RU67450U1 - CAPNOGRAPHY APPARATUS - Google Patents

Abstract

The utility model relates to medical equipment, in particular, to diagnostic equipment, and can be used for functional diagnostics. The technical result achieved using the utility model is to increase the accuracy of measurements while expanding the diagnostic capabilities of the device. The apparatus for capnography includes a remote transducer, which is a measuring chamber, interchangeable elements (heat exchanger, cover, sleeve, funnel), while in the measuring chamber there is an ultrasonic transducer for determining the concentration of carbon dioxide and a heater with a temperature sensor, which are electrically connected to the measuring unit containing thermal stabilization unit, excitation path, registration path, analog-to-digital converter, non-volatile memory module for storage capnograms, microprocessor and display unit, and the measuring unit itself through the interface can be connected to a personal computer. 1 ill.

Description

The utility model relates to medical equipment, in particular, to diagnostic equipment, and can be used for functional diagnostics.

As the closest analogue of the claimed apparatus, the apparatus for carrying out capnography "Normocap Oxy-200", Datex company, containing a transducer for measuring carbon dioxide concentration, located in the apparatus body and a system for delivering a gas sample to the transducer, consisting of a sampler, compressor, electromagnetic valves, is selected in addition, there is a measuring unit containing an analog-to-digital converter and an indication system [1].

The disadvantages of this apparatus are due to the following:

- the presence of a long (more than 1 meter) sampler for sampling gas from the patient’s airways and transferring it to a transducer located in the apparatus body, which reduces the measurement accuracy when registering the fine structure of the capnogram, because distortions may occur due to turbulence of the gas mixture as it passes through the sampler;

- the lack of a standard interface that ensures the operation of the device in combination with a personal computer running software, significantly reduces the diagnostic ability of the device.

Thus, the disadvantages of the apparatus for conducting capnography, selected as the closest analogue of the claimed technical solution, are insufficient measurement accuracy and insufficient diagnostic capabilities.

The problem solved by the utility model is to increase the accuracy of measurements while expanding the diagnostic capabilities of the device.

The problem is solved in that the volume of the measuring chamber is connected directly to the patient’s airways using the remote transducer, while the remote transducer includes a heater that has a heating element and a temperature sensor connected to a thermal stabilization unit, a heat exchanger, a sleeve, a funnel, and a cover, which have openings through which the measuring chamber is filled, and an ultrasonic transducer for measuring carbon dioxide concentration electrically connected to a measuring unit, which includes an excitation path, a registration path, a thermal stabilization unit, an analog-to-digital converter, a non-volatile memory module for storing registered capnograms, a microprocessor, an indication unit, in addition, the measuring unit can be connected to a personal computer via an interface.

The utility model is illustrated in the drawing. Figure 1 schematically shows the inventive apparatus for capnography. The patient’s air paths using a mouthpiece 1 are connected to the capnograph measuring chamber 2, which houses an ultrasonic transducer for determining the concentration of carbon dioxide 3. In order to prevent condensation of water vapor in the measuring chamber 2, a heater 4 is provided, heated to a temperature of 37 ° С by a heating element 5. To maintain the optimum temperature of heater 4, a temperature sensor 6 is attached to it. Measuring chamber 2 with a converter 3, heater 4, heating element 5 and thermo a sensor 6 is mounted in the housing of the remote transducer 7. In order to create a laminar air flow, a special sleeve 8 is fixed to the front of the remote transducer 7, which has openings for the passage of air 9, inside which a funnel 10 is placed, which ensures full filling of the measuring chamber with an air sample at small values ventilation. A heat exchanger 11, made of a heat-conducting material (aluminum) and having collimation holes 12, providing optimal filling of the measuring chamber 2 with an air sample, is inserted into the central part of the remote converter 7. An easily removable lid 13 is fastened to the rear part of the remote converter 7, having ends 14 for air passage from the end. The cross sections of the holes 9 of the sleeve, funnel 10, heat exchanger 12, cover 14 are selected so that

