JP5141004B2 - Condition detection device - Google Patents

Description

  The present invention relates to a state detection device that detects a state of a liquid flowing in a pipe in a state of being interposed in the pipe.

  As an example of a state detection device for monitoring the state in a circuit through which liquid flows, a pressure measurement device that detects the pressure of the liquid flowing in the circuit by displacement of a diaphragm provided in the detection device (Patent Document 1) And an optical detection device that detects the degree of turbidity of the liquid and the concentration of a specific component present in the liquid based on the light transmittance.

  Since these detection devices cannot accurately detect pressure and light transmittance when bubbles are present in the detection device, it is necessary to remove bubbles inside the detection device.

  In particular, when these detection devices are incorporated in a circuit that extracts and processes blood outside the body, such as a blood circuit, the pressure of the liquid flowing in the circuit and the light transmittance are important indicators related to human life. Accurate detection is desired.

  The technical background will be described below by taking a blood circuit and a dialysis monitoring device as examples.

  Hemodialysis is a treatment method in which blood derived from a patient is circulated through a blood purifier (dialyzer) to remove excess water and waste products in the blood. The flow path connected to the patient is called a blood circuit, and blood drawn from the patient by a blood pump arranged in the dialysis monitoring device flows in this circuit, and is purified by the blood purifier connected thereto, and again. Returned to the body. A hollow fiber type semipermeable membrane is accommodated inside the blood purifier, blood is circulated inside the hollow fiber, dialysate is circulated outside the hollow fiber, and blood is diffused and filtered through the semipermeable membrane. Move unnecessary substances in the dialysate and remove them from the blood.

  In general, blood and dialysate are circulated in opposite directions to improve dialysis efficiency during treatment. Moreover, in order to remove bubbles from the dialysate, the dialysate flows from the lower side to the upper side of the hollow fiber of the blood purifier. Therefore, blood circulates from the upper side to the lower side in the blood purifier so as to counter flow with the dialysate.

  On the other hand, before the treatment is performed, a preparatory work for replacing the air in the blood circuit or the blood purifier with physiological saline or the like and circulating the blood in the circuit is required. Of these preparatory operations, filling the circuit with physiological saline using the blood pump of the dialysis monitoring apparatus after the circuit is attached to the dialysis monitoring apparatus is called “priming”. In the priming operation, liquid is circulated from the lower side to the upper side in the blood flow path of the blood purifier, in which air tends to remain, so that air in the circuit can be easily removed. That is, it is required to circulate the liquid from the upper side to the lower side at the time of treatment, and from the lower side to the upper side at the time of priming, and the flow of the liquids in both directions is upside down. For this reason, at the time of priming, the blood purifier is inverted, and pre-treatment such as liquid replacement is performed with the blood purifier inlet positioned downward and the blood purifier outlet positioned upward. . Further, when shifting to treatment, an operation of rearranging in the correct direction is necessary, and when performing treatment of a plurality of dialysis patients at the same time, the operation becomes very complicated.

  Therefore, recently, a priming method has been proposed which is devised so as not to require human intervention as much as possible from the initial state in which the blood circuit is connected to the dialysis monitoring device to the start of treatment.

  As one of the priming methods, for example, a method is proposed in which the blood circuit is preset in the dialysis monitoring device and the pump is rotated in the reverse direction to generate a flow in the direction opposite to the flow direction of the liquid flowing at the time of treatment. Has been. During priming, the pump is rotated in the reverse direction to generate a reverse flow, so that the blood purifier can be filled from the bottom to the top with the blood purifier set in the direction during treatment. It becomes.

However, for example, in a pressure detection device having a structure as shown in FIG. 8, air can be easily expelled in the direction of the arrow (forward direction) in the figure, but air is expelled in the reverse direction as in the priming. Since the other problem of becoming difficult occurs, the inventors of the present application have arranged the liquid inlet and the outlet from which the liquid flows out at the upper part of the liquid storage part in which the liquid is stored. A state detection device (pressure detection device) that can easily remove bubbles regardless of whether the direction is forward or reverse is proposed separately.
Japanese Patent No. 3526965

  However, in the state detection device configured to easily remove bubbles in both the forward and reverse bidirectional liquid flows, depending on the flow velocity of the liquid passing through the pipe and the viscosity of the liquid, the liquid is stored in the liquid storage section. Found to stay.

  For example, when the circulating liquid is blood, problems such as blood coagulation caused by retention, and accurate pressure cannot be detected occur. In addition, blood that has been led out of the body at the end of dialysis treatment is introduced into the body. When returning, the problem that the staying part cannot be returned into the body occurs.

