JPS62155834A - Blood gas continuous monitor apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a blood gas continuous measuring device for ascertaining the condition of a patient undergoing cardiac surgery, particularly during extracorporeal circulation including an artificial lung.

[Conventional technology]

The current continuous blood measurements are H and F.

Measurement of Ni+ concentration in extracorporeal circulation by Osswald et al.
CLINICAL CHEMISTRY, 25-1.
39/43 (1979), Totani et al. during extracorporeal circulation, p.
Measurement of H...Journal of the Japan Clinical Laboratory Automation Research Society, separate volume,
5-3.14/19 (1980), Measurement of pH, p C02 by Matsuo et al. using 15FET... IEICE Medical Electronics and Bioengineering Laboratory MBM, 79-81 (1981),
Continuous measurement of glucose in portable artificial pancreatic islets by Shichiri et al....Artificial Organs, 9.1094 (1980), Gonda et al.'s Glucose, pO2, I) Co2, Na, p
Multi-item continuous blood monitoring device using H1K+...
・Artificial organs vol. 1, 10.6 (1981), etc.

[Problem that the invention seeks to solve]

In cardiac surgery, especially when extracorporeal circulation including an oxygenator is used, blood gas composition changes quickly and fluctuates widely, so measurement of these is essential. Currently, blood is sampled from time to time.
Measurements are being made using a blood gas analyzer, but it cannot be said to be sufficient.

A system that continuously and simultaneously measures the three items required during extracorporeal circulation, pH, pcO2, and pO2, has not yet been put to practical use. In addition, with devices in which the sensor is placed inside the body, blood clots may form on the sensor surface, resulting in inadequate measurement stability and accuracy (the sensor also deteriorates significantly, and the sensor is miniaturized, resulting in poor durability and low running costs). There are such drawbacks.

In consideration of the above points, the purpose of the present invention is to improve the safety of surgery by promoting prompt changes in biological information, and to save the time required for measurement by automating the device. The present invention aims to provide a blood gas continuous monitoring device constructed as described above.

[Means for solving problems]

In a continuous blood gas measurement device that continuously sucks blood from an extracorporeal circulation circuit and measures ions and dissolved gases in the blood using an electrochemical sensor, calibration liquid, calibration gas, cleaning liquid, saline, air, etc. A solenoid valve circuit consisting of a plurality of solenoid valves used for switching the flow paths of the fluid and blood sample is connected to an outlet of the solenoid valve circuit, and the flow path of the fluid and blood sample is selectively switched, and the fluid is transferred to the sensor. a rotary switching valve composed of multiple pieces for sending the data to the sensor, a constant temperature bath that houses the pcO□, pO2, and pH sensors and bubbler members and keeps the measurement atmosphere at a constant temperature, and arithmetic processing and sequencing of the measurement data from the sensors. The rotary switching valve has a bearing member in the central part of the plane, a plurality of flow channels arranged concentrically around the outer circumference of the bearing member, and a leakage prevention system in the flow channels. The stator member has a sealing member embedded therein, a flow path corresponding to the opening of the flow path of the stator member, and a flow path for forming a conduction path, and a mechanism that rotates by the driving force of a motor or the like. The combination of rotation of the rotor members selectively forms channels in five states: cleaning, preparation, calibration, measurement, and stop. The preparation state speeds up the stabilization of the initial characteristics of the pO2 sensor, the calibration state allows the blood to flow into the bypass path and stagnates the blood sample, and the measurement state allows the blood sample and saline to join together at the waste end. coagulation of blood at the waste end;
Preventing contamination of the flow path, stop state is I) Preventing CO2 and pO2 sensor membranes from drying, concentrating the electrolyte, maintaining pH sensor activity, preventing sensor deterioration and contamination of the flow path, and suspending blood collection. The structure is such that online measurement of ions, pH 1, and dissolved gases p C02 and p 02 in blood can be performed continuously without any thrombus forming in the flow path.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a block diagram of a system according to the present invention. 1
2 is a blood sample introduction part, and 2 is a rotary switching valve, which has stator members 2S-1, 2S-2 and 2S-6 and rotor members 2R-1, 2R-2 and 2R-6, each having a flow path inside. and the stator members 2S-1, 2S-2 and 2S-6 include inflow passages 2a, 2b, 2c and 2d and outflow passages 2A, 2B, 2C and 2D, and the rotor members 2R-1 to 2R The combination of -6 rotations forms a flow path with five states: cleaning, preparation, calibration, measurement, and stop. (Details will be explained later). 6 is an air-type thermostat;
The measurement room is controlled at 37±0.1°C to maintain measurement accuracy. 4.5 and 6 are sensors, and 7 is a bubbler member, which are arranged in the thermostatic chamber 6 and used to humidify the standard gas 8.9 for sensor calibration.

