JPH07222733A - Method for measuring gaseous phase system respiratory function and method for managing health of gaseous phase system respiratory function using result of the measurement - Google Patents

Abstract

PURPOSE:To provide a method for managing health of a gaseous phase system respiratory function meeting a change of living habits by generally measuring the gaseous phase system respiratory function by using an inhalation gas distribution rate, residual air gas rate, carbon monoxide lung diffusing capacity and oxygen consumption demand index and using the results thereof. CONSTITUTION:A testee holds a pipe in his mouth and sucks the air contg. the carbon monoxide of a known concn. of about 0.3% (concn. F1(CO)) and helium of a known concn. of about 10% (concn. F1(He)) as much as possible. A suction amt. V1 is measured and after the testee is ordered to stop the respiration for about 10 seconds (t second), the testee is instructed to exhalate the air as much as possible. The residual amt. exclusive of a part having a possibility of mixing with the first dead space gas of the exhalated gas is drawn and the concn. FE(CO) of the carbon monoxide and the concn. FE(He) of the helium in the drawn gas are measured. The absorbed gas distribution rate FE(He)/F1(He)%, simple residual air rate RV'%, carbon monoxide lung diffusion capacity DL(CO) and oxygen consumption demand index DELTAP(CO)/t are calculated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring gas phase respiratory function and a method for health management of gas phase respiratory function using the results.

[0002]

2. Description of the Related Art Conventionally, there is no method for evaluating a gas phase respiratory function using an intake air gas distribution rate, a simple residual air rate, and an oxygen consumption demand index.

Conventionally, only the lung diffusion capacity of carbon monoxide has been measured, and this has been used for disease management of gas phase respiratory function.

[0004]

In such a conventional technique, it is possible to manage the disease by knowing how much oxygen gas in the alveoli diffuses and moves to the pulmonary capillaries, but it is possible to easily control the disease in the alveoli. It is not possible to judge the degree of residual air ratio, which is aimed at how the air is distributed in the body, and the oxygen consumption requirement in the peripheral tissues and organs of the body.
It is not suitable for health management of healthy people by improving diet, exercise, obesity, smoking).

An object of the present invention is to provide a method for generally measuring gas phase respiratory function, and to provide a health management method for gas phase respiratory function corresponding to changes in lifestyle by using these methods. Is.

[0006]

The present invention provides a subject with a known concentration of about 0.3% carbon monoxide (concentration F _I (CO)).
And a known concentration of about 10% helium (concentration F _I (H
e)) The air including and is sucked in as much as possible, the suction amount (V _I ) is measured, the breath is stopped for about 10 seconds (t seconds), and then the air is exhaled as much as possible, and the first exhalation gas is exhaled. Of the dead space gas excluding the part that may be mixed, and the concentration of carbon monoxide (F _E (C _E
O)) and helium concentration (F _E (He)) and is measured,
Intake gas distribution rate F according to equation 1, equation 2, equation 3 and equation 4
_{E (He) / F I (} He)%, and characterized by calculating a simple Zankiritsu RV '%, carbon monoxide lung diffusion capacity D _L (CO) and oxygen consumption demand level index ΔP (CO) / t It is a method of measuring the gas phase respiratory function.

[0007]

[Equation 2]

However, P _B is the atmospheric pressure (unit Torr). Further, according to the present invention, the intake gas distribution ratio F _E (He) / F _I (H
e)%, simple residual rate RV '%, carbon monoxide lung diffusion capacity D
_L (CO) and oxygen consumption demand index ΔP (CO) / t
Is a method of health management of gas phase respiratory function in response to changes in lifestyle habits.

[0009]

According to the present invention, the gas phase respiratory function is comprehensively judged by the inhalation gas distribution rate, the residual air rate, the carbon monoxide lung diffusing capacity and the oxygen consumption requirement index.

It is preferable that when the outside air is inhaled into the lung, the lung is filled with fresh air. However, the distribution of gas in the lungs becomes uneven, the concentration of inhaled gas is low, and residual air that is not exhaled by breathing remains. Respiratory function is determined not only by the absolute amount of residual air (remaining air volume RV), but also by the ratio of the total air volume (alveolar air volume V _A ) and the remaining air volume (remaining air volume RV%) during inhalation. Involved. The residual air volume RV and the alveolar air volume _VA are not the volumes during normal breathing but the volumes during the maximum inspiration and expiration.