  In view of the above problems, the present invention aims to provide a state detection device that can easily remove bubbles from a bidirectional liquid flow and can suppress the occurrence of stagnation as much as possible. To do.

  In the above description, the dialysis monitoring device has been described as an example. However, the same conventional devices are generally used to extract and process body fluids outside the body, such as blood purification monitoring devices such as blood filtration devices, heart-lung machines, and blood concentration devices. Have the technology and challenges.

  In order to achieve the above object, a state detection device according to the present invention includes a liquid storage section that is disposed in a pipe and stores liquid flowing in the pipe, and an inflow section that allows liquid to flow into the liquid storage section. An outflow part that causes liquid to flow out from the liquid storage part, an inflow port that is a rear end part of the inflow part above the central part in the vertical direction of the liquid storage part in a normal attachment state, and a front end part of the outflow part An inflow direction axis indicating an inflow direction of the liquid flowing in from the inflow port through the center of the inflow port, and the outflow from the outflow port through the center of the outflow port. The angle formed by the outflow direction axis indicating the outflow direction of the liquid is less than 180 degrees.

  As a result, at least a part of the inflowed liquid enters the liquid storage part, and the liquid existing in the liquid storage part can be stirred. Therefore, it is possible to suppress the retention of the liquid generated in the liquid storage unit.

  The angle formed by the outflow part with respect to the inflow part is preferably 140 degrees or more and 170 degrees or less.

As a result, it is possible to effectively discharge the bubbles existing inside the liquid storage part while suppressing the retention of the liquid in the liquid storage part.

  Moreover, the said objective can be achieved also by the state detection apparatus shown next. That is, the state detection device according to the present invention includes a liquid storage part that is disposed in a pipe and stores liquid flowing in the pipe, an inflow part that allows liquid to flow into the liquid storage part, and liquid from the liquid storage part. An inflow port that is a rear end portion of the inflow portion, and an outflow port that is a front end portion of the outflow portion above the central portion in the vertical direction of the liquid storage portion in a normal attachment state. An inflow direction axis indicating an inflow direction of the liquid flowing in from the inflow port through the center of the inflow port, and an outflow direction of the liquid flowing out of the outflow port through the center of the outflow port. The inflow portion and the outflow portion are arranged so as not to contact the illustrated outflow direction axis.

  Thereby, avoiding a state where all of the liquid flowing in from the inflow port directly flows out from the outflow port, the liquid flowing in from the inflow port can flow out from the outflow port while stirring the liquid in the liquid storage part, It is possible to suppress stagnation of the liquid generated in the liquid storage unit.

  Further, it is preferable that the liquid storage part has a substantially cylindrical shape, and the inflow port and the outflow port are disposed on a peripheral wall of the liquid storage part.

  As a result, the liquid flowing into the liquid storage part flows while swirling along the peripheral wall, so that the entire liquid in the liquid storage part can be easily stirred. In addition, it is possible to easily achieve both the suppression of liquid retention and the removal of bubbles.

  Needless to say, the retention prevention effect can be enhanced by integrating the two independent inventions.

  Regardless of whether the liquid flow is in the forward direction or in the reverse direction, it is possible to effectively remove bubbles and to suppress the retention of the liquid in the liquid storage portion as much as possible.

  Next, a pressure detection device which is an embodiment of the state detection device of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing a pressure detection device with one end face opened.

  A pressure detection device 1 shown in the figure is a part of a device that is interposed in a blood circuit or a dialysate circuit used in a dialysis monitoring device and detects the pressure of blood or dialysate in the circuit in real time. And a T-shaped housing 3 having a cylindrical liquid storage portion 2 at the center.

  FIG. 2 is a front view of the pressure detection device. In addition, the figure has shown the attitude | position in the normal attachment state of a pressure detection apparatus. FIG. 3 is a cross-sectional view of the pressure detector 1 in FIG.

  The pressure detection device 1 as the state detection device shown in FIGS. 2 and 3 includes an inflow portion 4 and an outflow portion 5 that communicate the liquid storage portion 2 and the outside of the housing 3.

  The inflow part 4 and the outflow part 5 are flow paths that are directly connected to the liquid storage part 2, and in the case of this embodiment, are linearly provided from the outside of the housing 3 toward the liquid storage part 2. It is a flow path. For convenience, the inflow portion 4 and the outflow portion 5 and the inflow port 8 and the outflow port 9 described later are fixed, but a flow in a direction opposite to the flow of liquid during use is generated to perform priming. The liquid is circulated in the circuit and the purifier. During priming or the like, the inflow portion 4 functions as an outflow portion, and the inflow port 8 functions as an outflow port. Similarly, the outflow portion 5 functions as an inflow portion, and the outflow port 9 functions as an inflow port.

