JPH04115057U - exhalation monitor - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a small and handy exhalation monitor that can monitor carbon dioxide concentration in exhaled breath with high sensitivity in real time. [Configuration] Expanded diameter part 11 that covers the subject's nose and mouth on one end side
Also, a substantially funnel-shaped mask part 10 having a reduced diameter part 12 as an exhalation outlet on the other end side, a carbon dioxide detection sensor 20 disposed on the reduced diameter part 12 of this mask part 10, and a carbon dioxide detection sensor 20 disposed on the reduced diameter part 12 of this mask part 10. The sensor 20 is characterized in that it is composed of a drive circuit section 40 and a lead wire 30 that electrically connects the drive circuit section 40 and the carbon dioxide detection sensor 20.
It exhibits excellent functionality in medical applications, such as monitoring the respiratory status of critically ill patients and newborn babies, and sports applications, which track the amount of exercise of people exercising.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to an exhalation monitor that monitors the breathing state of living organisms. For more details, it is possible to monitor the carbon dioxide concentration in exhaled breath with high sensitivity in real time. The present invention relates to a small and handy exhalation monitor that is possible.

0002

[Conventional technology]

In general, the concentration of carbon dioxide contained in a living body's exhaled breath is determined by the rate of its pulse, etc. It is an important factor for understanding physical conditions and physical activity, especially for seriously ill patients. For infants and newborns, respiratory conditions can be determined by measuring the carbon dioxide concentration in exhaled breath. A judgment has been made regarding the status of

0003 Conventionally, the devices used to measure the carbon dioxide concentration in living organisms have been an expiratory flowmeter and a separate device. The carbon dioxide concentration is analyzed using a monitor mechanism consisting of an optical filter, and the carbon dioxide concentration is analyzed using a light control filter. Device that measures carbon dioxide concentration based on the output of the feedback circuit 31651) and nursery rooms for newborns, carbon dioxide absorbers, and heat-sensitive elements. A monitor mechanism equipped with children, etc. is connected with a pipe, and the air inside the nursery room is connected to a suction pump. A device for measuring carbon dioxide concentration by sending it to the monitor mechanism (Japanese Patent Laid-Open No. 62-286) Publication No. 53), etc. have been proposed.

0004 However, with the conventional measuring device described above, the device itself has become large and cost-effective. Also, it is not possible to measure at the subject's mouth, and it is difficult to actually measure using the monitor mechanism. Since the amount of carbon dioxide that can be determined is small, the exhaled breath of the subject is collected using a suction pump. There were problems such as the need to send the data to a monitor mechanism.

[0005]

[Problem that the idea aims to solve]

This invention solves the problems of the conventional carbon dioxide concentration measuring device mentioned above. This was achieved as a result of careful consideration.

[0006] Therefore, the purpose of this invention is to monitor the carbon dioxide concentration in exhaled breath in real time. A small and handy exhalation monitor that can be monitored at any time. Our goal is to provide the following.

[0007]

[Means to solve the problem]

In order to achieve the above purpose, the exhalation monitor of this invention has one end attached to the subject's nose. It is approximately funnel-shaped, with an enlarged diameter part that covers the mouth and a reduced diameter part that serves as an exhalation outlet on the other end. A mask part, a carbon dioxide gas detection sensor disposed in the reduced diameter part of this mask part, and this A drive circuit section of a carbon dioxide gas detection sensor, and this drive circuit section and the carbon dioxide gas detection sensor. and a lead wire for electrically connecting them.

[0008]

[Effect]

The exhalation monitor of this invention consists of a mask part and a carbon dioxide sensor placed in the reduced diameter part of this mask part. A gas detection sensor, a drive circuit for this carbon dioxide gas detection sensor, and a drive circuit for this carbon dioxide detection sensor. Since it consists of a lead wire that electrically connects the carbon dioxide gas detection sensor, it is small. It is a small and handy type, and just by placing the mask on the patient's mouth, the Real-time measurement of carbon dioxide concentration in exhaled breath without the need for other parts such as a pump can be monitored with high sensitivity at any time.

[0009] In addition, according to the breath monitor of this invention, an ionic conductor is used as a carbon dioxide sensor. A sensing electrode and a reference electrode are placed opposite each other, and an alkaline earth metal is placed on the sensing electrode. A sensor coated with a sensing material layer consisting of a solid solution of carbonate and alkali metal carbonate. By using this method, the electromotive force characteristics for carbon dioxide gas are influenced by the moisture in the exhaled breath of the subject. Monitors the carbon dioxide concentration in exhaled breath with high response and sensitivity. It is possible to

0010

【Example】

The following is a detailed explanation of an embodiment of the breath monitor of this invention with reference to the drawings. do.

