JPH03968Y2 - - Google Patents

Description

[Detailed description of the invention] Background of the invention (technical field) The present invention relates to a liquid sample collection device that enables medically safe collection of liquid samples such as blood from a liquid flow path such as an extracorporeal circulation circuit. It is something.

(Prior Art and its Problems) Conventionally, when collecting test sample blood for measuring various data from an extracorporeal circulation blood circuit, the following method has been adopted.

(1) In dialysis circuits (artificial kidneys), the usual method is to insert a needle into a rubber mixed injection port provided on the circuit and aspirate with a syringe.

(2) In heart-lung bypass circuits, the pressure inside the circuit is often high, so a rubber mixed injection port like the one mentioned above is not used. Usually, a three-way stopcock is installed in the sample collection section, and a blood sample is collected by switching the three-way stopcock. Another reason for not using a rubber mixing spout is that it requires more collection than an artificial kidney. Blood gas components, O ₂ , CO ₂
Gas concentration, ions such as K ⁺ , Na ⁺ , Cl ^- , CA ⁺⁺ , etc.
Since protein concentration, hematocrit, etc. are measured frequently, there are concerns about the durability of the rubber. Furthermore, when using a three-way stopcock, there is a high risk that medical problems may occur due to incorrect operation. In addition, a common drawback of (1) and (2) above is that the syringe must be attached directly to the sampling site, and for example, in cases where the circuit performs drop blood removal, the person collecting the blood may be placed on the floor. There were inconveniences such as having to bend down to perform collection operations.

(3) As a method to improve the drawbacks of (1) and (2) above, a method has been devised in which the sample is pulled out from the sample collection site to an easily accessible location using a thin tube to improve operability. This will be explained in detail later in the drawings.

However, a common problem with (1), (2), and (3) above is that there is a risk of injecting air into the extracorporeal circulation line due to an operational error. In particular, the operation of the three-way stopcocks in (2) and (3) is complicated and extremely dangerous for inexperienced people. There is also the risk that high pressure arterial blood may protrude from the sampling line due to a similar mistake.

Therefore, the inventor of the present invention provides a liquid sample collection device such as blood that is easy to operate and that does not pose the risk of injecting air into the circuit in a liquid flow path such as an extracorporeal circulation blood circuit, particularly in an artificial heart-lung circuit. We have filed a patent application (Japanese Patent Application No. 136154/1982) for the medical sample liquid collection device that is designed to select one specific type of liquid to collect when there are two or more types of liquid to be collected. A flow direction control means for flowing liquid in a fixed direction, including two check valves arranged in series in a liquid flow path, and a liquid sampling device provided in a flow path between the check valves. and a switching means provided at a liquid inlet of the liquid sampling mechanism to selectively communicate with a plurality of liquid channels, the switching means being provided at a liquid inlet of the liquid sampling mechanism and selectively communicating with a plurality of liquid channels, The fluid is configured to be prevented from migrating to the liquid inlet. In order to further improve the above-mentioned device, the inventor of the present invention aims to improve the safety during use, that is, when tensile stress is applied to the blood circuit due to the operator's actions, each connecting member will separate, blood will flow out, and the equipment will be contaminated. In order to prevent this and eliminate the risk of blood in the flow path flowing out due to loosening of the connection between the liquid sampling mechanism and the switching means when fluid pressure is applied to the check valve, we have also improved operability. This was considered from the point of view of improvement.

Purpose of the invention As mentioned above, the purpose of the invention is to prevent disconnection of each connecting member, detachment of the switching means from the liquid sampling device,
The object of the present invention is to provide a medical fluid collection device that eliminates the risk of blood flowing out of a flow path and has improved operability.

A liquid sampling device that achieves the above object includes a liquid sampling section provided between the inlet and the outlet of a channel having a liquid inlet and a liquid outlet, and a liquid sampling section provided in the channel between the liquid sampling section and the inlet. A first check valve is provided in the flow path between the liquid sampling portion and the outlet, and is provided with a first check valve that opens only in the direction of the liquid sampling portion and does not open due to the liquid pressure of the liquid, but opens due to the suction force applied to the liquid sampling portion. a liquid sampling mechanism provided with a second check valve that opens only in the direction of the outflow port and by a pressing force applied to the liquid sampling section; a mounting section attached to the liquid inflow port; and one or more fluid flow path mounting ports. and a switching means having a switching knob for selectively communicating between the mounting port and the mounting portion, and further comprising: a switching means having a switching knob for selectively communicating between the mounting port and the mounting portion; The liquid collecting part and the liquid outlet, as well as a box body that protrudes and houses the fluid flow path attachment port and the switching pot of the switching means.