  In the case of the present embodiment, the angle formed by the outflow portion 5 with respect to the inflow portion 4 (since the inflow portion 4 and the outflow portion 5 are linear, the same as the angle formed by the inflow direction axis and the outflow direction axis) θ is 160. The degree is adopted. Thus, when the inflow part 4 and the outflow part 5 are arranged at a predetermined angle, a part of the inflowed liquid reaches the lower part of the liquid storage part 2 and is present in the lower part of the liquid storage part 2. Thus, the liquid can reach the outflow part 5, and the liquid in the liquid storage part 2 can be stirred to prevent the liquid from staying.

  Although the angle formed by the inflow portion 4 and the outflow portion 5 is not limited, when the angle θ formed by the outflow portion 5 with respect to the inflow portion 4 is within a range of 170 degrees or less, the inflow portion 4 Even when the flow rate of the inflowing liquid is small, it is desirable because it is possible to prevent staying below the liquid storage part at a position away from the inlet or outlet.

  Moreover, the inflow part 4 and the outflow part 5 are each provided with the enlarged diameter part 6 in the outer side edge part. The enlarged diameter portion 6 is a portion into which an end portion of a soft pipe (not shown) that is a liquid flow path is forcibly inserted. A connector may be provided at the outer end of the inflow portion 4 or the outflow portion 5 so as to be detachable from an external pipe.

  As can be seen from FIGS. 2 and 3, the liquid reservoir 2 has a cylindrical shape. And the liquid storage part 2 is formed by surrounding the surrounding wall and its one end part by the housing | casing 3 integrally. In addition, the other end of the liquid storage unit 2 is in an open state without being closed by the housing 3.

  In addition, the other end part of the liquid storage part 2 which is in an open state is sealed with a diaphragm which will be described later.

  The housing 3 is entirely formed of a transparent resin so that the state of the liquid inside can be seen. Thereby, the state of the blood, the state of the dialysate, the state of the liquid flow, and the like can be visually confirmed during dialysis.

  Further, since the peripheral wall portion of the casing 3 forming the liquid storage unit 2 is transparent, light can be transmitted to the liquid stored in the liquid storage unit 2. Thus, for example, if a device capable of detecting transmitted light is interposed in the dialysate circuit and a change in the amount of transmitted light passing through the liquid storage unit 2 is detected, the dialysis solution becomes turbid, that is, dialysate It is possible to determine the presence or absence of blood leakage (blood leakage). In addition, since the liquid storage part 2 is a knob-like part having a larger volume than a tube or the like, the distance through which light passes through the liquid stored in the liquid storage part 2 can be increased, and the dialysis liquid becomes turbid. It becomes possible to improve the sensitivity etc. which detect etc.

  An inflow port 8 that is an end portion of the inflow portion 4 and an outflow port 9 that is an end portion of the outflow portion 5 are provided on the peripheral wall surface of the liquid storage portion 2. As can be seen from FIGS. 2 and 3, the inflow port 8 and the outflow port 9 are disposed above the center in the direction of the vertical axis 10 passing through the center of the liquid storage unit 2, and are disposed at or near the top. Has been. Further, the pressure detection device 1 is arranged so as to be symmetric with respect to the vertical axis 10 and shifted in the thickness direction (vertical direction in FIG. 3). That is, an inflow direction axis indicating the inflow direction of the liquid flowing in from the inflow port 8 through the center of the inflow port 8, and an outflow direction indicating the outflow direction of the liquid flowing out of the outflow port 9 through the center of the outflow port 9. The inflow portion 4 and the outflow portion 5 are arranged so as not to contact the shaft.

  Thus, by not arranging the inflow portion 4 and the outflow portion 5 on the same surface, a part of the liquid flowing in from the inflow portion 4 does not directly flow out of the outflow portion 5, and the inside of the liquid storage portion 2 The liquid can be agitated to prevent the liquid in the liquid storage unit 2 from staying. Further, unlike the present embodiment, the inflow portion 4 and the outflow portion 5 are not arranged on the same surface, and a predetermined angle θ (FIG. 2) is provided between the inflow portion 4 and the outflow portion 5. Thus, the retention preventing effect of the liquid storage unit 2 can be further enhanced.

