JPS6311028B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an infusion device for injecting various medicinal solutions, blood, etc. into a human body using a finger-type infusion pump.

In such an infusion device, it is necessary to strictly monitor whether or not the liquid is being reliably injected during the infusion. If this is not done, it will be overlooked that the infusion cannot be performed due to needle clogging, bending or dislodging of the infusion tube, etc., and there is a risk that blood will flow backwards. Furthermore, if the needle enters outside the blood vessel due to patient movement, adverse effects such as edema will occur. Furthermore, if the tube cracks, the liquid will leak to the outside. Furthermore, if the holding plate, which is opened and closed in a door manner and is used to press the tube against the finger, is accidentally opened, an excessive amount of liquid will flow.

In conventional devices, two detectors were provided to monitor the state of the infusion: one detects expansion and displacement of the tube due to abnormal blockage of the tube, and the other detects the opening of the holding plate. . However, with this method, even if the tube is not attached to the tube occlusion detector by mistake,
There was a problem in that no abnormality was detected as long as the holding plate was closed. Furthermore, since these two detectors are expensive, only a detector for detecting occlusion is often provided, which has led to a lack of safety.

The present invention provides an infusion device that solves the above problems, and embodiments of the present invention will be described below with reference to the drawings.

In the figure, an infusion tube 1 is held between a holding member 3 provided on a holding plate 2 and a finger 4, and the finger 4 is rotated by a motor 5 so that the infusion liquid flows in the direction of arrow c. ing. The press plate 2 is attached to be opened and closed like a door, and is closed in the direction of arrow a to press the tube 1, and opened in the direction of arrow b to release the pressure. Further, this pressing plate 2 is biased in the direction a by a spring 7 interposed between it and the substrate 6 to obtain the above-mentioned pressing force. A presser member 8 is provided integrally with the presser plate 2 at the lower part of the presser plate 2, that is, on the downstream side of the portion where the infusion tube 1 is held between the presser member 3 and the finger 4.
A pressure detector 9 such as a strain gauge is fixedly arranged in close proximity to and opposite to. By pressing and holding the tube 2 between the holding member 8 and the pressure detector 9 as shown in the figure, the pressure of the liquid pushed out by the finger 4 is detected.

The signal S _p indicating the detected pressure value above is the amplifier 1
0 to the comparison circuit 11, initial value storage circuit 12, and pressure increase calculation circuit 13. The initial value storage circuit 12 stores the pressure value when no liquid is being injected, and the subsequent arithmetic circuit 13 subtracts the pressure value when injecting from this initial pressure value. By canceling out temperature drift, etc., only the true pressure increase is determined. A signal S _ps indicating the increase in pressure determined by the arithmetic circuit 13 is applied to a comparator circuit 14 . Reference values S ₁ and S ₂ indicating pressure abnormality are supplied to this comparison circuit 14 from a closed value generation circuit 15 and an open value generation circuit 16, and are compared with the signal S _ps , respectively. In addition, the above occlusion value S ₁ is used for cases such as needle jams, etc.
This is a reference value when the load on the motor becomes heavy, and the above-mentioned open value _S2 is a reference value when the load on the motor becomes light, such as when the needle is pulled out or the tube is dislocated.

The comparison circuit 14 compares the signal S _ps with the signals S ₁ , S ₂ ,
When the signal substantially coincides with at least one of S ₃ , each of the above-mentioned abnormal states is detected and the detection signal S _A is applied to the alarm generation circuit 18 . This circuit 18 displays a display according to the abnormal state on a display section (not shown), and also sends a signal _Ss to a motor drive circuit 19 to stop the motor 5. According to the above, the infusion state can be constantly monitored.

On the other hand, the comparison circuit 11 compares the signal S _p with the signal S ₄ obtained from the presser plate opening value generation circuit 20 . This signal _S4 is a signal indicating the pressure value inside the tube 2 when the presser plate 2 is opened in the direction of arrow b.

