SU1586681A1 - Apparatus for checking ph and concentration of gasses in blood - Google Patents

Abstract

The invention relates to medical technology, namely, to control and diagnostic equipment and can be used in electrochemical analyzers of gas and ionic composition of microbial blood, including devices for the percutaneous control of blood gases. The purpose of the invention is to increase the reliability of measurements by direct heating of the microenvironment. This goal is realized by introducing into the block 1 primary converters of the second (PO2) 3 and third (PCO2) 4 converters, and in the electronic block 6 of the electronic switch 8. In the presented device, by measuring the ohmic resistance of one of the primary converters (third), temperature during thermostating of the blood sample, thereby providing higher accuracy of the emission of PH and concentration of blood gases. 2 Il.

Description

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The invention relates to medical technology, in particular to control and diagnostic equipment, and can be used in electrochemical analyzers of gas and ionic composition of microbial blood, including in devices for the percutaneous control of blood gases.

The aim of the invention is to increase the reliability of measurements by directly heating the microenvironment.

FIG. 1 shows a functional diagram of the device for monitoring the pH and the concentration of blood gases; in fig. 2 - control unit.

I The device contains a unit 1 of primary converters, including three primary converters 2-4, the values ipH, p02 and rs02, respectively, heating element 5, electronic unit 6, consisting of 1 amplifier unit 7, {electronic key 8, analog-digital I a converter (ADC) 9, a temperature control unit 10 for I, a control unit 11, and a reg; rator | 2.

The control unit 11 (CU) can be implemented, for example, in the form of a microprocessor module based on the KP580IK80A microprocessor and consists of a processor (MP) 13, a clock generator- (TG) 14. made on a KR580GF24 chip, a bus driver (SHF) 15 made on: K589IR12 chip, 16-bit system I dark address bus (AS) 16, system controller (CK) 17 running on; chip KR580VK28, system 8-bit data bus (SM) 18 and 6-bit: control bus (UPR) 19, permanent memory (ROM) 20, executed on the chip K573RF5, random access memory (RAM ) 21, performed on KR537RU10 microcircuits, parallel input-output port (Port BB) 22, implemented on KR580BB55 microcircuit, and timer 23 executed on K580IK53 microcircuit. To reset the MP 13 to the initial state and start, the Reset 24 key is provided, and also keyboard 25 input.

The device has three modes of operation: presetting mode, thermostating mode, and measuring mode.

After the device is connected to the power source with the Reset 24 key, the MP 13 is switched to the initial state, after which it embraces all the memory cells of RAM 21, except RT, where the resistance of the third converter 4 is recorded at 37 °, and starts the program recorded in ROM 20, Initially MP 13 outputs to the recorder 12 a question whether the presetting mode will be carried out (it should be carried out after each change of the third converter 4 or periodically every month of operation) and if after that the key 1 of the keyboard 2 is pressed 5, the device will switch to the preset mode, and if the key is 2, then to the thermostating mode.

In the presetting mode, the unit 1 primary transducers (or the third transducer 4) is placed in an environment with a temperature of 37 ± 0, 1 ° C, held for 10-15 minutes for temperature stabilization, and the key 2 of the keyboard 25 is pressed. 22 supplies the control signal to the second output of the CU 11 and starts the timer 23 for a delay of 0.5 s. The signal from the second output of the CU 11 is inverted by the electronic key 8 and connects the power to the third transducer 4 and, respectively, to the second input of the temperature control unit 10. The signal of the timer 23 on the implementation of a delay of 0.5 s MP 13 sends a control signal through the third 5 output of the control unit 11 to the third input of the ADC 9. After receiving the signal, the ADC 9 starts converting the analog signal received at the second input of the ADC 9 into a digital code at the output of the ADC 9. At the end of the conversion via 0, port BB 22 MP 13 reads the digital code corresponding to the resistance of the third converter 4, writes it to the cell RT RAM 21 and provides information to the recorder 12 about the end of the preset tuning mode.

