar concentration through the carbon dioxide concentration, and cause insufficient accuracy in evaluating the blood sugar concentration of the patient or diseases such as diabetes.

Therefore, the purpose of the present invention is to provide a blood sugar concentration assessment method to improve the accuracy of blood glucose concentration assessment.

Therefore, the method for assessing blood sugar concentration of the present invention is for a user to assess blood sugar status in a non-invasive manner, which includes a breath capture measurement step and a blood sugar assessment step.

The exhalation capture measurement step is to capture the terminal expiratory volume of an expiratory gas exhaled by the user in a continuous time interval T ₀ ~T _n , and measure the carbon dioxide concentration of the terminal expiratory volume, Wherein, T ₀ is an exhalation start time, T _n is an exhalation end time, and the final expiratory volume is extracted from the time between an initial acquisition time T _X1 and an end acquisition time T _X2 interval, and T ₀ < T _X1 , T _X1 < T _X2 ≦ T _n , X1, X2, n are natural numbers, and the expiratory volume at the end is not greater than the total expiratory volume of the continuous time interval T ₀ ~ T _n 10% of.

The blood glucose assessment step is to calculate and estimate the user's blood glucose concentration by using the carbon dioxide concentration of the end expiratory volume, so as to obtain a blood glucose assessment result.

Another object of the present invention is to provide a detection device suitable for measuring carbon dioxide concentration in a non-invasive manner to obtain blood glucose assessment results.

Therefore, the detection device of the present invention is used for a user to detect blood glucose concentration in a non-invasive manner, and includes a gas interception unit, a conversion unit, a sensing unit, and an analysis unit.

The gas entrapment unit includes a hollow tube body having an inlet for receiving exhalation gas exhaled by the user, and an exhaust port for discharging the exhalation gas away from the inlet. breath.

The conversion unit includes an audio frequency converter, which is arranged in the hollow tube and communicated with the air inlet, and the expiratory gas introduced from the air inlet can enter the audio frequency converter at the same time, and the audio frequency converter The expiratory gas entering at different times can be converted into different sound wave signals according to the gas volume.

The sensing unit is disposed in the hollow tube and includes at least one gas sensor for sensing the carbon dioxide concentration in the exhalation gas.

The analysis unit is respectively connected to the sensing unit and the conversion unit for signals, and a time-dependent gas volume signal of the expiratory gas is calculated by using the acoustic wave signals obtained at different times, and can be obtained by using the time-dependent gas volume signal results The sensing unit measures the carbon dioxide concentration obtained in a specific time period.

The effect of the present invention lies in that: the terminal expiratory volume is extracted from the expiratory gas through the exhalation extraction step, so as to eliminate the interference from the no-space gas in the oral cavity, respiratory tract or bronchi, etc., and can only be based on the measured The carbon dioxide concentration obtained at the end of the exhalation is used to evaluate the blood sugar, thereby improving the accuracy of the evaluation.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same numerals.

Referring to FIG. 1 , the method for assessing blood sugar concentration of the present invention can use a non-invasive detection device 200 for users to non-invasively assess blood sugar concentration.

The detection device 200 includes a gas interception unit 2 , a conversion unit 3 , a sensing unit 4 , and an analysis unit 5 .

The gas trapping unit 2 includes a hollow tube body 21 and an exhaust member 22. The hollow tube body 21 has an air inlet 211 for receiving the exhalation gas exhaled by the user, and an air inlet 211 away from the air inlet. Port 211 is an exhaust port 212 for exhaling the exhalation gas. The exhaust member 22 communicates with the exhaust port 212 and is used for forcing the expiratory gas entering the hollow tube body 21 to the outside. The flow rate of the exhaust gas is controlled by the exhaust member 22, so that the hollow tube body 21 maintains a state of gas circulation during the detection process, so that the exhalation gas is discharged from the exhaust port 212 according to time during the exhalation process. To avoid gas accumulation, it can be used to control only the expiratory gas for a specific time interval to be kept in the hollow tube 21 . In this embodiment, the exhaust element 22 is an example of a fan disposed at the exhaust port 212 , but it is not limited thereto.