RV% = (RV / V _A ) × 100 (5) Since it is difficult to directly determine the alveolar volume V _A and the residual volume RV, it does not change in the lung and From the above, a simple alveolar volume V _A ′ and a simple residual air amount RV ′ are obtained using an inert gas that hardly diffuses into the pulmonary capillaries, for example, air containing helium. That is, the helium concentration F _I (He)
Air was V _I intake, which as it becomes helium concentration of F _A (He) in the lungs and death腔気amount regarded as 0,

[0012]

[Equation 3]

Since the concentration of helium hardly changes in the alveoli, the helium concentration F _E (He) in exhaled air is F _A
It is approximately equal to (He). Further, since the simple residual air amount RV 'is the difference between the simple alveolar air amount V _A ′ and the inspiratory amount V _I , RV ′ = V _A ′ −V _I (7) From equations 5, 6 and 7, Equation 2 is introduced into.

[0014]

[Equation 4]

The simple residual air ratio RV '% is an inhaled air gas distribution ratio F _E (He) / F _I (He) which is a substitute index for the distribution of gas in the lungs.
Related to%. The residual air ratio RV% (and the simple residual air ratio RV '% is almost the same) is related to the vitality of the respiratory muscles and becomes smaller in a person who exercises well. Since the vitality of the respiratory muscles declines with age, the residual air ratio RV% may exceed 40% in the elderly.

Next, consider gas exchange in the lungs.
The airway enters the lung from the trachea through the bronchus, branches into many branches, and reaches the respiratory bronchiole RB, alveolar tract D, and alveolar sac S via the terminal bronchiole TB as shown in FIG. There is. The terminal bronchioles TB and a part of the respiratory bronchioles RB, which are represented by double lines, do not exchange gas, but the rest of the respiratory bronchioles RB, the alveolar passage D, and the alveolar sac S exchange gas. It is composed of a permeable alveolar membrane, which is surrounded by pulmonary capillaries. FIG. 2 schematically shows these relationships, in which respiratory bronchioles RB and below for gas exchange are represented by alveoli 1, and the alveolar membrane 5 and pulmonary capillaries 2 are in contact with each other. Inhalation enters the alveoli 1 from the terminal bronchioles 3, exchanges oxygen and carbon gas through the alveolar membrane 5 and the tube membrane 4 of the pulmonary capillaries 2, and is exhaled from the terminal bronchioles 3 to the outside as exhaled air. It When the gas permeates the alveolar membrane 5 and the vascular membrane 4, the permeation resistance is determined by the gas, but the smaller the molecular weight, the smaller the permeation resistance. Particularly, carbon gas has a small permeation resistance of about 1/20 that of oxygen, and is not a problem. Helium has a small molecular weight and has a large permeation resistance, so it is considered that helium hardly permeates.

Oxygen in blood is divided into a portion physically dissolved in blood and a portion bound to hemoglobin in blood. The amount dV / dt of oxygen that permeates the alveolar membrane and the pulmonary capillary membrane in a unit time is determined by the partial pressure of oxygen P ₁ (O ₂ ) in the alveoli and the blood in the pulmonary capillaries. It is proportional to the difference with the partial pressure P ₂ (O ₂ ) of oxygen.

DV / dt = D _L (O ₂ ) {P ₁ (O ₂ ) −P ₂ (O ₂ )} (8) D _L (O ₂ ) is called oxygen lung diffusion capacity, Since it is difficult to measure the partial pressure P ₂ (O ₂ ) of oxygen dissolved in blood, the pulmonary diffusion ability is almost equal to that of oxygen, and the binding force with hemoglobin in blood is sufficiently larger than that of oxygen. Therefore, the lung diffusion capacity is required for carbon monoxide, which is considered to have a partial pressure of almost zero dissolved in the blood as a gas. Therefore, carbon monoxide lung diffusion capacity D _L (C
Using O), equation 8 becomes equation 9 below.