More preferably, the pressure for opening the flow path in the certain direction of the check valve is at least 500 mm.
Hg or higher.

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, a liquid sample collection device according to the present invention will be described in detail with reference to the accompanying drawings. Although this description will be made using an artificial heart-lung circuit as a representative example, the present invention is not limited to this.

FIG. 1 is a perspective view of an example of an artificial heart-lung circuit.
Blood removed from the patient's vena cava is in blood removal line 1.
After that, the blood from the surgical field passes from the suction line 2 and pump 3 to the intracardial blood reservoir 4 and line 5.
The blood enters the venous reservoir 7 housed in the capacity regulating means 6 and is further sent to the oxygenator 9 with a heat exchanger by the pump 8, where the blood is oxygenated and flows through the blood supply line 1.
0 and then returned to the patient's body. 11 is a circulation line used as necessary.

In the artificial heart-lung circuit as illustrated in FIG. In order to confirm whether or not the blood supply is appropriate, it is necessary to sample blood from the blood removal line 1 and/or the blood supply line 10 for testing. As mentioned above, the conventional methods (1) and (2) mentioned at the beginning of this specification have too many problems in sampling, so the method mentioned in (3) was developed. ing.

This sampling method will be briefly explained with reference to FIG.

The blood removal line (abbreviated as V line) and the blood feeding line (abbreviated as A line) each have a first line.
As shown at 12 and 13 in the figure, thin sampling tubes 21 and 22 are connected, and three three-way stopcocks 23, 24 and 25 on the right side, center and left side are arranged in parallel in the center. Each three-way stopcock is provided with a sampling blood collection port.

Initially, the left and right three-way stopcocks 23, 25 are in an off state (not connected to the A or V line), as shown in FIG. 2d. Now, when trying to collect arterial blood from the A line, attach a dummy syringe to the three-way stopcock 24 in the center, and insert the dummy syringe into the three-way stopcock 23 on the right side.
is turned on (connected to the A line) (see Figure 2a). As a result, the stale blood remaining in the sampling tube 22 on the A-line side is sucked out by the dummy syringe. Next, the central three-way stopcock 24 is turned off, and a syringe for collecting test blood is attached to the right three-way stopcock 23 to collect fresh blood (see Figure 2b). After completing the collection, turn off the three-way stopcock on the right side, turn on the three-way stopcock 25 on the left side, and return the blood in the dummy syringe to the V line via line 21 (second
(see figure c). Finally, all three-way stopcocks are turned off to complete the sampling. In the case of blood sampling from the V line, the procedure is the same as above except that the blood sampled into the dummy syringe is returned to the V line.

This method has an advantage over methods (1) and (2) mentioned at the beginning of the specification in that all operations can be performed at hand, but as mentioned above, the operation of the three-way stopcock is complicated. It requires training, and if you turn on stopcock 23 instead of 25 in the procedure shown in Figure 2C, air will be pumped into the A line (arterial side), which can lead to serious complications such as occlusion of cerebral capillary blood. There is a danger that this may occur.

As explained above, in order to collect fresh sampling blood, the blood in the sampling line connected to the V line and/or A line must be removed beforehand, and the removed blood should not be transferred to the A line. , it must be returned to the V-line side, which has a defoaming function. If this operation is performed incorrectly, it is extremely dangerous as it can cause life-threatening problems, but this problem has not been solved with the device shown in Figure 2.
The operation is complicated and erroneous operations are likely to occur.

Therefore, with the present invention, the risk of air intrusion can be completely avoided in any case, especially in circuits where air should be prevented from entering, such as an artificial heart-lung circuit, and moreover, it does not involve the complicated operation of a three-way stopcock. The present invention aims to provide a safe and simple sampling device, which will be described in detail below.