  Further, as shown in FIG. 2, the upper end portion of the inflow port 8 and the upper end portion of the outflow port 9 are disposed at substantially the same position in the horizontal direction (left and right direction in FIG. 2). In addition, the top of the liquid storage unit 2 is arranged at the same position so that it is substantially at the same position (in the horizontal direction). As described above, each upper end and the top are arranged on the same plane, so that bubbles stopped at the upper end of the liquid storage unit 2 are easily transported to the outlet 9 by the liquid flowing in from the inlet 8. . Accordingly, it is possible to easily remove the air bubbles inside the liquid storage unit 2 without retaining the air bubbles inside the liquid storage unit 2. In the case of the present embodiment, since the liquid storage part 2 has a cylindrical shape, the top exists in a linear shape.

  As shown in FIGS. 2 and 3, the pressure detection device 1 has the shape of the liquid storage unit 2, the liquid storage so that the liquid flows in the same state even if the inflow unit 4 and the outflow unit 5 are replaced. The positional relationship between the portion 2 and the inflow portion 4 and the outflow portion 5, the inclination of the inflow portion 4 and the outflow portion 5, the positions of the inflow port 8 and the outflow port 9 are symmetrical in FIG. 2, and are axially symmetric in FIG. Has been made. In this way, by making the shape of each part symmetrical and making the positional relationship of each part symmetrical, even if the inflow direction of the liquid is reversed, the retention of the liquid in the liquid storage part 2 is prevented and effective as described above. It is possible to eliminate bubbles. Accordingly, it is possible to easily remove bubbles inside the pressure detection device even during priming in which the liquid flow direction is reversed.

  4A and 4B are views showing a state in which the diaphragm 11 as a pressure detection unit is attached to the housing, in which FIG. 4A is a front view, and FIG. 4B is a cross-sectional view showing a state cut along line AA shown in FIG. It is.

  As shown in the figure, one end of the cylindrical liquid storage part 2 is sealed by a diaphragm 11 that is deformed by the pressure of the liquid existing in the liquid storage part 2. The diaphragm 11 is attached to the housing 3 by a pressing ring 12 for preventing the diaphragm 11 from falling off.

  The load cell 13 connected to the diaphragm 11 is a sensor for detecting a displacement near the center of the diaphragm 11 as a pressure.

  FIG. 5 is a perspective view showing a blood purification monitoring device 14 suitable for continuous and slow therapy, a blood circuit 17 and a dialysate circuit 18 (replacement fluid circuit, filtrate circuit) attached thereto.

  As shown in the figure, the pressure detection device 1 is disposed in a blood circuit 17 before and after a blood purifier 19 used for blood purification, and detects the pressure of blood during treatment in real time.

  Further, the pressure detection device 1 is also disposed in the dialysate circuit 18 so that the pressure of the dialysate is detected in real time. Further, a light emitting unit 20 and a light receiving unit 21 are provided on both sides of the pressure detecting device 1 of the dialysate circuit 18, and the intensity of light emitted from the light emitting unit 20 is detected by the light receiving unit 21, thereby allowing dialysis. The presence or absence of blood leakage in the liquid is confirmed. In this way, by monitoring the concentration change (change in the amount of received light) of blood and specific components present in the liquid storage unit 2 using the pressure detection device 1, the state of the dialysate can be observed together with the pressure. It becomes possible.

<Example>
Next, an experiment for confirming the effect of the present invention will be described.

  In order to verify the effect of the present invention, the following three experiments were conducted.

  (1) A liquid circuit including a pressure detection device is assembled using a predetermined pipe, and after filling the circuit with physiological saline using a pump, the presence or absence of bubbles remaining in the pressure detection device is visually confirmed. (Confirmation of bubble removal performance).

  (2) In a state where physiological saline filled in the circuit is circulated by a pump, air bubbles are fed from a co-injection port (not shown), and the state of removal of the air bubbles in the pressure detector is visually observed. (Confirmation of bubble removal performance).

  (3) The circuit once filled with bovine blood was replaced with physiological saline, and the remaining state of the bovine blood in the pressure detector after a predetermined time was visually observed (confirmation of the staying state).

  In addition, the pressure detecting device used is the one in which the positional relationship between the inlet and the outlet shown in FIG. 3 is shifted in the vertical direction in FIG. 3 (with a shift), and the angle of the outlet is changed with respect to the inlet. The angle of the outflow portion 5 with respect to the inflow portion 4 is changed by the positional relationship between the inflow port 8 and the outflow port 9 shown in FIG. 6B (the inflow direction axis and the outflow direction axis intersect: no deviation).

  FIG. 7 is a table showing the results of the experiment.