DV / dt = D _L (CO) × P ₁ (CO) (9) Since V is the amount of carbon monoxide in the alveoli, dV = V _A × dF _A (CO) ( 10) Although the total pressure in the alveoli is equal to the atmospheric pressure P _B , the concentration of each gas is displayed as the concentration of dry gas, so (P _B −47) is the pressure of dry gas in the alveoli. Here, 47 is the saturated water vapor pressure at 37 ° C. (unit Torr). It is considered that the alveoli are saturated with water vapor, and the average human body temperature of 37 ° C is used. Thus, P ₁ (CO) = (P _B −47) × F _A (CO) (11) Substituting equations 10 and 11 into equation 9,

[0020]

[Equation 5]

Integrating both sides for t = 0 to t

[0022]

[Equation 6]

Here, F _A (CO) _O is the concentration of carbon monoxide in the alveoli at the initial stage (t = 0), and F _A (CO) _O = F _I (CO) × in the same idea as helium. (V _I / V _A ).
Further, F _A (CO) _t is the concentration of carbon monoxide in the alveoli at the final stage, and is equal to the concentration F _E (CO) of carbon monoxide in the exhaled breath.
Further, by substituting the equation 6 into V _A , the equation 13 becomes as follows.

[0024]

[Equation 7]

Equation 3'expresses D _L (CO) in seconds (ml / s)
ec · Torr), which is multiplied by 60 to express it in minutes (ml / min · Torr) is Equation 3.

Carbon monoxide lung diffusion capacity (D _L (CO)) is used as a comprehensive gas exchange index. The decrease may be due to uneven ventilation distribution or alveolar membrane thickening.

Oxygen consumption demand index (ΔP (CO) / t)
Is expressed by Equation 4 below.

[0028]

[Equation 8]

This represents the transition of the gas exchange state in the alveoli, which is the partial pressure difference of carbon monoxide per unit time, and the unit is mTorr / sec. The first term of Equation 4 (0.30 /
F _I (CO)) is a concentration of carbon monoxide in the intake gas of 0.
This is a term to be corrected to 30 (%). Item 2 (P _B -47)
Is the total dry gas pressure in the lung as explained above. First half of the third term {F _I (CO) × F _E (He) / F _I
(He)} is the concentration of carbon monoxide in the lung at the initial stage (t = 0) described above, and the latter half F _E (CO) is the concentration of carbon monoxide in the lung at the end stage. Multiplying these by (P _B -47) gives the partial pressures of carbon monoxide in the lung in the early and late stages. The numerator 10 of the fourth term is the pressure T
10 to change from orr to mTorr
It is multiplied by 00 and divided by 100 because the gas concentration is expressed in%, that is, 1000/100 = 10.

The oxygen consumption requirement index increases or decreases depending on the difference in lifestyle based on oxygen consumption. That is, it becomes higher in a person with a high degree of obesity, a person who eats a lot, and a person who exercises a lot. It is also lower in people with smoking habits and organ disorders. A person with a drinking habit usually has a higher oxygen consumption demand index (a drinking habit of about 1 go), but a person with a drinking habit of 3 to 4 or more for a long period of time or a person with a liver disorder does the opposite. Get lower.

By comprehensively judging and evaluating the inhaled gas distribution rate, the residual rate, the carbon monoxide lung diffusing capacity and the oxygen consumption requirement index, it is possible to provide appropriate guidance on the maintenance and management of the gas phase respiratory function. By measuring this again after a certain period (for example, 2-3 months), it is possible to give guidance from the viewpoint of lifestyle management.

This test is characterized in that it can be performed while taking normal breathing. For this reason, the concentration of carbon monoxide in the test gas is lowered to about 0.3%. Since the ability of carbon monoxide to bind to hemoglobin in blood is about 200 times that of oxygen, the concentration at which there is no danger of gas poisoning by carbon monoxide is 0.1% of 1/20 of the oxygen concentration in inspiration. In a short time test, up to 0.3% is acceptable. The helium concentration of the test gas is set to about 10% in order to obtain an acidity concentration that does not interfere with normal breathing using air.

[0033]

The present invention will be described in more detail below with reference to examples.

FIG. 3 is a diagram schematically showing an example of the apparatus used in the present invention. This device includes a pipe 17 held by a subject in a mouth by a switching valve 11, a respirometer 12 for storing an inspiratory test gas, and a device 1 for metering and discharging dead space gas.
3, inhalation gas collector 14 for analysis or outside air breathing tube 15
Switch between either.