FIG. 3 shows an apparatus of the present invention for collecting venous or arterial blood in a heart-lung machine as shown in FIG. The present device comprises a liquid sampling mechanism 35, a switching means 39, and a box body 70 that houses the device to which the liquid sampling mechanism 35 and switching means 39 are attached. Then, the liquid collection mechanism 35 is
It has a blood inlet 34 and a blood outlet 36.
Furthermore, two check valves are provided inside to allow only one-way flow.

A syringe 37 is inserted between the two check valves.
It has a blood sampling section 38 to which a suitable blood sampling device such as a blood sampling device can be attached. Next, two check valves will be explained. First, the first check valve 32 located between the blood sampling section 38 and the blood inlet opens only so that fluid flows only in the direction of the blood sampling section 38 . However, this check valve 32 is not opened only by the fluid pressure of the blood flow applied to the check valve, but is opened by the suction force generated in the blood sampling section 38 when the above-mentioned syringe 37 is aspirated. be. Next, the blood sampling section 38
The second check valve 33 provided between the syringe 37 and the blood outflow port 36 opens so that blood flows only in the direction of the blood outflow port. It opens due to the generated pressing force. A tube 62 is attached to the blood outflow port 36, and the tube 62 is connected to the V-line side or the intracardiac blood reservoir (intracardial blood reservoir), which has a defoaming function that does not cause problems even when air is mixed in. (shown as 4 in Figure 1). As mentioned above, connecting the tube 62 to the V line instead of the A line prevents air from being sent to the A line side by pumping (inserting and pulling) the syringe 37, as will be explained later in the function section. This is to ensure that.

Next, the switching means 39 will be explained. The switching means 39 is connected to the blood inlet 34 of the liquid collection mechanism 35 described above.
For example, a three-way stopcock. Specifically, the switching means 39 has a switching pot 48, an attachment part 42 for attachment to the blood inlet 34, and further has two fluid flow path attachment ports 44, 46. A tube 60 is attached to the fluid flow path attachment port 46, and this tube 60 is connected to the A line. In addition, a tube 64 is provided at the fluid flow path installation port 44.
is attached, and this tube 64 is connected to the V line. By operating the switching knob 48, the fluid flow path attachment port 46 and the attachment portion 42 can be selectively communicated with each other, and the fluid flow path attachment port 44 and the attachment portion 42 can be selectively communicated with each other. Specifically, when collecting arterial blood, the fluid flow path attachment port 46 communicating with the A line
Switching point 48 so that the and mounting portion 42 communicate with each other.
operate. Further, when collecting venous blood, the fluid flow path attachment port 44 and the attachment portion 42 are communicated with each other. When no arteriovenous blood is collected, the switching knob 48 can be set to the off position. The switching selection means 39 can also be configured to have more connections, if necessary.

In addition, the blood sampling section 38 is preferably structured so that the distal end of the syringe 37 can be easily and securely attached, and the syringe will not come off due to arterial blood pressure, and is usually formed as a tapered fitting surface. Furthermore, it is preferable to include a locking mechanism for preventing detachment. .

Next, the box 70 that houses the device in which the switching means 39 is attached to the liquid sampling mechanism 35 will be explained. The box body 70 consists of a housing 72 and a lid body 74. The casing 72 is a rectangular casing with semicircular chamfers at both ends, and has a recess 76 fixedly housing the bottom of the switching means 39 on the inner bottom surface and a first portion of the liquid sampling mechanism 35.
In order to grip the installed portion of the check valve 32, the protrusion 78 has a notch that substantially matches the shape of the installed portion of the check valve 32. Further, a switching means 3 is provided on the outer peripheral wall of the housing 72.
It has notches 80a, 82a for protruding the fluid flow path attachment ports 44, 46 of 9, and notches 84a, 86a for protruding the blood outlet 36 and blood sampling part 38 of the liquid sampling mechanism 35. The lid body 74 has almost the same shape as the housing 72, has a notch 90 on the top surface for protruding the switching knob 48 of the switching means 39, and has an outer peripheral wall similar to the housing 72 described above. At the top are the fluid flow path attachment ports 44 and 46 of the switching means 39 and the blood outflow port 36 of the liquid sampling mechanism 35.
and a notch 80 for protruding the blood sampling section 38.
b, 82b, 84b, and 86b. Furthermore, it is preferable to provide mechanisms 88a and 88b for engaging the housing 72 and the lid 74. In the above explanation, the blood sampling part etc. can be protruded by providing a notch in both the casing and the lid and combining the two notches, but there is an alternative method in which a notch is provided only in the casing or the lid. may be provided. A switching means 39 is provided in the box body 70 constituted by the above-mentioned housing 72 and lid body 74.
By housing the liquid sampling mechanism 35 with the attached fluid collection mechanism 35, the connection between the blood inlet 34 and the attachment portion 42, which are the attachment portions of both, will not loosen.