provide high accuracy measurements over a wide range of air flow rates. In order to control the operation of the heating element 5, depending on the temperature of the heater 4 measured by the temperature sensor 6, a thermal stabilization unit 15 is provided. To ensure the operation of the ultrasonic transducer 3, the latter is connected to the excitation path 16 (for generating ultrasonic radiation) and to the registration path 17 (for receiving ultrasonic radiation). For the purpose of reflection and subsequent registration of the ultrasonic wave, the measuring chamber 2 has a reflector 18. Using an electric communication channel, the signals from the ultrasonic transducer 3 enter the measuring unit 19, which contains an analog-to-digital converter 20, a non-volatile memory module for storing registered capnograms 21, the microprocessor 22 and the display unit 23. The measuring unit 19 through the interface 24 can be connected to a personal computer (PC) 25.

The device for capnography can work in two modes: without connecting to a PC (stand-alone mode) and with a PC connection (mode under PC control). In stand-alone operation, the device provides recording in non-volatile memory, storage and removal of capnograms, calculation and indication of CO ₂ concentration, respiratory rate, ratio of inspiration and expiration durations. To operate the device in PC-controlled mode, special software (software) is used. The software is designed to automate capnometry and provides reception and display on the computer monitor of the patient’s external respiration parameters, output of stored capnograms to the monitor, processing and analysis of capnograms, generation of expert estimates and final conclusions on capnograms, and management of patient databases.

Apparatus for capnography works as follows. The patient is sitting in a comfortable position for him. Using the mouthpiece 1, the patient’s airways are connected to the measuring chamber 2. In stand-alone mode, the measuring unit 19 is turned on and the capnogram is registered in non-volatile memory 21. When implementing the capnography mode under the control of a PC, the measuring unit 19 is connected to the PC 25. Next, registration is performed the patient in the database with the subsequent recording of the capnogram in real time. Also in capnography mode

running PC, you can enter capnograms from the non-volatile memory of the capnograph or from the database to the PC. PC capnography software allows you to perform various diagnostic modes (mass examination mode or special examination mode with stress tests), which significantly expands the diagnostic capabilities of the device. The mass examination mode allows rapid diagnostics of external respiration disorders for a short time in a significant number of patients (during dispensary examinations, professional selection, etc.). The special examination mode provides in-depth diagnosis of disorders of the function of external respiration in specialized departments.

The implementation of the apparatus for capnography in the form of a direct connection of the measuring chamber with the airways of the patient eliminates the turbulence of the gas flow and mixing of the gas mixture, which increases the accuracy of measurements, and the ability to work in conjunction with a personal computer under the control of software provides an extension of the diagnostic capabilities of the apparatus.

LITERATURE

1. "Normocap-200-oxy". Service Manual. - Datex. - 1990. - P.134 (prototype)

Claims (3)

1. Apparatus for capnography, comprising a converter for measuring carbon dioxide concentration and a measuring unit, consisting of an analog-to-digital converter and an indication system, characterized in that the volume of the measuring chamber is connected directly to the patient’s airways using the remote converter, and the converter includes a heater that has a heating element and a temperature sensor connected to the thermal stabilization unit, a heat exchanger, a sleeve, a funnel and a cover, openings through which the measuring chamber is filled, and the ultrasonic transducer for measuring carbon dioxide concentration is electrically connected to the measuring unit, which further includes an excitation path, a registration path, a thermal stabilization unit, a non-volatile memory module for storing registered capnograms, a microprocessor, in addition, a measuring one the unit through the interface can be connected to a personal computer. 2. The device according to claim 1, characterized in that it can operate in two modes: without connecting to a personal computer (stand-alone mode), which provides mobility and portability of the device, and with connecting a personal computer (mode controlled by a personal computer), which provides an extension of the diagnostic capabilities of the apparatus. 3. The apparatus according to claim 1, characterized in that the cross-sections of the holes of the sleeve, funnel, heat exchanger, cover are selected in such a way as to ensure high accuracy of measurements over a wide range of air flow velocities.