The conversion unit 3 includes an audio frequency converter 31 and a receiver 32. The audio frequency converter 31 is arranged in the hollow tube body 21 and communicates with the air inlet 211. The exhaled air introduced from the air inlet 211 The gas can enter the audio frequency converter 31 at the same time, and the audio frequency converter 31 can convert the expiratory gas into different sound wave signals according to the volume of gas blown in at different times; the receiver 32 is arranged adjacent to the audio frequency converter 31 , for receiving the sound wave signals, and can be used for receiving and amplifying the sound wave signals. The audio converter 31 can be selected from a whistle sound generator. In this embodiment, it is taken that the audio converter 31 is a whistle generator and the receiver 32 is a microphone as an example, but it is not limited thereto.

The sensing unit 4 is disposed in the hollow tube 21 and includes at least one gas sensor 41 for sensing the concentration of carbon dioxide in the exhalation gas. In this embodiment, the sensing unit 4 has a gas sensor 41 for measuring the concentration of carbon dioxide, and the gas sensor 41 is disposed in the hollow tube adjacent to the exhaust port 212 As an example, however, in actual implementation, the number and installation positions of the gas sensors 41 are not limited to the above-mentioned implementation.

In some embodiments, the sensing unit 4 may have two gas sensors 41 for measuring the carbon dioxide concentration and the oxygen concentration in the exhaled gas, respectively, so as to simultaneously measure the carbon dioxide concentration in the exhaled gas, and oxygen concentration.

The analysis unit 5 is connected to the sensing unit 4 and the conversion unit 3 respectively, and can receive the carbon dioxide concentration sensing results of the sensing unit 4 at different times to obtain a time-dependent concentration signal; The conversion unit 3 calculates a time-dependent gas volume signal of the expiratory gas from the sound wave signals obtained at different times, and can use the time-dependent gas volume signal to calculate the total expiratory volume and the final expiratory volume , and a terminal expiratory time interval corresponding to the terminal expiratory volume, so as to further obtain the carbon dioxide concentration measured by the sensing unit 4 corresponding to the terminal expiratory time interval. In detail, the analysis unit 5 obtains the total expiratory volume of the expiratory gas through the integral calculation of the time-dependent gas volume signal and time, and then calculates the final expiratory volume through the total expiratory volume, and obtains correspondingly The measurement time interval of the terminal expiratory volume, and then by comparing the time-dependent concentration signal of the carbon dioxide, the carbon dioxide concentration of the exhaled gas within the measurement time interval of the terminal expiratory volume can be obtained.

Referring to Fig. 1 and Fig. 2, a first embodiment of the method for assessing blood sugar concentration of the present invention is for the user to use the aforementioned detection device 200 to detect the carbon dioxide concentration of exhaled gas, and to evaluate his own blood sugar concentration correspondingly . The first embodiment includes a breath capture measurement step 61 and a blood glucose assessment step 62 .

The exhalation capture measurement step 61 is to capture the terminal expiratory volume of the expiratory gas exhaled by the user in a continuous time interval T ₀ ~T _n , and measure the carbon dioxide to obtain the terminal expiratory volume concentration. Among them, T ₀ is an exhalation start time, T _n is an exhalation end time, n is a natural number, and the final expiratory volume is extracted from a final exhalation time interval, and the final exhalation time interval It is between a start capture time T _X1 and an end capture time T _X2 , T ₀ < T _X1 , T _X1 < T _X2 ≦ T _n , X1, X2, and n are natural numbers, and the final expiratory volume Not greater than 10% of the total expiratory volume in the continuous time interval T ₀ ~T _n . That is to say, the terminal expiratory volume is the expiratory volume obtained from a time interval before the expiration end time (ie, the terminal expiratory time interval).

The blood glucose assessment step 62 is to calculate and estimate the blood glucose concentration of the user by using the carbon dioxide concentration of the end expiratory volume.

In more detail, the exhalation capture measurement step 61 is to make the user exhale from the air inlet 211 of the hollow tube body 21, let the exhaled gas pass through the air inlet 211, the audio frequency converter The device 31 is introduced into the hollow body 21. The sensing unit 5 continuously senses the concentration of carbon dioxide in the exhalation gas entering the hollow tube 21 to obtain the time-dependent concentration change result of carbon dioxide corresponding to the continuous time interval T ₀ ~T _n . At the same time, the expiratory gas entering the hollow tube body 21 can generate sound wave signals with different intensities and frequencies through the audio frequency converter 31, and because the sound wave signals of different frequencies and intensities will correspond to different gas volumes, it can By converting the acoustic wave signals into the time-dependent gas volume signal through the analysis unit 5, and using the time-dependent gas volume signal and time integral calculation, the expiratory gas corresponding to the continuous time interval T ₀ ~ T _n can be obtained The total expiratory volume and/or the gas volume in a specific time period (equivalent to the time-dependent gas volume of the expiratory gas), then, the final expiratory volume can be calculated by using the total expiratory volume, and Based on this, the start capture time T _X1 and the end capture time T _X2 of the last exhalation time interval are defined. Afterwards, the carbon dioxide concentration of the user's exhaled gas in the last exhalation time interval can be obtained by using the result of the time-dependent concentration change of carbon dioxide.