Note that the connection to the A or V line in FIG. 3 is made through the connector 40.

As the check valve used in the liquid sample collection device of the present invention, generally known check valves can be used. The check valve 32 on the upstream side is required to prevent blood from leaking even under arterial blood pressure, and has a resistance of 500
It is preferable to have a value of mmHg or more, because it is possible to prevent arterial blood from gushing out even when the syringe 37 is removed.

A preferable check valve for use in the liquid sampling device of the present invention will be described with reference to an enlarged partial cross-sectional view of a liquid sampling mechanism shown in FIG. The check valve 33 includes an inner cylindrical portion 100 that protrudes toward the blood outflow port 36 and has a closed end, a through hole 102 provided on the outer circumferential wall of the inner cylindrical portion, and the above-mentioned through hole on the outer circumferential wall of the inner cylindrical portion 100. A cylindrical valve body 104 is fitted so as to close the valve body 102. An annular rib 106 that locks the valve body is provided at the base end of the inner cylinder portion 100 to prevent the valve body 104 from moving. If the check valve is constructed in this way, it can be made smaller, so the liquid sampling mechanism itself can also be made smaller, and the dead space created inside can also be made smaller. The valve body 104 can be made of a flexible material such as silicone rubber, polyolefin elastomer, polyurethane elastomer, polyamide elastomer, latex rubber, or the like. Preferably it is silicone rubber. It is preferable that the wall thickness is about 0.4 mm and the length is about 6.5 mm.

Further, as the switching selection means, any device may be used as long as it is capable of selecting one of a plurality of inflow ports, but a three-way stopcock commonly used for medical purposes is preferable.

Both the liquid inlet and outlet of the sampling line are connected via connectors to the line through which the liquid to be sampled is flowing. In this case, it is particularly important to ensure that the connector connected to the arterial blood line does not come off even at arterial blood pressure (maximum 500 mmHg).

Specific effects of the invention The method for using the liquid sampling device of the invention is described in the first section.
An example of application to the artificial heart-lung circuit shown in the figure will be explained.

First, in the example of the blood inflow section 34 shown in FIG.
Connect 6 to the V line or intracardiac blood reservoir. In this state, the blood to be collected is collected from the upstream check valve 3.
It has reached position 2.

When collecting blood, the syringe 37 is attached to the blood sampling member attachment part 38, and when the syringe is aspirated,
Blood enters the syringe 37 via the check valve 32 due to the suction pressure. However, this blood
This is not fresh blood that had been retained in 4, and is not suitable for testing. Therefore, this unfresh blood is discharged by the syringe discharge operation. At this time, this blood can flow towards the check valve 32. It passes through the check valve 33 and returns to the V line side, ie, the V line, venous reservoir (VR), or intracardiac blood reservoir (CR), via the blood discharge section 36. The priming volume of the blood inlet 34 of the sampling line 31 is generally 3 to 8 c.c.
Since the syringe used is 2.5cc, it is necessary to pump the syringe 3 to 4 times to collect fresh blood, but even if air is mixed in at this time, the blood containing air will be removed from the blood inlet. It will not flow backwards towards you. Therefore, even when collecting arterial blood, air is never injected into the arterial A line. After several pumps, the required amount of fresh blood is collected into the syringe and the blood collection is completed. Even when blood is to be collected frequently, fresh blood can be collected by simply attaching the syringe 37 to the blood collection member attachment part 38, pumping several times, and then collecting the required amount of blood. .

The connector that connects to the A line is the maximum arterial blood pressure.
Even if it is over 500mmHg, it will not come off and blood will gush out. Furthermore, if the flow path opening pressure of the check valve for arterial blood sampling is set to 500 mmHg or higher, blood will not flow into the syringe except during suction, thus preventing dripping when blood is not being collected.

