JP6772447B2 - Blood circuit with pressure measuring unit - Google Patents

Description

The present invention relates to a blood circuit having a pressure measuring unit, and more specifically to a blood circuit having a pressure measuring unit using a flexible membrane.

Conventionally, the blood circuit has been described in, for example, US Pat. No. 8,924,414 (Patent Document 1), JP-A-61-143069 (Patent Document 2), US Pat. No. 6,526,357 (Patent Document 3), JP-A-5. It is disclosed in Japanese Patent Application Laid-Open No. -23393 (Patent Document 4), Japanese Patent Application Laid-Open No. 9-24026 (Patent Document 5), and Japanese Patent Application Laid-Open No. 58-153841 (Patent Document 6).

U.S. Pat. No. 8092414 Japanese Unexamined Patent Publication No. 61-143069 U.S. Pat. No. 6,526,357 Japanese Unexamined Patent Publication No. 5-23393 Japanese Unexamined Patent Publication No. 9-24024 Jikkai Sho 58-153841

The blood circuit described in Patent Document 1 is provided with a pressure detection chamber. The pressure sensing chamber has a flexible membrane, which divides the chamber into two spaces. The fluid pipeline communicates with one space, and one space is isolated from the other. The other space is connected to the pressure measuring device. The chamber is provided with channels to prevent obstruction of blood flow.

When a channel is provided in the chamber as in Patent Document 1, the channel may become a resistance to blood flow.

Therefore, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a blood circuit that does not obstruct the flow of blood.

A blood circuit according to one aspect of the present invention is a blood circuit having a pressure measuring unit connected to a pressure measuring device, wherein the pressure measuring unit includes a housing, a flexible film provided in the housing, and the like. The pressure of the blood is measured by flowing blood into the housing so as to be adjacent to the flexible film and changing the gap between the flexible film and the housing according to the pressure of the blood. It can further include a bypass path provided in parallel with the flexible membrane and separated from the housing so that blood can flow when the flow path in the housing is blocked.

In the blood circuit configured in this way, even when the flow path in the flexible membrane is blocked, blood flows through the bypass path, so that it is possible to prevent the entire blood circuit from being blocked. Further, the bypass path is provided at a distance from the housing, so that the influence of the bypass path on the flow path of the housing is reduced. As a result, it becomes possible to provide a blood circuit that does not obstruct the flow of blood.

A blood circuit according to another aspect of the present invention is a blood circuit having a pressure measuring unit connected to a pressure measuring device, wherein the pressure measuring unit has a tubular housing and a housing inside the tubular housing. A non-cylindrical tubular flexible film provided with a gap formed between them is provided, blood is allowed to flow in the tube of the flexible film, and the flexible film expands in response to the pressure of the blood. The pressure of blood can be measured by reducing the gap between the housing and the flexible membrane, and the pressure is provided in parallel with the flexible membrane so that blood can flow when the flow path in the flexible membrane is blocked. It also has a bypass road.

In the blood circuit configured in this way, even when the flow path in the flexible membrane is blocked, blood flows through the bypass path, so that it is possible to prevent the entire blood circuit from being blocked. Further, since blood flows in the cylinder of the flexible membrane, even if the bypass path is provided, the influence of the bypass path on the flow path of the housing is reduced. As a result, it becomes possible to provide a blood circuit that does not obstruct the flow of blood.

A blood circuit according to still another aspect of the present invention is a blood circuit having a pressure detection unit, the pressure detection unit is a flexible bag body, and when the flow path in the pressure detection unit is blocked. A bypass path provided in parallel with the diaphragm is further provided so that blood can flow through the diaphragm.

Preferably, if the flow path in the housing or the pressure detector is less than a predetermined pressure, the flow of blood to the bypass path is blocked, and if the flow path in the housing or the pressure detector exceeds a predetermined pressure, blood is discharged. A control unit for flowing to a bypass path is further provided.

In this case, since the bypass path is not used during normal operation (the flow path is less than a predetermined pressure), the pressure can be reliably measured by the housing and the flexible membrane.

