JPH03205060A - Perfusion pressure detecting device for perfusion pump - Google Patents

Abstract

PURPOSE:To detect the generation of anomaly in a perfusion tube by alternately detecting the expansion of the perfusion tube due to the pressure variation on the liquid feeding side and liquid supply side in the therapeutic liquid as the displacement of a pressure detecting piece attached in the intermediate part of the finger by the acting force resisting the elastic force of the perfusion tube. CONSTITUTION:A pressure detecting piece 1 which is attached by the acting force resisting the elastic force of a perfusion tube 4 is installed in the intermediate part of fingers 2 arranged in plural rows, and the pressure on the liquid feeding side and liquid sending side in the therapeutic liquid is detected alternately. Accordingly, when the liquid feeding side 4b is in closed state by the pressing operation of the finger 2 for the tube 4b on the liquid sending side, the intermediate part 4c of the tube is expanded by the pressure of the supplied liquid, and since the pressure detecting piece 1 is pushed outside, the liquid feeding side pressure is detected by detecting the displacement. Further, when the liquid feeding side 4a is in closed stated by the pressing operation of the finger 2 for the tube 4a on the liquid feeding side, the liquid feeding side pressure is detected by detecting the displacement of the pressure detecting piece 1 which is pushed out by the pressure of the supplied liquid. The result of the detection includes the fall difference of the therapeutic liquid in the tube 4, and the pressure anomaly due to the closure of the tube 4 and the pressure variation due to a variety of causes in the therapeutic liquid can be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an infusion pressure detection device for an infusion pump, particularly a peristaltic type (width motion type) infusion pump.

(Prior art 1) Infusion is a therapeutic procedure in which a predetermined amount of medicinal solution is continuously administered into the patient's body from a hanging medicine bottle or the like through an infusion tube.Peristaltic infusion pumps used for such infusions is a device in which a plurality of pressure contact pieces (hereinafter referred to as fingers) are arranged along the side of the infusion tube, which sequentially press the infusion tube from the liquid supply side to the liquid delivery side.
The chemical liquid can be sent out by sequentially moving the pressing action of each finger from the liquid supply side to the liquid sending side.

[Problems to be Solved by the Invention] By the way, in the peristaltic infusion pump as described above, if the volume of the drug solution is insufficient during infusion or if a blockage occurs in the infusion tube, the administration of the drug solution cannot be continued at a constant amount. There is a problem with this, which can lead to dangerous situations if it is thoroughly investigated.

In order to prevent such a situation, an infusion pump is equipped with a occlusion detection device to detect the occlusion state of the infusion tube, but conventional examples of infusion pumps equipped with this occlusion detection device include: There is one described in Japanese Patent Publication No. 61-55393. In this device, a fixing piece is provided on each of the infusion suction side and the discharge side of the tube attachment part of a peristaltic infusion pump, and a tube is installed on either the suction side or the discharge side at a part opposite to the fixing piece through the tube. A movable piece is provided that compresses the tube on the other side when it is expanded and expanded, and this movable piece detects expansion and compression of the tube on the suction side and discharge side, and when both movable pieces are in a steady position with no inclination, the infusion is started. The device is equipped with an occlusion detection device that detects that normal infusion is not being performed when the slope is tllE in either direction. However, in such a blockage detection device, abnormality in the liquid is detected at two locations: the suction flll and the intake and outlet sides, so there is a difference in elasticity of the tube at each detection location. There is a problem in that the detection characteristics change at each detection site due to differences in changes over time, differences in detection sensitivity at each detection site, etc. Furthermore, abnormalities in the infusion are detected based on the balance between the inclinations of the movable pieces on the suction side and the discharge side, so the infusion pressure is detected in a state where they are offset. ), or there is a problem that the head pressure of the infusion between the infusion pump and the patient site (discharge side) does not appear in the detection results.

Normally, on the liquid supply side of an infusion pump, head pressure acts on the drug solution surface, but when the drug solution becomes insufficient, that pressure disappears. On the liquid delivery side, water head pressure acts on the medicinal liquid level reaching the area to be treated, and positive pressure occurs due to the flow resistance of the patient's area (syringe needle, etc.) to the infusion, but if the infusion tube becomes clogged, the normal value A more pronounced increase in pressure occurs, and if the infusion tubing circuit disconnects from the thinking site tubule and discharges, the pressure becomes more positive than the normal pressure. Such pressure fluctuations during infusion interfere with normal continuous treatment and impede effective treatment and safe infusion.

