JPH10288615A - Exhalation metabolism measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to measure exhalation without using a mask and a hose by applying light on the part of an organism, wherein the exhalation passes, and measuring the amount of the exhalation component from the change in the amount of received light caused by the exhalation passing the organism. SOLUTION: This device is constituted of a light emitting means 1, a light receiving means 2 and an analyzing means 3. As the light emitting means 1, a light emitting diode, which emits the wavelength in the near infrared ray region having, e.g. high organism transmission property, is used. As the light receiving means 2, a photo-diode is used. When the transmitting light is used, the light emitting means 1 and the light receiving means 2 are mounted on the mutually opposite sides with respect to the organism part, wherein the exhalation passes, e.g. the center of the neck. When the light is applied from the light emitting means 1, the wavelength component peculiar to CO2 contained in the exhausting exhalation is strongly absorbed. Then, the light received with the light receiving means 2 is analyzed with the analyzing means 3, and the absorbancy at this wavelength is obtained. Thus, the CO2 concentration is specified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breath measurement apparatus for measuring a predetermined component or respiratory rate in expired air exhaled from a living body.

[0002]

2. Description of the Related Art Conventionally, as a breath metabolism measuring device, the United States
Sensor Medix device (approval number: 04B Transport 11
32) are known.

[0003] FIG. 3 shows the structure of a conventional breath metabolism measuring apparatus. The expired breath is collected by a mask 11 that completely covers the mouth, and the collected breath is guided to a measuring apparatus 13 by a hose 12. Therefore, the measurement of carbon dioxide concentration has been performed by an infrared absorption method or the like.

[0004]

Generally, in a breath measurement apparatus, the breath to be emitted from the mouth to the outside of the body is to be measured. For this reason, a method of collecting exhaled air is required, and a mask and a hose that completely cover the mouth are used, which causes pain to the subject and strongly restrains the living body.

[0005] It is an object of the present invention to provide a breath measuring apparatus that does not cause pain to a subject who does not use a mask or a hose without restraining the movement of a living body.

[0006]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention measures an expired gas passing through a living body using an optical measuring device mounted so that light propagates inside the living body through which the expired gas passes.

[0007]

Embodiments of the present invention will be described below. Although there are various methods for carrying out the present invention, a measuring method using transmitted light intensity of light will be described as one of the realization examples. FIG. 1 shows an overall schematic diagram.

According to FIG. 1, the apparatus comprises a light emitting means 1, a light receiving means 2, and an analyzing means 3. For example, as the light emitting means 1, a light emitting diode which emits near-infrared wavelengths having high biological permeability, a light receiving means 2 Can be used as a photodiode. As shown in FIG. 1, when these are attached to a living body part through which exhalation passes, for example, a neck or the like and transmitted light is used, for example, a light emitting unit 1 and a light receiving unit 2 are provided on opposite sides of the center of the neck. Attach.

[0009] As an example, suppose that CO ₂ is measured as a breath component. CO ₂ is a component contained in the exhaled breath exhaled by the living body that has inhaled oxygen, and the wavelength component specific to this CO ₂ is strongly absorbed in the light incident on the living body from the light emitting means 1. Therefore, by determining the absorbance at this wavelength by the analyzing means 3 for the light detected by the light receiving means 2, the CO ₂ concentration can be specified.

For the measurement of the absorbance, for example, a plurality of light emitting diodes having different wavelengths are used as the light emitting means 1, and the following outputs are obtained from the light receiving means 2 corresponding to these different wavelengths. Analysis means 3 is performed.

For example, assuming that the incident light amount is I ₀ , the light amount after passing through the living body is I, the absorption coefficient ε, and the concentration of each component C _i , the Lambert-Beer rule is log (I ₀ / I) = は C _i Ε _i, which is solved as a simultaneous equation for a plurality of wavelengths by the analysis means 3 to obtain the concentration of the desired component.

It can be easily analogized that this can also be realized by using a standard light source as the light emitting means and using a multi-channel detector as the light receiving means.

FIG. 2 shows a typical measurement result of the CO ₂ concentration thus obtained. FIG. 2 shows that CO ₂ periodically decreases and increases with time in accordance with the respiration of the living body. From this figure, CO ₂
If the decrease / increase of is counted as one breath, the respiratory rate can be calculated.

Although CO ₂ has been described as an embodiment, it is obvious that CO ₂ can be measured in a similar manner even if other components are used. Also, not only the transmitted light,
It is clear that the measurement can be performed using diffused light and transmitted diffused light.

[0015]

As described above, according to the present invention, the breath can be measured non-invasively without the trouble of carrying a mask for closing the mouth of the subject or a hose for introducing the breath into the analyzer. Effects can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a breath measurement device.

FIG. 2 is a diagram showing a time change of a measured CO2 concentration.

FIG. 3 is a schematic diagram of a conventional breath measurement device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light-emitting part 2 Light-receiving part 3 Analysis part 11 Mask 12 Hose 13 Analysis device

Claims (4)

[Claims] 1. An apparatus comprising at least one light emitting means and at least one light receiving means, wherein light emitted from the light emitting means is made incident on a living body part through which exhaled breath passes, and light emitted from the light is emitted to the light receiving means. An exhalation metabolism measuring apparatus for measuring the amount of at least one exhalation component from a change received by exhalation passing through a living body, detected by the method. 2. At least one light-emitting means and at least one light-receiving means, wherein light emitted from the light-emitting means is made incident on a living body part through which exhaled breath passes, and light emitted from the light is received by the light-receiving means. An exhalation metabolism measurement device that measures the respiratory rate from changes received by exhaled air that passes through the living body. 3. A living body, comprising: at least one light emitting means; and at least one means for detecting a sound wave, wherein light emitted from the light emitting means is incident on a living body portion through which exhaled breath passes, A breath metabolism measuring device for measuring the amount of at least one breath component by a photoacoustic signal depending on at least one component of the breath passing through the apparatus. 4. A living body, comprising: at least one light emitting means; and at least one means for detecting at least one sound wave, wherein light emitted from the light emitting means is made incident on a part of a living body through which exhaled breath passes, and the living body is generated by the light. An apparatus for measuring respiratory metabolism, which measures a respiratory rate by a photoacoustic signal depending on at least one component of expired air passing through the apparatus.