Note that the sensor 4 used in this example has a carbon dioxide partial pressure pCO
2. Sensor 5 was set to oxygen partial pressure p02, and sensor 6 was set to hydrogen ion concentration pH. A pump 10 is used for infusion, and is disposed downstream to introduce the blood sample 1, washing liquid 11, saline 12, and calibration liquid 16 and 14 by suction. 15 is a manifold, and 16 is a waste liquid bottle. 17 is a solenoid valve circuit, which connects the cleaning liquid 11, saline solution 12, and calibration liquid 13.14.
, the standard gas 8.9 and the atmosphere 18 are switched. Reference numeral 19 denotes a solenoid valve, which is disposed in a part of the flow path 20 between the sensor 5 and the infusion pump 10. During the calibration of the sensor 4.5, the solenoid valve is opened and used to discharge the calibration gas. 21 is constant temperature bath 6
The temperature control circuit controls the temperature of the constant temperature bath 6 at 37±0.1°C.

22 is a preamplifier circuit for the sensors 4.5 and 6;
6 is an analog signal processing circuit. Reference numeral 24 denotes a control circuit for the rotary switching valve and electromagnetic valve circuit, which is used for opening/closing operations of each electromagnetic valve in the electromagnetic valve circuit and rotation control of the rotary switching valve 2 according to instructions from a microcomputer 250. 26 is a printer, and the analog signal processing circuit 26
Measurement values, sample numbers, times, etc. processed by the A-D converter and microcomputer 25 are printed out at regular intervals. 27 is an analog terminal,
Connect to an external recorder (not shown) to record continuous changes in measured values. 28 is 1) CO2, po2. This is a digital display device for measuring pH values.

29 is a display device for displaying measurement intervals, temperature, current time, etc., and 60 is an operation panel.

FIGS. 2(a) to 2(e) are explanatory diagrams of the state of the flow path in the rotary switching valve of the present invention.

FIG. 2(a) shows the cleaning state. The cleaning path 2A, the sensor path 2C, and the sensor path 2D are connected to the inflow path 2a, and the bypass path 2B is connected to the inflow path 2b, so that fluids such as cleaning liquid, saline, and air flow into each of the flow paths 2a and 2b. , the cleaning path 2A, bypass path 2B, sensor path 2C12D, and sensor 4.5.6 are cleaned. Air is used, for example, to alternately flow cleaning liquid and air to improve the cleaning effect.

FIG. 2(b) shows a prepared state, in which only the rotor member 2R-2 in FIG. 2(a) is rotated by 180 degrees. The cleaning path 2A and the sensor path 2D are in communication with the inflow path 2a, and the sensor path 2
C is electrically connected to the inflow path 2c, and a calibration gas is caused to flow through the inflow path 2c, thereby speeding up the stabilization of the initial characteristics of the pO2 sensor. At this time, the cleaning path 2A, the sensor path 2D, and the bypass path 2B are filled with fluid such as saline.