  As shown in the table, in the staying state, as the angle θ formed by the inflow portion 4 and the outflow portion 5 decreases, the residual amount of bovine blood in the pressure detection device after a predetermined time has tended to decrease. It showed that the prevention effect was great. On the other hand, when θ is greater than 170 degrees, the residual amount of bovine blood is greatly increased, and there are cases where it cannot be almost replaced.

  Furthermore, even when θ is greater than 170 degrees, if there is a deviation in the positional relationship between the inlet and the outlet, the remaining amount of bovine blood will be smaller than if there is no deviation, and the positional relationship between the inlet and the outlet will be shifted. Found to tend to improve retention.

  From the above, it can be concluded that if the angle θ of the outflow part with respect to the inflow part is set in the range of 140 degrees or more and 170 degrees or less, both the bubble removal effect and the stay prevention effect can be enjoyed.

  As mentioned above, although embodiment of this invention was described, this invention is not necessarily limited to the said embodiment.

  For example, even a state detection device that does not include a pressure detection unit (diaphragm) is included in the present invention. For example, if the state detection device includes a transparent housing that forms a liquid storage part, a liquid storage part that can easily remove bubbles regardless of the liquid flow direction can be used, and light can be emitted to the liquid storage part. By transmitting the light, it is possible to ensure a long distance that the liquid interferes with the light, and to detect the turbidity of the liquid with high sensitivity.

  Further, the pressure may be detected not only by measuring the pressure accurately using a diaphragm, but also by using what is called a pillow to roughly detect only the positive or negative pressure. A pillow is generally used in a blood circuit for blood purification, and is a tube having a flexible diameter-expanded portion that is shaped and processed into an elliptical cross section in the axial direction of a liquid flow. Thus, the negative pressure state in the blood circuit can be confirmed by the degree of collapse of the enlarged diameter portion.

  Further, the shape of the liquid storage part 2 is not limited to a cylindrical shape, but may be a spherical shape. Moreover, even if it employ | adopts arbitrary shapes, such as a rectangle, it is included by this invention.

  Further, the shape of the housing 3 is not limited to the T-shape, and any shape can be adopted, and for example, a cylindrical shape along the shape of the liquid storage unit 2 may be used.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a state detection device that detects the state of a liquid flowing in a tube, and in particular, the state detection device according to the present invention is suitably employed for a body fluid derivation device that extracts and processes body fluid outside the body. .

It is a perspective view which shows the pressure detection apparatus from which the diaphragm was removed. It is a front view of the pressure detection device. It is sectional drawing which desires the II line cross section of a pressure detection apparatus from the downward direction. It is the front view (a) which shows the state which attached the diaphragm as a pressure detection part to a housing | casing, and is sectional drawing (b). It is a perspective view which shows the monitoring apparatus for blood purification, the blood circuit attached to this, and a dialysate circuit. It is a figure which shows another aspect of a pressure detection apparatus. It is a table | surface which shows the result of experiment. It is a perspective view which shows the conventional pressure detection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pressure detection apparatus 2 Liquid storage part 3 Housing | casing 4 Inflow part 5 Outflow part 6 Diameter expansion part 8 Inlet 9 Outlet 10 Vertical axis | shaft 11 Diaphragm 12 Press ring 13 Load cell 14 Blood purification monitoring device 17 Blood circuit 18 Dialysate circuit 19 Blood purifier 20 Light emitting part 21 Light receiving part

Claims (2)

A liquid storage part that is disposed in a pipe and stores liquid flowing in the pipe; an inflow part that allows liquid to flow into the liquid storage part; an outflow part that causes liquid to flow out of the liquid storage part; and the inflow part, And an inflow port which is a rear end portion of the inflow portion above the central portion in the vertical direction of the liquid storage portion in a mounting state in which the flow path including the outflow portion is up and the liquid storage portion is down And a state detection device comprising an outlet that is a tip of the outflow part,
The liquid storage part has a cylindrical shape,
The inflow port and the outflow port are disposed on a peripheral wall of the liquid storage part,
An angle formed between an inflow direction axis indicating the inflow direction of the liquid flowing in from the inflow port through the center of the inflow port and an outflow direction axis indicating the outflow direction of the liquid flowing out of the outflow port through the center of the outflow port. There 140 degrees or more state, and are less than 180 degrees,
The state detecting device , wherein the inflow portion and the outflow portion are arranged so that the inflow direction axis does not contact the outflow direction axis .   The state detection device according to claim 1, wherein an angle formed by the inflow direction axis and the outflow direction axis is 170 degrees or less.

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