Finally, the carbon dioxide concentration (average value) in the end-expiratory time interval can be compared with a standard blood sugar level to obtain a blood sugar assessment result. For example, if the total expiratory volume calculated after the user exhales is 2L, then the user's final expiratory volume is not greater than 200ml (not greater than 10% of the total expiratory volume), therefore, through this basis The hourly gas volume signal can obtain the start capture time T _X1 and the end capture time T _X2 corresponding to the final expiratory volume. Then, by comparing the initial capture time T _X1 and the end capture time T _X2 with the time-dependent concentration change results of carbon dioxide, the carbon dioxide concentration of the user’s last exhalation time interval can be obtained, and finally, The blood sugar assessment result can be obtained by comparing the carbon dioxide concentration result with the corresponding standard blood sugar concentration value.

When measuring the overall carbon dioxide concentration of the user's exhaled breath as the basis for evaluating the blood sugar concentration, the user's first exhaled gas also includes dead space gases from the oral cavity, respiratory tract, and bronchi, and these dead space gases Because there is no respiratory exchange between the lungs and the blood, it will affect the accuracy of the measurement of the carbon dioxide concentration. Therefore, the present invention only measures the carbon dioxide concentration of the user's exhalation at the end of the exhalation process. The expiratory volume is the last gas exhaled by the user during the entire exhalation process, so it can avoid the interference of the dead space gas on the measurement of the carbon dioxide concentration, and improve the accuracy of the measurement of the carbon dioxide concentration, so as to enhance the blood sugar assessment accuracy. It should be noted that the total expiratory volume (equivalent to vital capacity) will vary according to different ages and physiological conditions, and the terminal expiratory volume is based on the fact that it is not greater than 10% of the total expiratory volume.

The aforementioned first embodiment utilizes the result of continuous measurement of the time-dependent concentration of carbon dioxide in the exhaled breath of the user during the exhalation process, and then utilizes the carbon dioxide concentration in the final expiratory time interval to evaluate the blood sugar level. However, in actual implementation, it is not necessary to continuously measure the concentration of carbon dioxide in the exhaled gas, but to evaluate the results based on the data before the measurement, and only measure the concentration of carbon dioxide in the end-expiration time interval of the user. The purpose of the present invention can be reached equally. This method will be described in the following second embodiment.

Referring to FIG. 1 and FIG. 4 , the second embodiment of the blood glucose concentration assessment method of the present invention includes a pre-assessment step 60 , the breath capture measurement step 61 , and the blood glucose assessment step 62 .

The pre-evaluation step 60 is to use the detection device 200 to capture the exhaled gas exhaled by the user in the previous continuous time interval T ₀ ~T _n , and perform time integral calculation through the analysis unit 5 to obtain the used or the total expiratory volume and/or time-dependent gas flow in the continuous time interval T ₀ ~T _n , calculate the final expiratory volume through the total expiratory volume, and use the terminal expiratory volume to obtain a corresponding The last expiratory time interval, and obtain a preset start capture time and a preset end capture time of the last expiratory time interval.

Next, execute the exhalation capture measurement step 61, different from the first embodiment, since the pre-assessment step 60 has estimated the default initial capture of the user's final exhalation time interval time and the default end capture time, therefore, the gas capture measurement step 61 of the second embodiment is to combine the default start capture time and the default end capture time defined from the pre-assessment step 60 The capture time is used as the start capture time T _X1 and the end capture time T _X2 of the final expiratory volume of the current measurement, and it is only necessary to measure the user during the current exhalation process , the carbon dioxide concentration within the time interval of T _X1 ~ T _X2 is sufficient, and it is not necessary to continuously measure the carbon dioxide concentration of the gas exhaled by the user during the entire exhalation process. Finally, through the blood glucose assessment step 62 , the measured carbon dioxide concentration in the end-expiratory time interval can be compared with the corresponding standard blood glucose level to obtain a blood glucose assessment result.

In some embodiments, the pre-assessment step 60 may not need to actually measure, but calculate the preset initial acquisition time and The preset end capture time, wherein the preset value of the total expiratory volume and the preset value of the exhalation time are set according to one of the user's age, gender or other physiological characteristics, or an existing database .