Therefore, an object of the present invention is to detect the infusion pressure of the infusion pump on the liquid supply side and the liquid sending side individually, and to detect the occurrence of an abnormality in the infusion tube. The purpose is to provide a detection device.

Means for Solving Problem C) The means for solving the above problem will be explained using FIG. 1 corresponding to the embodiment. In a peristaltic infusion pump in which a plurality of fingers 2 are arranged in order to press the infusion tube 40, a pressure sensing piece 1 is provided in the middle of the arrangement of the fingers 2 and is in contact with the infusion tube 40 with an acting force that resists the elasticity. The invention is characterized in that the expansion of the infusion tube 4 due to pressure fluctuations on the liquid supply side and the liquid sending side is alternately detected as the displacement of the pressure detection piece 1.

[Function] In the device configured as described above, a pressure sensing piece 1 is provided in the middle of the plurality of arranged fingers 2 and is in contact with the infusion duplex 4 with an acting force that resists the elasticity. Since the liquid supply side pressure and the liquid sending side pressure are alternately detected, the liquid feeding side tube 4b
When the liquid feeding side 4b of the tube is in a closed state due to the pressing action of the finger 2 against By detecting the displacement of the pressure sensing piece 1, the liquid supply side pressure is detected. or,
When the liquid supply side 4a of the tube is in a closed state due to the pressing operation of the finger 2 against the tube 4a on the liquid supply side, the intermediate portion 4c of the tube expands due to the pressure of the liquid supply, and the pressure detection piece 1 is moved to the outside of the tube 4. Because it is pushed out by
By detecting the displacement of this pressure sensing piece 1, the liquid feeding side pressure is detected.

This detection result includes the head pressure of the infusion in the infusion tube 4, and can detect not only abnormal pressure due to blockage of the infusion tube 4 but also pressure fluctuations due to various factors during infusion.

Then, by comparing the liquid supply side pressure and the liquid sending side pressure described above and taking the difference, it is found that if the displacement of the pressure detection piece is the same, the liquid supply side pressure and the liquid sending side pressure are equal, and the pressure Detection piece 1
For example, if the amount of displacement is greater on the liquid feeding side pressure than on the liquid supplying side, it can be known that an abnormality such as a blockage has occurred on the liquid feeding side of the infusion tube 4.

[Embodiment 1] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing the principle of an infusion pressure detection device provided in a peristaltic infusion pump. As shown in the figure, a bell-squeak type infusion pump unit 8 fixedly held on a main body 7 includes a holding member 5 supported on a substrate (not shown) via a spring 6, and a plurality of holding members 5 arranged facing each other on the holding member 5. An infusion tube 4 made of soft vinyl chloride is inserted between the holding member 5 and the 2 groups of fingers. In this infusion pump unit 8, the finger 2 sequentially presses the tube 4 from the upstream side (liquid supply (1111)) to the downstream side (liquid sending side), whereby the medicinal solution in the tube 4 is sent out.

In such an infusion pump unit 8, a pressure sensing piece 1 is provided in parallel to each finger 2 in the middle where a plurality of fingers 2 are arranged. This pressure sensing piece 1 is connected to two guide members 1 fixed to a pump unit 8.
By being slidably supported between the tubes 1 and 1 via a spring 10, the tube 4 can be displaced substantially perpendicularly to the tube 4 in response to expansion and contraction of the tube while always resisting the elasticity of the tube 4. A recessed groove 1a into which the infusion duplex 4 is loosely fitted is provided at the tip of the pressure sensing piece 1, and the tube 4 is guided by this recessed groove 1a.

Furthermore, in this device, a magnet 9 is fixed to the rear end of the pressure sensing piece 1, and a Hall sensor 3 is installed behind it, so that a change in the position of the pressure sensing piece 1 is converted into an electric signal as a displacement amount. Being able to do that. Note that as a means for detecting the positional displacement of the pressure sensing piece 1, a sensing coil method, a variable resistance method, or the like may be used.

