JPS61203947A - On-line monitoring apparatus for living body - 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 Application of the Invention] The present invention relates to an online monitoring device for a living body, and in particular, a monitoring device suitable for repeatedly collecting blood from a living body and measuring the blood component concentration using an electrochemical sensor. Regarding.

[Background of the invention]

・Artificial organs play an important role as auxiliary devices during patient surgeries. One such artificial organ is an artificial liver, and research is underway to develop a liver function support device that uses the artificial liver to detoxify and metabolize harmful substances in a patient's blood. This liver function support device has an online monitoring device for monitoring the patient's condition every moment.

The monitoring device has a flow-type analyzer equipped with a plurality of electrodes in the sample flow path, and samples blood by diverting it from the artificial liver blood introduction flow path toward the analyzer.

A conventional monitoring device is, for example, disclosed in Japanese Patent Application Laid-open No. 58-102.
As shown in Japanese Patent No. 164, a double inner tube cannula is used to intermittently collect blood and continuously analyze it without interrupting the flow of the diluent. Although this method can reduce the amount of blood to be collected compared to previous methods, the amount of blood collected cannot be reduced sufficiently because the blood diffuses into the diluent.

[Purpose of the invention]

An object of the present invention is to provide a biological online monitoring device that can prevent blood from spreading during sampling and reduce the amount of blood to be collected.

[Summary of the invention]

In the present invention, three inner tubes are opened in the sampling probe, and each inner tube is connected to one of a liquid suction means, a reference solution supply means, or a bubble supply means to the measurement cell, and blood is intermittently supplied to the measurement cell. When blood is drawn manually, an air bubble is inserted between the blood and the reference solution. The blood flows within the channel toward the measurement cell in a state where it is fractionated by air bubbles.

[Embodiments of the invention]

An embodiment of the present invention will be described using FIG. 1 and FIG. 2. FIG. 1 is a schematic diagram of the overall configuration of the embodiment, and FIG. 2 is a sectional view of its sampling probe.

First, in FIG. 2, the sampling probe 7 includes an outer tube 1 shaped like a syringe needle, a first inner tube 2 for inflowing a reference solution, a second inner tube 3 for blood aspiration, and a third inner tube 3 for air bubble inflow. It is composed of an inner tube 4 and a holder 5 that holds the above three types of inner tubes.The tip of the outer tube 1 is an opening 51 having an inclination.
Blood flows in from this open end. The position of the tip 41 of the inner tube 4 of the bubble inflow tube 3 is preferably the same as the tip 31 of the second inner tube 3 for blood suction, or closer to the open end of the outer tube 1. On the other hand, it is sufficient for the tip 21 of the inner tube 2 of the reference solution inflow cylinder 1 to protrude slightly from the holder 5. This online sampling probe has 3
It has a simple structure in which the purpose can be achieved by simply fitting the holder 5 holding the inner tube of seeds into the outer tube 1.

An online blood monitor is implemented in which an online sampling probe 7 is introduced into an extracorporeal circulation system 6 equipped with an artificial liver, and blood gases, electrolytes, blood sugar, urea nitrogen, etc. in the blood are measured with an electrochemical sensor placed in a measurement cell 10. A flow path diagram when configured is shown in FIG. The inner pipe 2 of the reference solution inflow cylinder 1 shown in FIG. 2 is connected to a pipe 16 that supplies the reference solution 15.
The second inner tube 3 for blood suction transfers the aspirated blood to the measuring cell 10.
The inner pipe 4 of the bubble inflow cylinder 3 is connected to the pipe 17 leading to the air bubbles, and the inner pipe 4 of the bubble inflow cylinder 3 is connected to the pipe 18 that introduces the bubbles. Pump 8, 11
, 14 are controlled by a microcomputer 20.

Normally, a reference solution 15 is supplied to the sampling probe 7 through a pipe 16 by a liquid feeding pump 14, and the outer tube 1 is filled up to the open end with the reference solution.