FIG. 2(C) shows a calibration state in which only the rotor member 2R-3 in FIG. 2(b) is rotated by 180°. Each outflow path of the cleaning path 2A, bypass path 2B, sensor path 2C, and sensor path 2D becomes an independent flow path, and during calibration, the sensor path 2
p C02 and p02 sensor calibration is performed by sensors 4 and 5 by flowing humidified calibration gas through c.

The calibration was performed using the two-point method: pCO2, pO2 is 39 and 72 mH, 9% p02 is O and 85.6 imH,! i'. A calibration liquid was allowed to flow into the sensor path 2D from the inflow path, and pH calibration was performed for the sensor 6: (Thus, pH calibration was performed. Calibration was performed using a two-point method, and p I-I was set to 7.0 and 7.6.

When calibrating the sensors 4.5 and 6 before measurement, cleaning liquid, air, and saline are introduced into the inflow path 2b to clean the inside of the rotary switching valve and the flow path.

If the sensors 4.5 and 6 are to be calibrated during the measurement, the blood sample flows out through the bypass path 2B of the rotary switching valve.

FIG. 2(d) shows the measurement state, and the rotor members 2R-1, 2R-2 and 2R-6 of FIG. 2(C) are each 18
It is rotated by 0°.

The blood sample flows into the inflow path 2b, passes through the flow path within the rotary switching valve 2, and flows out into the sensor path 2C12D. Sensors 4 and 5 connected to the senna path 2C, sensor path 2
p C02, respectively, by the sensor 6 connected to D.
Measurements of p 02 and pH are taken.

The cleaning path 2A and the bypass path 2B are in communication with the inflow path 2a, and saline and air are flowed through the inflow path 2a at regular intervals to clean and activate the flow path, and as described above, the blood sample is and the saline solution at the waste liquid end at the manifold member 10 to prevent blood coagulation and contamination of the flow path.

FIG. 2(e) shows a stopped state, in which the rotor members 2R-1 and 2R-6 of FIG. 2(d) have been rotated by 180 degrees. The cleaning channels 2A and 2C are in communication with the inflow channel 2a, and the bypass channel 2B and the sensor channel 2D are independent channels. A saline solution is flowed into the inflow channels 2a and 2b, a saline solution is flowed through the washing channel 2A, a bypass channel 2B, a sensor channel 2C, and a sensor 4.5 connected to the sensor channel 2C, and a calibration solution is flowed into the inflow channel 2d. Fill sensor path 2D and sensor 6 with the calibration fluid.

FIG. 3 is a perspective view of the flow path in the rotary switching valve in the measurement state of FIG. 2(d). The rotary switching valve has a plane F1,
K on the concentric circles of F2 and F3, each with a plurality of channels S
11, S21, and 831, and the flow path 811 s S
21, S31 has sealing member pH for leakage prevention, F21
Stator member 2S-1, 28- in which s F31 is embedded
2, 2S-6, and the stator members 2S-1, 2S-2,
It has flow paths R,1, R21, R3, corresponding to the opening of 2S-3, and for forming a conduction path. Note that a seal member P for preventing leakage is provided in the flow path between the stator members.

As described in the measurement state, the blood sample flowing into the inflow path 2b flows through the flow path Sll of the stator 2S-1 → the flow path R11 of the rotor member → the stator member 2S-10 the flow path S21 → the stator member 2S-2 Flow path S22 → rotor member 2R-2
Flow path R21→stator member 2S-20 flows out to sensor path 2C via flow path R22. Said flow path S2. passes through the stator member 2S-2 → the flow path S3+ of the stator member 2S-6 → the flow path R81 of the rotor member 2R-3 → the flow path S3□ of the stator member 2S-6, and then the sensor path 2D leaks to.

FIG. 1 is a sectional view of the rotary switching valve.

28-2 is a stator member, 201 is a bearing member, S21 is a plurality of channels arranged on a concentric circle around the outer circumference of the bearing member 201, and 202 is a seal member, which connects the channel S21 and the rotor member 2R-2. It is used to prevent leakage between the flow paths R21, and the force required for sealing is applied by the spring 206.