Specific Effects of the Invention The liquid sampling device of the present invention provides many advantages over conventional ones, as described below.

(1) Regarding the present invention, even when blood is collected from the arterial line, there is no risk of introducing air into the arterial line.

(2) Furthermore, the device of the present invention does not require the complicated operation of a three-way stopcock, unlike conventional devices, and even non-experts can reliably collect test blood without causing any operational errors.

(3) Like the conventional circuit that performs drop blood removal,
This allows safe operation at the pull base without the inconvenience of having to bend down and reach into the back.

(4) Whether there is a single liquid flow path or a plurality of liquid channels to be sampled, the liquid can be sampled by the same extremely simple operation.

(5) In this device, even if arterial pressure builds up in the check valve, the attachment between the fluid collection mechanism and the switching means will not loosen, thereby preventing blood from leaking from the attachment part. Even when the switching means is operated, the attachment portion between the liquid collection mechanism and the switching means does not come off, and therefore blood does not flow out from the attachment portion, allowing blood to be collected safely.

(6) If the flow path opening pressure of the check valve is set to 500 mmHg or higher, blood will not drip from the syringe attachment part when the syringe is not attached, even during arterial blood collection.

(7) Furthermore, in the present invention, two check valves are housed in the liquid sampling mechanism, so the dead space can be reduced.

(8) Furthermore, since the liquid sampling mechanism having the check valve and the switching means are housed in the box, the switching knob of the switching means can be easily rotated.

(8) According to the present device, it is possible to prevent the connecting portion from twisting during use, thereby improving operability.

(9) Furthermore, it is possible to prevent blood from flowing out due to disconnection between the liquid sampling mechanism and the switching means when tensile stress is applied within the circuit due to the operator's actions.

(10) Furthermore, when an unnecessary external force is applied to this device, the influence on the internal mechanism constituting this device can be alleviated and damage can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an example of an artificial heart-lung circuit, Fig. 2 is a diagram for explaining the operating procedure of an example of a conventional blood sampling device, and Fig. 3 shows the device of the present invention with the lid removed. 4 is a diagram showing the housing of the box of the device of the present invention, FIG. 5 is a diagram showing the lid of the box of the present invention, and FIG. 6 is a diagram showing the liquid collection of the device shown in FIG. 3. FIG. 3 is an enlarged partial cross-sectional view of the mechanism. Explanation of the codes, 1...Blood removal line, 2...Suction line, 3, 8...Pump, 4...Intracardial blood reservoir,
5... Line, 6... Capacity regulating means, 7... Venous reservoir, 9... Oxygenator with heat exchanger, 10... Blood supply line, 11... Circulation line, 12, 13...
Sampling line, 21, 21... Sampling line, 23, 24, 25... Three-way stopcock, 31
...Sampling line, 32, 33...Check valve, 34...Blood inlet, 35...Blood sampling mechanism, 36...Blood outlet, 37...Syringe, 3
8...Blood sampling section, 39...Switching means, 40...
connector.

Claims (1)

[Claims for Utility Model Registration] (1) A liquid sampling section is provided between the inlet and the outlet of a channel having a liquid inlet and a liquid outlet, and a liquid sampling section is provided in the channel between the liquid sampling section and the inlet. A first check valve is provided in the flow path between the liquid sampling portion and the outlet, and is provided with a first check valve that opens only in the direction of the liquid sampling portion and does not open due to the liquid pressure of the liquid, but opens due to the suction force applied to the liquid sampling portion. a liquid sampling mechanism provided with a second check valve that opens only in the direction of the outflow port and by a pressing force applied to the liquid sampling section; a mounting section attached to the liquid inflow port; and one or more fluid flow path mounting ports. and a switching means having a switching knob for selectively communicating between the mounting port and the mounting portion, and further comprising: a switching means having a switching knob for selectively communicating between the mounting port and the mounting portion; 1. A liquid sample sampling device comprising a box that houses a liquid sampling section, a liquid outlet, a fluid flow path attachment port of the switching means, and a switching pot in a protruding manner. (2) The liquid sample sampling device according to claim 1, wherein the pressure for opening the flow path in the certain direction of the check valve is at least 500 mmHg or more.