Abstract: A dehumidifier is connected to a respiratory gas measuring apparatus. A membrane dryer has a first flow path through which a respiratory gas of a subject passes, and a second flow path through which a purge gas passes. A first normally-closed electromagnetic valve is disposed in a first upstream flow path that communicates with the first flow path. A second normally-closed electromagnetic valve is disposed in a first downstream flow path that communicates with the first flow path. A third normally-closed electromagnetic valve is disposed in a second upstream flow path that communicates with the second flow path. A fourth normally-closed electromagnetic valve is disposed in a second downstream flow path that communicates with the second flow path.

Abstract: A dehumidifier is connected to a respiratory gas measuring apparatus. A membrane dryer has a first flow path through which a respiratory gas of a subject passes, and a second flow path through which a purge gas passes. A first normally-closed electromagnetic valve is disposed in a first upstream flow path that communicates with the first flow path. A second normally-closed electromagnetic valve is disposed in a first downstream flow path that communicates with the first flow path. A third normally-closed electromagnetic valve is disposed in a second upstream flow path that communicates with the second flow path. A fourth normally-closed electromagnetic valve is disposed in a second downstream flow path that communicates with the second flow path.

Abstract: An apparatus for determining sleep apnea includes: an expiratory gas collector which is configured to collect an expiratory gas of a subject; an analyzer which is configured to analyze a constituent and a concentration of the constituent in the collected expiratory gas; and a determiner which is configured to determine whether the subject is in sleep apnea or not, based on a concentration of at least VOC in the analyzed expiratory gas.

Abstract: A two-wavelength type respiratory gas concentration measuring device includes a connector tube which is held in the mouth of an examinee and which has airtight windows, a light source which applies infrared rays through the windows of the connector tube, and first and second filters. The first filter allows the transmission of a light component whose wavelength is such that it is absorbed by the respiratory gas, and the second filter allows the transmission of a light component whose wavelength is such that it is not absorbed by the respiratory gas. A photodetector converts the infrared rays transmitted through the filters into an electric signal. A first detector receives the electric signal and detects the light output of the first filter. A second detector receives the electric signal and detects the light output of the second filter. A power computing circuit performs a power computation of the output of the second detector with a power exponent m.

Abstract: A method of and apparatus for effecting artificial respiration in synchronism with a patient's voluntary breathing. The apparatus is in the form of an external body ventilator with an assistor, and comprises a jacket, a suction pump, a suction pipe, a changeover device, a jaw movement detection device, and a changeover controlling device. The jacket has a rigid shell for surrounding the chest of a patient and forming an air-tight chamber between the chest and the rigid shell when the jacket is applied to the chest of the patient. The suction pipe is in fluid communication with the air-tight chamber of the jacket, and the changeover device is for effecting a changeover between releasing the air in the air-tight chamber through the suction pipe and into the atmosphere during voluntary respiration, and connecting the suction pipe to the suction pump during artificial respiration.

Abstract: A measuring conduit adapted for flow rate and concentration of a fluid for use in a measuring apparatus which measures both the flow rate of the fluid such as a respiratory gas containing a particular gas component, for example, carbon dioxide, using an ultrasonic wave and the concentration of the particular gas component in an optical manner. In order to simultaneously measure the flow rate and concentration and also to reduce the dead space of the measuring conduit, this measuring conduit comprises a single conduit member through which the fluid flows; a pair of ultrasonic transducers attached to the conduit member so as to face each other along a line slanted with respect to a flow direction of the fluid; and a pair of light transmitting windows airtightly provided in the wall of the conduit member between the ultrasonic transducers so as to face each other. One of the light transmitting windows introduces a light beam from an external light source into the conduit member.

Abstract: A respiratory gas concentration measuring apparatus includes a chopper having a first filter for passing therethrough light from a light source and having a first wavelength which can be absorbed by a gas to be measured and a second filter for passing therethrough light from the light source and having a second wavelength which cannot be absorbed by the gas. The chopper is rotatable to position the first and second filters alternately in a light path. The light having passed through the filters is converted by a photodetector into an electric signal. A first detector detects an output from the first filter based on the electric signal, and a second detector detects an output from the second filter based on the electric signal.