The detection method in this case can evaluate the blood sugar status of the user by observing the overall change trend of the carbon dioxide concentration of the end-expiration measured by the user at different time points, for example: when the user eats, The carbon dioxide concentration in the final exhalation continued to increase over time, and there was no sign of decrease after about 2 hours, indicating that the user's blood sugar concentration was high, and the user may have insufficient glucose metabolism.

Referring to FIG. 3 , the relationship curve between the carbon dioxide concentration at the end of exhalation and the blood glucose concentration can be obtained by asking the user to perform an Oral glucose tolerance test (OGTT). First, let the user take 75 grams of glucose (glucose) on an empty stomach; then, within 120 minutes, let the user use the detection device 200 to measure the carbon dioxide concentration of the end-breath every 30 minutes, And at the same time measure the user's blood glucose concentration (see Table 1). Figure 3 shows the carbon dioxide concentration (solid line) and the blood glucose concentration (dotted line) of the user in the end-expiratory time interval measured at different time points before and after eating glucose during the glucose tolerance test. . It can be found from FIG. 3 that the carbon dioxide concentration in the last expiratory time interval is positively correlated with the blood glucose concentration. Therefore, through the measurement results of the carbon dioxide concentration in the end exhalation and the blood glucose concentration of the user, a relationship curve between the carbon dioxide concentration in the end exhalation and the blood glucose concentration can be established. Subsequently, the carbon dioxide concentration measured by the detection method of the present invention can be used to obtain the corresponding blood sugar concentration value through the interpolation method. Finally, the blood sugar concentration value is compared with a standard blood sugar concentration value to obtain the blood sugar evaluation result. For example, about 120 minutes after a general user eats, the standard blood sugar concentration value should not exceed 200 mg/dL. If the user eats for about 120 minutes, the blood sugar concentration value calculated from the carbon dioxide concentration in the end breath measured by the present invention is 210 mg/dL, which is exceeded after comparing with the standard blood sugar concentration value, then the use Patients may have insufficient glucose metabolism and should go to a medical institution for consultation as soon as possible. In addition, it should be noted that the corresponding relationship between the carbon dioxide concentration and the blood glucose concentration may also be obtained from an existing database.

Table 1 Concentration of CO2 in final exhalation (%) Blood glucose concentration value (mg/dl) 4.0~4.5 70~85 4.5~5.0 85~100 5.0~5.5 100~115 5.5~6.0 115~130

To sum up, the method for evaluating blood sugar concentration of the present invention extracts the last exhaled breath from the exhaled gas through the exhalation extraction step 61 to measure the concentration of carbon dioxide to perform blood sugar assessment, excluding those from the oral cavity, The interference of dead space gases such as the respiratory tract or bronchi improves the accuracy of blood sugar concentration assessment. In addition, the detection device 200 allows the user to perform blood sugar assessment in a non-invasive manner, and the detection process is simple, which is more conducive to blood sugar assessment. Carrying out, so can really reach the purpose of the present invention.

But the above-mentioned ones are only embodiments of the present invention, and should not limit the scope of the present invention. All simple equivalent changes and modifications made according to the patent scope of the present invention and the content of the patent specification are still within the scope of the present invention. Within the scope covered by the patent of the present invention.

200: detection device 2: Gas retention unit 21: Hollow tube body 211: air inlet 212: Exhaust port 22: Exhaust parts 3: Conversion unit 31:Audio frequency converter 32: Receiver 4: Sensing unit 41: Gas sensor 5: Analysis unit 60: Pre-assessment steps 61: Exhalation capture measurement steps 62: Blood sugar assessment steps

Other features and effects of the present invention will be clearly presented in the implementation manner with reference to the drawings, wherein: Fig. 1 is a schematic diagram illustrating an embodiment of the detection device of the present invention; Fig. 2 is a flowchart illustrating a first embodiment of the method for assessing blood sugar concentration of the present invention; Fig. 3 is a graph showing the relationship between the concentration of carbon dioxide in exhaled breath and the concentration of blood glucose, illustrating the relationship between the concentration of carbon dioxide in the user's exhaled gas and the concentration of blood glucose measured in the first embodiment; and FIG. 4 is a flowchart illustrating a second embodiment of the method for assessing blood glucose concentration of the present invention.