Here, as the standard solution, heparin-containing physiological saline or a standard solution prepared to have a normal biological σ value composition is used. On the other hand, the suction pump 11 can aspirate the reference solution in the probe 7 at approximately the same flow rate as the pump 14, and the liquid is discharged through the measurement cell 10 into the waste liquid container 13. Therefore,
The reference liquid 15 is hardly discharged into the extracorporeal circulation system 6,
It will be discharged through the tip of the sampling probe 7, the measurement cell 10, etc.

When calibrating the measurement cell 10, the liquid pump 14 is stopped;
The solution introduced into the measurement cell 10 is switched by the switching valve 9, and the standard solution 12 is sucked in by the suction pump 11 to perform calibration.

During blood suction, the pumps 11 and 14 are stopped, and the air supply pump 8 is operated for a certain period of time to introduce air bubbles from the inner tube 4 to the outer tube 1 through the pipe 18. However, the air bubbles do not exit the sampling probe. If the amount of air bubbles introduced at this time is smaller than the volume from the tip 41 of the inner tube 4 to the open end 51 of the outer tube 1, air bubbles can be prevented from entering the extracorporeal circulation system 6. When a certain amount of air bubbles are introduced, the air supply pump 8 is stopped, and the suction pump 11 is activated to suck out the previously introduced certain amount of air bubbles and a certain amount of blood from the second inner tube 3, and the reference The solution and air are separated and guided to the measurement cell 10 through the pipe 17.

When a certain amount of blood has been suctioned, the pump 11 is stopped, and then the pump 8 is activated to introduce a certain amount of air bubbles into the outer tube 1 again. After the air bubbles introduced at this time are suctioned by the pump 11, the pump 14 is immediately operated to guide the reference solution 15 through the tip of the sampling probe 7, from the inner tube 3 through the piping 17, and into the measurement cell 10.

When the pump is controlled as described above, a certain amount of blood aspirated becomes a band with air bubbles at both ends, that is, an array of reference solution - air bubbles - one blood - one reference solution - and passes through the measurement cell 10. The biochemical components in the blood are measured using ion electrodes, enzyme electrodes, etc. The tip of the sampling probe 7 is always washed with the reference solution 15, which also serves as a cleaning solution, except for the scheduled time on the blood side.
In other words, etc. will not occur. This sampling probe is 1
It can be installed not only in an extracorporeal circulatory system but also directly in a blood vessel.

As described above, by using the measuring instrument 19 composed of the sampling probe 7, the measuring cell 10, etc., blood is sampled intermittently or continuously from the extracorporeal circulatory system or blood vessels, and the biochemical components in the blood can be measured over time. can be monitored.

If the sampling probe of this example is used.

Even in online measurements, blood can be fractionated by air bubbles, and interdiffusion with the reference solution is extremely reduced. Therefore, the amount of blood collected from the extracorporeal circulation system or blood vessels can be reduced, and highly reliable measurement results can be obtained with a small amount of blood.

Effect of Completion According to the present invention, since the reference solution and blood can be separated by air bubbles, the diffusion of blood in the flow path can be reduced, and therefore the amount of blood to be collected for on-line measurement can be reduced.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of the present invention, and FIG. 2 is a diagram showing a cross section of a sampling probe in the embodiment of FIG. DESCRIPTION OF SYMBOLS 1... Outer tube, 2,3.4... Inner tube, 7... Sampling probe, 10... Measurement cell. Patent applicant: Director of the Agency of Industrial Science and Technology Todoroki Tatsume tlfJ Tsume 2 Figure

Claims (1)

[Claims] 1. Equipped with a sampling probe in which an inner tube for suction is disposed inside an outer tube having an opening for blood inflow, and a measurement cell having an electrochemical sensor, the sampling probe is intermittently connected to the measurement cell via a flow path. In a biological online monitoring device that directly introduces blood, an inner tube for introducing a reference solution and an inner tube for introducing bubbles are provided in the sampling probe, and a standard solution is intermittently introduced into the sampling probe through the inner tube for introducing the reference solution. 1. An online monitoring device for a biological body, comprising means for intermittently supplying air bubbles into the sampling probe through the inner tube for introducing air bubbles.