[0011] Figure 1 is a partially cutaway side view showing an embodiment of the exhalation monitor of this invention, and Figure 2 is Figure 1. Figure 3 shows the carbon dioxide gas detection used in the exhalation monitor of this invention. A cross-sectional view of the sensor, FIG. 4 is a partially cutaway side showing another embodiment of the exhalation monitor of this invention. 5 is an explanatory diagram of the output signal processing circuit used in the breath monitor of this invention, and FIG. 6 is a top view. It is a figure which shows the example of a measurement using the exhalation monitor of this invention.

0012 As shown in Figs. 1 and 2, the exhalation monitor of this invention has a test subject attached to one end. It has an enlarged diameter part 11 that covers the nose and mouth, and a reduced diameter part 12 as an exhalation outlet on the other end side. A substantially funnel-shaped mask portion 10 and carbonic acid disposed in the reduced diameter portion 12 of this mask portion 10. The gas detection sensor 20, the drive circuit section 40 of this carbon dioxide detection sensor 20, and this From a lead wire 30 that electrically connects the drive circuit section and the carbon dioxide gas detection sensor. It is configured.

[0013] The mask part 10 is made by molding lightweight and elastic rubber or plastic. It is preferable that the enlarged diameter portion 11 has a diameter that covers the subject's nose and mouth. It is designed to be large enough to send the exhaled air of this subject to the reduced diameter section 12. It is desirable that

[0014] In addition, the mask portion 10 may be hooked onto the patient's ear to stabilize the mask portion 10. A belt-like holder 13 is provided for fixing. This holder 13 is In addition to the one shown, there is also a stand-like structure that allows the mask part 10 to be fixed and placed on the subject's mouth. It may be of.

[0015] The carbon dioxide detection sensor 20 is attached to the reduced diameter portion 12 of the mask portion 10 using a fixing device such as a metal fitting. It is attached by 21.

[0016] The lead wire 30 connected to the carbon dioxide gas detection sensor 20 is connected to the sensor drive circuit section 40. is electrically connected to the carbon dioxide gas detection sensor 20 and supplies power for generating heat to the carbon dioxide gas detection sensor 20. At the same time, the electric signal detected by the carbon dioxide gas detection sensor 20 is transmitted to the sensor drive circuit section 4. 0 and the output signal processing circuit 50 provided as necessary. There is.

[0017] FIG. 3 shows an example of the structure of the carbon dioxide gas detection sensor 20 used in this invention.

[0018] In FIG. 3, 20 is a carbon dioxide gas detection sensor, and 21 is a detection electrode. This detection The electrode 21 is made of, for example, an alkaline earth metal carbonate and an alkali metal mesh on a platinum mesh coated with platinum black. It is coated with a sensing material layer 22 made of a solid solution with potassium metal carbonate.

[0019] 23 is a solid electrolyte, and 24 is a reference electrode on which, for example, platinum black is attached. It is made of a platinum wire mesh, and is covered with glass or other material to shield it from the test gas (exhaust gas). It is covered with a cover 27 and sealed. In addition, 25 is a ceramic substrate, 26 is a heater made of a platinum film provided on the back surface of the substrate.

[0020] Alkaline earth forming the sensing material layer 22 made of solid solution in the sensing electrode 21 Metal carbonates include calcium carbonate, strontium carbonate, and barium carbonate. These are preferably used, and not only one type but two or more types may be used. difference In addition, alkali metal carbonates include lithium carbonate, sodium carbonate, and carbonate. Potassium etc. are preferably used, and these can be used not only alone but also in combination of two or more. good. Therefore, as the sensing electrode 21, an alkaline earth metal carbonate as described above is used. Solid solutions with alkali metal carbonates, especially crystal-free solid solutions of alkali metal carbonates By using a material coated with the sensing material layer 22 made of body, it is possible to detect carbon dioxide gas. The electromotive force characteristics for It becomes possible to monitor acid gas concentration with high response and high sensitivity.

[0021] Examples of the solid electrolyte 23 include β-alumina, sintered body of NASICON, etc. Any suitable sodium ion conductor can be used. In addition, the reference electrode 24 has For example, a material made of platinum mesh coated with platinum black is used, and in some cases, Similar to the detection electrode 21, a solid solution of alkaline earth metal carbonate and alkali metal carbonate It may be coated with. Such a reference electrode 24 is covered with a cover and exposed to the sample gas. It is preferable not to be affected by the concentration of carbon dioxide therein.

[0022] The carbon dioxide gas detection sensor 20 configured as described above can be heated from 400°C to 600°C. Detection is performed in response to the partial pressure of carbon dioxide in the sample gas that is heated and comes into contact with the detection electrode 21. By measuring the electromotive force generated between the electrode 21 and the reference electrode 24, the The carbon dioxide concentration in the gas can be detected accurately.