61: Exhalation capture measurement steps

62: Blood sugar assessment steps

Claims (10)

A method for assessing blood glucose concentration for a user to detect blood glucose concentration in a non-invasive manner, comprising: a breath capture measurement step, capturing a breath exhaled by the user in a continuous time interval T ₀ ~T _n The final expiratory volume of the breath gas, and measure the carbon dioxide concentration of the final expiratory volume, wherein, T ₀ is an exhalation start time, T _n is an exhalation end time, and the final expiratory volume is captured taken from a time interval between a start capture time T _X1 and an end capture time T _X2 , and T ₀ < T _X1 , T _X1 < T _X2 ≦ T _n , X1, X2, and n are natural numbers, and The terminal expiratory volume is not greater than 10% of the total expiratory volume in the continuous time interval T ₀ ~T _n ; and a blood sugar assessment step, using the carbon dioxide concentration of the terminal expiratory volume to calculate and estimate the user's blood sugar Concentration to obtain blood sugar assessment results. The method for assessing blood glucose concentration according to claim 1, wherein the blood glucose assessment step is to compare the blood glucose concentration estimated from the carbon dioxide concentration of the end expiratory volume with a standard blood glucose concentration value to obtain The blood sugar assessment result. The blood glucose concentration assessment method as described in Claim 1, wherein the breath capture measurement step is to obtain the time-dependent gas flow rate and total expiratory volume of the user’s expiratory gas in the continuous time interval, and the time-dependent concentration change result of the exhaled gas carbon dioxide in the continuous time interval, and determine the initial capture time T _X1 and the end capture time T _X2 of the final expiratory volume based on the total expiratory volume . The method for evaluating blood glucose concentration as described in Claim 1 further includes a pre-evaluation step, the pre-evaluation step is to obtain a preset start capture time and a preset end capture time for the user, The breath capture measurement step uses the preset start capture time and the preset end capture time as the start capture time T _X1 of the final expiratory volume, and the end capture time T _X2 , and only capture and measure the carbon dioxide concentration of the user at the end of the expiratory volume. The method for assessing blood glucose concentration as described in Claim 4, wherein the pre-assessment step is to measure the expiratory gas exhaled by the user in the previous continuous time interval, and obtain the total expiratory volume, and use the total expiratory volume to obtain the preset start capture time and the preset end capture time of the final expiratory volume, the breath capture measurement step starts from the preset The start capture time and the preset end capture time are used as the start capture time T _X1 and the end capture time T _X2 of the final expiratory volume of the expiratory gas exhaled by the user at the current time . The method for assessing blood glucose concentration as described in Claim 4, wherein the pre-assessment step is obtained by calculating a preset value of total expiratory volume and a preset value of exhalation time related to the preset value of total expiratory volume The default start capture time and the preset end capture time, the breath capture measurement step is to use the default start capture time and the default end capture time as the user at the time The start capture time T _X1 and the end capture time T _X2 of the terminal expiratory volume of the exhaled expiratory gas. The method for evaluating blood glucose concentration according to claim 6, wherein the preset value of the total expiratory volume and the preset value of the exhalation time are set according to one of the user's age, gender or other physiological characteristics. A detection device for a user to detect blood glucose concentration in a non-invasive manner, comprising: A gas entrapment unit comprising a hollow tubular body having an inlet for receiving exhalation gas exhaled by the user, and an air inlet remote from the inlet for expelling the exhalation gas exhaust vent; A conversion unit, including an audio frequency converter, the audio frequency converter is arranged in the hollow tube and communicated with the air inlet, the expiratory gas introduced from the air inlet can enter the audio frequency converter at the same time, the audio frequency conversion The device can convert the expiratory gas entering at different times into different sound wave signals according to the gas volume; A sensing unit is arranged in the hollow tube and includes at least one gas sensor for sensing the carbon dioxide concentration in the exhalation gas; and An analysis unit, which is respectively connected to the sensing unit and the conversion unit, uses the acoustic wave signals obtained at different times to calculate a time-dependent gas volume signal of the expiratory gas, and can use the result of the time-dependent gas volume signal The carbon dioxide concentration measured by the sensing unit in a specific time period is obtained. The detecting device according to claim 8, wherein the audio frequency converter is a whistle generator, and the conversion unit further includes a receiver, which is arranged adjacent to the audio frequency converter and used for receiving the sound wave signal. The detection device according to claim 8, further comprising an exhaust member, which communicates with the exhaust port of the hollow tube body and is used to force the expiratory gas entering the hollow tube body to be discharged outward .

Images