The rotation of the rotor member 2R-2 is transmitted by the pin 205 of the shaft 204. The rotor member 2R-2 is configured such that the cap 207 can be attached and detached from the shaft 204, and the passages of the stator member 2S-2 and the rotor member can be inspected and maintained. Reference numeral 208 denotes a rotary positioning plate fixed to the shaft 204, and notches 209 and 210 are provided on the outer periphery at 180° intervals.

The rotary positioning plate 208 is connected by a pin (not shown) to a driving plate 216 fixed to a driving shaft 211 with a pin 212, and is interlocked with a motor 216 and a speed reducer 214. The positioning of the rotation is performed by the roller 215 that comes into contact with the notch 209, 210 of the rotation position plate 208, and the stop position is detected by the microswitch 216, 217.

Figure 5(a) is a front view of the inside of the air thermostatic chamber, Figure 5(b)
is a sectional view taken along line A-A.

601 is a constant temperature chamber body having an open part 601a, 4 is a PC
t2 sensor, 5 is p02 sensor, 6 is pH sensor, 60
2 is a sensor bracket, and 603, 604 and 605 are protrusions provided on the sensor bracket 602. 606
, 307 is a support provided in the main body 301, 308.3
09 is a pivot shaft protruding from the pillar. The sensor bracket 602 is rotatably supported by pivot shafts 608, 609 protruding from the pillars 606, 607 within the range of arrow positions B, , B2.

Reference numeral 310 denotes a lid body having a window portion made up of two transparent plates 610a and 610b. 610C is a handle, 610d is a gasket, and 311 is a hinge. The lid 610 is located at the arrow position C.
1, C2, and is rotatably attached to the main body 310.

Inspection and maintenance of the sensors 4.5 and 6 are performed using the lid body 310.
is performed at position C2 and sensor bracket 302 at position B2, that is, the posture shown by the broken line. - 312 is attached to the main body 601, and a fan 612a
and a heat source consisting of a heater section 612b, and 316c is a heat insulating material. Hot air 312d sent from the heat source 312b
is the outlet 31 of the conduit 613 provided in the main body 601
It flows out from 3a and 313b.

[Effects of the Invention] As is clear from the above explanation, according to the present invention, there is no interruption in measurement due to blood coagulation within the device even after long-term continuous use, and stable measurement and surgical safety are achieved. This has the effect of improving performance and reducing the amount of time required for measurement by automating the device.

[Brief explanation of drawings]

Figure 1 is a block diagram of the system of the present invention, Figure 2 (a)
- (e) are explanatory diagrams of the state of the flow passage in the rotary switching valve, Fig. 3 is a perspective view of the flow passage in the rotary switching valve in the measurement state of Fig. 2 (d), and Fig. 4 is an illustration of the state of the flow passage in the rotary switching valve. FIG. 5(a) is a front view of the interior of the air-type thermostat, and FIG. 5(b) is a sectional view taken along line A-AK. 2...Rotary switching valve, 2A...Washing path, 2B...
...Bypass path, 2C12D...Sensor path, 2S-1
, 2S-2, 2S-3... stator member, 2R-1,
2R-2, 2R-6... Rotor member, 3... Constant temperature chamber, 4... pCO2 sensor, 5... pO2 sensor, 6
...pH sensor, 7...bubbler member, 8.9...
Calibration gas, 11...Cleaning liquid, 12...Saline solution, 13
．． 14... Calibration liquid, 17... Solenoid valve circuit, 25...
・Microcomputer, 201...Bearing member, 21
4...Motor, P, pH, B2B31...Seal member for leakage prevention. Figure 3 Figure 4 201 Axis length cut 214 -E:-9 Figure 5 (Q)

Claims (6)