The electrode system of the device is filled with breakdown and by pressing the key 2 is switched to the thermostating mode. In this case, the MP 13 according to the program recorded in the 0 ROM 20 supplies the control signal to the second output of the control unit 11 and the ohmic resistance of the third converter 4 is measured in the same way as the presetting mode, with the difference that 5 the measured value is recorded not in the cell RT, but in the cell HI. Following this, the MP 13 subtracts the contents of RT from the contents of Ri and, if the difference is greater than zero (ie, Ri RT). then this means that the temperature of the block 1 0 is less than the specified one, because with increasing temperature the resistance of the glass decreases. In this case, the MP 13, via the Port BB 22, supplies the control signal through the first input of the control unit 11 to the first input of the unit 10, a control unit of 55 liters of temperature, and through it heating power element 5 is supplied.

The MP 13 according to the program starts the timer 23 with a delay of 1 s and at the end of the delay the operation cycle is repeated until the measured current resistance value

will be less than or equal to that recorded in RT. Then the MP 13 via Port B 22 supplies the first output of the CU 11 to another control signal to the first input of the temperature control unit 10, whereby the heating element 5 is turned off. At the same time, the MP 13 transmits to the recorder 12 information about the completion of heating and transfer walks to the implementation of the measurement mode,

In the measurement mode, the MP 13 according to the program recorded in the ROM 20, supplies the control signal via the second output of the CU 11 to the second input of the switch. By this signal, the third converter of the pC02 4 is connected to the first output of the switch, the signal from it in this case goes to the second input of the amplifier unit 7 and further to the fifth input of the ADC 9.

At the same time, the signals from the first transducer 2 (pH) and the third transducer 3 (pOa) go to the first and third inputs of the amplifier unit 7 and further to the first and fourth inputs of the A / D converters 9, respectively.

By applying a signal to the second output of the BU 11, the MP 13 starts the timer 23 for a delay of 0.1 s. On the signal of timer 23 on the implementation of this delay, MP 13, through port BB 22, sends control signals to the third input of ADC 9, which, in accordance with the program embedded in ROM 20, alternate the fourth, fifth and sixth inputs of ADC 9 to its output . In this case, the analog signal from the corresponding input of the ADC 9 is converted into a digital code in it and the MP 13 is read by the readiness signal and written into the corresponding cell H pH of the RAM 21, and then alternately (as described above) is written into its memory cells H the remaining inputs of the ADC 9.,

After writing the codes of all measured values (for example, pH, p02 and pCOa) into their H memory cells (HpH, Hp02 and HpC02, respectively) RAM 21 MP 13 according to the program, it performs the procedure for determining the drift of the measured values: from the cell. RAM memory 21,

The cycle of analysis of the drifts of all measured values is repeated until the total drift of the SD is equal to zero. If the LED is zero, the measurement cycle ends and the MP 13 puts the device into thermostatic mode. At this time, the blood sample in the transducer unit 1 needs to be changed and the device is repeated as described, starting with the thermostatic mode.

Thus, in the device by measuring the ohmic resistance of one of the primary transducers, the temperature is monitored during the thermostating of the blood sample and primary transducers, so that, in comparison with the known, a higher accuracy of pH measurement and concentration of blood gases is obtained (by 0.5 - 1 %) higher productivity (by 5-10%) is achieved,.

Claims (1)

Apparatus of the Invention A device for controlling pH and concentration of blood gases, containing series-connected primary transducer block, including a heating element and a transducer, an electronic unit comprising a series-connected amplifier block, whose input is connected to the output of the primary transducer, analog-to-digital converter, to the input which is connected to the output of the temperature control unit, and the control unit, the output of which is connected to the input of the temperature control unit, and the recorder, moreover The second output of the temperature control unit is connected to the input of the heating element, characterized in that, in order to increase the measurement accuracy by direct heating of the microenvironment, two converters are inserted into the primary converter unit and an electronic key is inserted into the electronic unit, the first input of which is connected to the third converter input , the second input is with the second output of the control unit, and the outputs are connected first to the second input of the amplifier unit, the second to the second input of the temperature control unit, the outputs are second converter connected to the first and third inputs of amplifier unit, the outputs of which are connected to the three inputs of the analog-to-digital converter, a fourth input coupled to a third output of the control unit. Yuk  Reset PC-8 sh sh AND AND well / 0-1 21 1Ш nineteen sixteen 5l j .2