The comparison circuit 11 applies the detection signal S _B to the alarm generating circuit 18 when the signal S _p becomes less than the signal S ₄ . This circuit 18 displays a display indicating that the presser plate 2 is released, and also sends a signal _Ss to the motor drive circuit 19 to stop the motor 5. According to the above, when the presser plate 2 is opened at the start of infusion,
Alternatively, it is possible to reliably detect that the presser plate 2 is erroneously opened during infusion. According to this embodiment, the above-mentioned abnormal state detection and presser plate 2
It is possible to detect two types of abnormal states with one pressure detector 9, including detection of open state.

Note that the release value S ₂ for detecting needle dropout, tube displacement, etc. and the presser plate release value S ₄ are generally different in magnitude. Since the pressure becomes approximately zero when the presser plate 2 is released, the above-mentioned S ₄ is a value indicating approximately zero. Therefore,
Infusion is performed under the condition that the signal S _p indicating pressure is S _p ≠ 0, and under this condition, the signal S _ps is compared with S ₂ and S ₁ , respectively, and the needle is removed, the tube is dislodged, the needle is When a blockage or the like occurs, an alarm is generated according to the signal S _A. Further, when S _p ≦S ₄ , an alarm indicating that the presser plate 2 has been released is generated in response to the signal S _B.

As described above, the present invention has a movably provided holding plate 2 and a finger 4, and the holding plate 2 and the finger 4 are moved to a predetermined position (the position shown in FIG. 2). In the infusion device, the liquid in the infusion tube 1 is transported by driving the fingers 4 while holding the infusion tube 1 between the holding plate 2 and the infusion tube 1.
and the above-mentioned infusion tube 1 with the above-mentioned finger 4
The presser plate 2 is located downstream of the clamping portion of the
a holding member 8 integrally provided with the holding member 8; and a fixed first member that clamps the infusion tube 1 together with the holding member 8 and detects the fluid pressure in the infusion tube 1.
The detection means 9 compares the hydraulic pressure S _p or S _ps detected by the first detection means with the first reference value _S1 , and when the hydraulic pressure becomes larger than the first reference value. Second detection means 1 that outputs the first abnormal signal S _A
5 and 14, the hydraulic pressure detected by the first detection means is compared with the second reference value _S2 , and when the hydraulic pressure becomes smaller than the second reference value, a second abnormal signal is generated.
Third detection means 16, 14 that output S _A , the hydraulic pressure obtained from the first detection means, and a third reference value indicating that the presser plate is not at the predetermined position.
S ₄ and outputs a third abnormal signal S _B when the hydraulic pressure becomes smaller than the third reference value.
This relates to an infusion device comprising detection means 20 and 11.

Therefore, according to the present invention, two abnormal conditions can be detected using one pressure detector: abnormalities such as needle dropout, tube displacement, and needle jam during infusion, and abnormalities such as the erroneous release of the presser plate. It can be detected accurately and two abnormal states can be distinguished. Thereby, infusion can be performed more safely than before.

[Brief explanation of the drawing]

The drawing is a block diagram showing an embodiment of the invention. In addition, in the symbols used in the drawings, 1...infusion tube, 2...pressing plate, 4...finger,
9...Pressure detector, 11, 14...Comparison circuit, 1
5... Open value generation circuit, 16... Blocked value generation circuit, 17... Abnormal value generation circuit, 20... Presser plate open value generation circuit.

Claims (1)

[Scope of Claims] 1. A movable holding plate and a finger are provided, and the finger is driven while the infusion tube is held between the holding plate and the finger which have been moved to a predetermined position. In the infusion device configured to transport the liquid in the infusion tube, the holding member is integrally provided with the holding plate on the downstream side of the clamping portion of the infusion tube between the holding plate and the finger; , a fixed first detection means that clamps the infusion tube with the holding member and detects the fluid pressure in the infusion tube; and the fluid pressure detected by the first detection means and a first reference value. a second detection means that compares the hydraulic pressure detected by the first reference value and outputs a first abnormal signal when the hydraulic pressure becomes larger than the first reference value; a third detection means that compares the hydraulic pressure with a reference value and outputs a second abnormal signal when the hydraulic pressure becomes smaller than the second reference value, and a hydraulic pressure obtained from the first detection means; A fourth detection unit that compares the pressure plate with a third reference value indicating that the presser plate is not in the predetermined position, and outputs a third abnormality signal when the hydraulic pressure becomes smaller than the third reference value. An infusion device comprising means.