[Claims] (1) In a blood gas continuous measurement device that continuously sucks blood from an extracorporeal circulation circuit and measures ions and dissolved gases in the blood using an electrochemical sensor, a calibration solution, calibration gas, cleaning solution, saline solution, and A solenoid valve circuit consisting of a plurality of solenoid valves used for switching the flow path of air, etc. is connected to an outlet of the solenoid valve circuit, and the flow path of the fluid and blood sample is selectively switched. A rotary switching valve consisting of multiple pieces to send pCO_2 and pO to the sensor.
_2, a pH sensor and a bubbler member, and a constant temperature bath that keeps the measurement atmosphere at a constant temperature; and a microcomputer that can perform arithmetic processing and sequence management of measurement data from the sensor; A bearing member in the center of the bearing member, a plurality of flow channels arranged concentrically around the outer periphery of the bearing member, a stator member in which a leak-preventing seal member is embedded in the flow channels, and an opening in the flow channel of the stator member. It consists of a rotor member that has a flow path for forming a conduction path and is equipped with a mechanism that rotates by the driving force of a motor or the like. By selectively forming a flow path in five states: preparation, calibration, measurement, and stop, online measurement of ion pH and dissolved gases pCO_2 and pO_2 in blood can be performed without thrombus forming in the flow path or interrupting blood collection. A continuous blood gas monitoring device characterized by continuous measurement. (2) The rotary switching valve composed of multiple valves is
A, bypass path 2B, sensor path 2C and sensor path 2D
The cleaning state is the cleaning path 2A and the sensor path 2C.
The sensor path 2D is electrically conductive, and only the bypass path is formed as an independent flow path, and fluids such as cleaning liquid, saline, and air are allowed to flow through all the output paths, thereby making it possible to clean all of the above-mentioned flow paths. A continuous blood gas monitoring device according to claim 1. (3) In the preparation state, the cleaning path 2A and the sensor path 2D are electrically connected, the bypass path 2B and the sensor path 2C are independent flow paths, and the cleaning path 2
A, the bypass path 2B and the sensor path 2D are configured to flow a saline solution and a calibration gas to the sensor path 2C to speed up the stabilization of the initial characteristics of the pO_2 sensor. 2. The blood gas continuous monitoring device according to item 2. (4) In the calibration state, the cleaning path 2A, bypass path 2B, sensor path 2C, and sensor path 2D are independent flow paths, and the cleaning path 2A is a cleaning solution, saline solution, and air, and the bypass path 2B is a cleaning solution, saline solution, and air. and a blood sample, a calibration gas in the sensor path 2C during calibration, a calibration liquid in the sensor path 2D, a cleaning liquid, saline, air, etc. in the sensor path 2C and sensor path 2D before and after calibration, and the cleaning path 2A and bypass path 2B.
The blood gas continuous monitoring device according to claim 1 or 2, characterized in that the blood gas continuous monitoring device is configured to eliminate stagnation of a blood sample in the blood gas. (5) The measurement state is that the cleaning path 2A and the bypass path 2B, the sensor path 2C and the sensor path 2D are in conduction, saline and air are flowing in the cleaning path 2A and the bypass path 2B, and blood is flowing in the sensor path 2C and the sensor path 2D. Claim 1 or 2 is characterized in that the blood sample and saline are combined at the waste liquid end to prevent blood coagulation and contamination of the flow path at the waste liquid end. Blood gas continuous monitoring device. (6) In the stopped state, the cleaning path 2A and the sensor path 2C are electrically connected, the bypass path 2B and the sensor path 2D are each formed as independent flow paths, and the cleaning path 2A, the bypass path 2B, and the sensor path 2C are formed as independent flow paths.
Fill the sensor path 2D with saline solution and the pH calibration solution to adjust the pCO
_2. Claim 1 characterized in that the pO_2 sensor membrane is dried, the electrolyte solution is prevented from concentrating, the pH sensor is maintained in activity, and the sensor is prevented from deteriorating and the flow path is prevented from being contaminated. Or the blood gas continuous monitoring device described in paragraph 2.