In order to detect the infusion pressure using such a pressure detection piece 1, in the liquid feeding operation of the pump in which the position where the finger 2 presses the tube 4 sequentially moves from the upstream side to the downstream side, as shown in FIG. As shown in FIG. 2, when the pushing operation of the finger 2 moves to the middle 4C between the liquid supply side 4a and the liquid sending side 4b of the tube and that part is occluded, the pressure sensing piece 1 is pushed out to the tube 4 side. , as shown in FIG. 3 fbl, when the finger 2 presses the feeding side 4b of the tube 4 and that part is occluded, the pressure sensing piece 1 moves to the outside of the tube 4 due to the pressure of the liquid supply. Furthermore, as shown in Figure 3 (cl), if the finger 2 presses the liquid supply side 4a of the tube 4 and the part is occluded, the pressure will be detected by the pressure of the liquid supply. The piece 1 is pushed back outside the tube 4.

As described above, since the pressure sensing piece 1 is located in the middle of the 2 groups of fingers, the pressure sensing piece 1 is affected by the expansion of the tube 4 due to the pressure on the liquid supply side and the liquid sending side, depending on the pressing position of the finger 2 during liquid feeding. Displacement can be detected alternately. In this way, the pressure value when the displacement amount of the displaced pressure sensing piece l is converted into an electric signal is shown in FIG. 4 corresponding to each of the drawings in FIGS. As shown in the figure, when the displacement amount of the pressure sensing piece 1 is equal, the liquid supply side pressure and the liquid feeding side pressure are equal, and the displacement amount of the pressure sensing piece 1 is, for example, lower than the liquid feeding side pressure. If is larger, it can be known that an abnormality has occurred, such as dislodgement of the patient's thin tube on the fluid delivery side of the infusion tube 4.Also, if the amount of displacement of the pressure detection piece 1 is higher than the fluid delivery side pressure, for example, If the side pressure is larger, it can be known that an abnormality such as a blockage has occurred on the liquid supply side of the infusion tube 4.

Furthermore, since this device can extract the displacement of the pressure detection piece as an electrical signal, it is easy to connect a device that controls the operation of an infusion pump or a device that issues an alarm based on the above detection results to this device. This makes it possible to perform safe infusions.

[Effects of the Invention] As explained above, according to the infusion pressure detection device for an infusion pump of the present invention, the simple configuration in which only one pressure detection piece is incorporated into the infusion operation structure allows the infusion pressure detection device to detect pressure at the same location of the infusion tube. Since the pressure is detected on the suction side and the discharge side, there is an advantage that the detection characteristics can be obtained under the same conditions, unlike the conventional system which detects the pressure at various places on the suction side and the discharge side.

Further, according to the device of the present invention, it is possible to detect not only pressure abnormality due to occlusion of the infusion tube but also pressure fluctuation due to, for example, head pressure during infusion.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing the principle of the device of the present invention installed in a periphery flick type infusion pump. FIG. 2 is a schematic perspective view of an embodiment of the device according to the present invention. 3 fa) to fbl are diagrams for explaining the present invention in detail based on FIG. 1. FIG. Figure 4 is similar to Figure 3 (
It is a figure which shows the pressure when the displacement amount of the pressure detection piece corresponding to a)-fbl is converted into an electric signal. 1... Pressure detection piece 2... Finger 3... Hall sensor 4... Infusion tube 4a... Liquid supply side tube 4b... Liquid supply side tube 5... Holding member Fig. 6. ...Spring 7 for holding member...Pump body 8...Pump unit 9...Magnet 10...Spring 11 for pressure detection piece...Guiding member (a) Fig. 3(b) Fig. ( C) Procedural amendment March-22, 1991

Claims (1)

[Claims] In a peristaltic infusion pump in which a plurality of fingers are arranged to sequentially press an infusion tube from a liquid supply side to a liquid delivery side, the fingers are connected in the middle of the arrangement with an acting force that resists the elasticity of the infusion tube. An infusion pressure detection device for an infusion pump, characterized in that a pressure detection piece is provided, and a means for detecting displacement of the pressure detection piece alternately detects each of the liquid supply pressure and the liquid delivery pressure in the infusion. .