The subject 18 breathes the outside air from the tube 15 through the switching valve 11 while holding the tube 17 in the mouth and holding the nose.
Before starting the test, the gas in the lungs 19 is exhaled as much as possible, the respirometer 12 and the tube 17 are connected by the switching valve 11, and the inhaled test gas is sucked in as much as possible, and the amount thereof is measured. When the inhalation ends, the breathing is stopped for 10 seconds, and the switching valve 11 is switched to call the device 13 for metering and discharging the dead space gas and then the device 14 for collecting the exhaled gas for analysis. When the call ends, the switching valve connects the pipe 17 to the pipe 15 to perform normal breathing. All the gas with which the dead space gas may mix is pumped to the device 13. The analytical exhaled gas is collected in device 14 and analyzed for carbon monoxide and helium. The switching of the switching valve 11 may be performed by a processing device implemented by a microcomputer or the like, but it is preferably performed manually while observing the condition of the subject. This test is usually performed 3 times and the average value is used.

Next, the experimental results of the present inventors will be described. The test subject is a healthy adult male. The intake test gas was air containing 0.3% of carbon monoxide and 12% of helium, and the intake amount of the test gas was 3198 ml. In addition, carbon monoxide in exhaled gas is 0.0875% and helium is 7.8%.
Met. Atmospheric pressure at the time of test was 760 Tor
r, the temperature is 20 ° C., and the standard state conversion coefficient is 0.826.

From Equation 1, the intake gas distribution ratio

[0038]

[Equation 9]

From equation 2, the simple residual air ratio RV '% is calculated as follows.

[0040]

[Equation 10]

From equation 3, carbon monoxide lung diffusivity D _L (C
O) is calculated as follows.

However, the intake amount is 760 Torr, 20 ° C.
Since this is measured at, convert this to 760 Torr and 0 ° C.

[0043]

[Equation 11]

From equation 4, the oxygen consumption demand index ΔP (CO)
/ T is calculated as follows.

[0045]

[Equation 12]

Further, the subject's obesity degree (BMI), eating habits (how to eat, eating time), food amount (total intake, green and yellow vegetable intake), drinking habits (one-time drinking amount, weekly drinking amount, drinking years) ), Exercise habits (exercise intensity, one exercise time, weekly exercise time), smoking habits (BI-Brickman index), organ disorders and their medical history, etc., and comprehensive health management is performed. In addition, the same test will be conducted 2-3 months later, and effective and appropriate health guidance will be given by comparing with the previous test result.

[0047]

According to the present invention, the intake gas distribution ratio and
Measures simple residual rate, carbon monoxide lung diffusion capacity, and oxygen consumption demand index, comprehensively judges gas phase respiratory function, and provides effective and appropriate health guidance to healthy people. You can manage your health.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a terminal portion of a trachea and alveoli.

FIG. 2 is a diagram schematically showing a state of gas exchange between alveoli 1 and capillaries 2.

FIG. 3 is a diagram showing an example of an apparatus used for measuring a gas phase respiratory function of the present invention.

[Explanation of symbols]

 1 Alveoli 2 Capillaries 11 Switching Valve 12 Respirator 14 Exhaled Gas Collection Device 17 Tube 18 Subject 19 Lung

Claims (2)

[Claims] 1. Air containing to a subject a known concentration of about 0.3% carbon monoxide (concentration F _I (CO)) and a known concentration of about 10% helium (concentration F _I (He)). is much suction possible, suction amount (V _I) is measured and after about 10 seconds (t in seconds) between the breathing is stopped, so called many as possible air, the first dead space gas call gas mixture possible to collect remaining except for portions of the carbon monoxide collecting gas concentration (F _E (CO)) and helium concentration (F _E (H
e)) is measured, and carbon monoxide lung diffusion capacity D _L (CO)
In the process of calculating
_{E (He) / F I (} He)%, simple Zankiritsu RV '%, and the measurement method of vapor respiration function and calculates the oxygen consumption demand level index ΔP (CO) / t. [Equation 1] However, P _B is atmospheric pressure (Unit Torr) 2. The intake gas distribution ratio F _E (He) / F _I (H
e)%, simple residual rate RV '%, carbon monoxide lung diffusion capacity D
_L (CO) and oxygen consumption demand index ΔP (CO) / t
A method for health management of gas phase respiratory function, characterized by using.