[0023] Further, FIG. 4 shows another embodiment of the exhalation monitor of this invention, in which the diameter of the mask portion 10 is reduced. The exhaled air of the subject is placed closer to the enlarged diameter portion 11 than the carbon dioxide gas detection sensor 20 in the portion 12. In addition to providing a check valve 14 that opens accordingly, an intake port 15 is provided in a part of the mask portion 10. This point is different from the embodiment shown in FIGS. 1 and 2 above.

[0024] According to this embodiment, the check valve 14 that opens in response to exhalation of the subject is arranged. The exhaled breath of the subject can be accurately sent to the carbon dioxide detection sensor 20, In addition, the fresh outside air inhaled from the air supply port 15 may cause breathing difficulties for the subject. No more worries. Note that it is not necessary to provide both the check valve 14 and the air supply port 15. It is also possible to provide only one of them and expect the performance of each.

[0025] Furthermore, especially when the subject is a critically ill patient who requires oxygen inhalation, etc. By connecting an oxygen cylinder to the air supply port 15, inhaled oxygen and exhaled charcoal can be combined. The patient's medical condition can be determined from the acid gas concentration.

[0026] FIG. 5 shows an output signal processing circuit 50 to which the breath monitor of this invention is connected. Detected by the gas detection sensor 20 and output from the sensor drive circuit section 40 to the signal processing circuit 5 The output signal input to 0 is first pulse-shaped and then frequency-voltage converted. After that, for example, a determination is made as to whether there is an abnormality, and if there is an abnormality, an alarm will be sent. For example, this system is set up so that nursing care for critically ill patients and monitoring of their condition can be performed at night, for example. Able to effectively carry out handholding.

[0027] In addition, the exhalation monitor of this invention can be used for the above-mentioned critically ill patients, bedridden elderly, and Not only can it be effectively used for medical purposes such as understanding the medical conditions of infants and newborns, but it can also be used for sports. For those who exercise, it is a simple measurement to monitor the amount of exercise during and after exercise. It can also be effectively used as a fixture.

[0028] In other words, the conventional means of monitoring the amount of exercise is to detect the amount of exercise from exercise equipment. Previously, detection was performed based on the number of expiratory breaths and heart rate, but with this devised expiratory monitor, , measures the carbon dioxide concentration in exhaled breath during and after exercise, and displays the measurement results immediately. If it can be displayed, it will be useful for the patient in conjunction with other monitoring results such as number of nights per night. It is possible to understand the optimal amount of exercise by using It is Noh.

[0029] Therefore, the breath monitor of this invention is small and handy as mentioned above. In addition, it has the ability to fully respond to the recent health boom. I can say that.

[0030]

[Effect of the idea]

As explained above, the breath monitor of this invention is small and handy. Realistic measurement of carbon dioxide concentration in exhaled breath without the need for other parts such as a suction pump It is possible to monitor the time with high sensitivity.

[0031] Therefore, the breath monitor of this invention takes advantage of its excellent functions and is suitable for medical use. It can be expected to be widely used for sports and other applications.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view showing an embodiment of the exhalation monitor of this invention.

FIG. 2 is a back view of the mask section in FIG. 1;

FIG. 3 is a sectional view of a carbon dioxide detection sensor used in the breath monitor of this invention.

FIG. 4 is a partially cutaway side view showing another embodiment of the breath monitor of this invention.

FIG. 5 is an explanatory diagram of an output signal processing circuit used in the exhalation monitor of this invention.

FIG. 6 is a diagram showing an example of measurement using the breath monitor of this invention.

[Explanation of symbols]

10 Mask part 11 Expanded diameter part 12 Reduced diameter part 20 Carbon dioxide gas detection sensor 30 Lead wire 40 Sensor drive circuit section

Claims (4)

[Scope of utility model registration request] 1. A substantially funnel-shaped mask portion having an enlarged diameter portion covering the nose and mouth of the subject at one end and a reduced diameter portion serving as an exhalation outlet at the other end; It is characterized by being composed of a carbon dioxide gas detection sensor disposed in the diameter portion, a drive circuit section for the carbon dioxide gas detection sensor, and a lead wire that electrically connects the drive circuit section and the carbon dioxide detection sensor. Breath monitor. 2. A carbon dioxide gas detection sensor includes a detection electrode and a reference electrode disposed opposite to each other with an ionic conductor in between, and the detection electrode is made of a solid solution of an alkaline earth metal carbonate and an alkali metal carbonate. The exhalation monitor according to claim 1, characterized in that the material layer is coated. 3. Claims 1 and 2, characterized in that a check valve that opens in response to the subject's exhalation is provided on the side of the enlarged diameter part of the reduced diameter part of the mask part rather than the carbon dioxide gas detection sensor. The exhalation monitor described in . 4. The exhalation monitor according to claim 1, wherein a part of the mask portion is provided with an intake port.