It is a schematic diagram of the blood circuit provided with the pressure measuring part according to the embodiment of this invention. It is a front view of the pressure measuring part and the bypass path for negative pressure measurement according to Embodiment 1. FIG. FIG. 5 is a plan view of a pressure measuring unit for measuring negative pressure according to the first embodiment. It is sectional drawing along the IV-IV line in FIG. It is sectional drawing which shows the part surrounded by V in FIG. 4 enlarged. It is a side view of the pressure measuring part for negative pressure measurement according to Embodiment 1. FIG. FIG. 5 is an exploded perspective view of a pressure measuring unit for measuring negative pressure according to the first embodiment. It is a top view of the housing of the pressure measuring part for measuring the negative pressure according to Embodiment 1. FIG. It is sectional drawing along the IX-IX line in FIG. It is a side view of the housing of the pressure measuring part for negative pressure measurement according to Embodiment 1. FIG. It is a front view of the joint part of the pressure measuring part for negative pressure measurement according to Embodiment 1. FIG. It is sectional drawing along the XII-XII line in FIG. It is a side view of the joint part of the pressure measuring part for negative pressure measurement according to Embodiment 1. FIG. It is a front view of the flexible film of the pressure measuring part for the negative pressure measurement according to Embodiment 1. FIG. It is sectional drawing along the XV-XV line in FIG. FIG. 5 is a plan view of a pressure measuring unit and a bypass path for measuring negative pressure according to the first embodiment. It is sectional drawing along the XVII-XVII line in FIG. It is a front view of the pressure measuring part according to Embodiment 2.

(Embodiment 1)
With reference to FIG. 1, the blood circuit is a pressure transducer that measures the blood pressure of a blood inlet 1 for extracting blood from a patient, a blood loss measuring site 2 connected to the blood inlet 1, and a blood loss measuring site 2. 3. Blood pump 4 that pressurizes the blood discharged from the blood removal measurement site 2, PD pressure measurement site 5 located on the downstream side of the blood pump 4, and pressure for measuring blood pressure at the PD (Pre-dialyzer) pressure measurement site 5. The dialyzer 8 that receives the blood discharged from the transducer 6 and the PD pressure measurement site 5 via the dialyzer blood inlet 7a, the venous pressure measurement site 11 located on the downstream side of the dialyzer blood outlet 7b of the dialyzer 8, and the venous pressure measurement. It has a pressure transducer 12 for measuring the blood pressure at the site 11, and a blood outlet 13 for returning blood to the patient.

The dialyzer 8 is connected to the dialyzer main body 10 via the dialysate outlet 9a and the dialysate introduction port 9b, and uses the dialysate to remove waste products in the blood and adjust the water content in the blood.

With reference to FIGS. 2, 16 and 17, the pressure measuring unit 100 is provided at the blood pressure loss measuring site 2 in FIG. 1, which is a negative pressure site. The pressure measuring unit 100 includes a housing 110 and blood lines 210 and 220 connected to the housing 110.

The housing 110 is connected to a joint component 111 on the inlet side where blood is introduced and a joint component 112 on the outlet side where blood is discharged. A blood line 210 is inserted into the joint component 111 on the inlet side, and a blood line 220 is inserted into the joint component 112 on the outlet side. In the embodiment, the housing is formed by one member, but two half-split members may be combined to form the housing.

The housing 110 is provided with a pressure measurement port 140, and a pressure monitor line 240 is connected to the pressure measurement port 140. The connector 241 at the tip of the pressure monitor line 240 is connected to the pressure transducer. A clip 242 is attached to the pressure monitor line 240, and the pressure monitor line 240 can be closed.

A bypass path 290 is provided in parallel with the pressure measuring unit 100. The blood line 210 is provided with a branch portion 281, the blood line 220 is provided with a branch portion 282, and the branch portion 281 to the branch portion 282 serve as a bypass path 290.

By providing the bypass path 290, even if the pressure measuring unit 100 is blocked, blood flows in the bypass path 290 provided in parallel with the pressure measuring unit 100, so that it is possible to suppress the retention of blood in the blood circuit.

The bifurcation portions 281,282 may always allow blood to flow through the bypass path 290, or may allow blood to flow through the bypass path 290 only when the pressure measuring unit 100 is blocked. In order to allow blood to flow into the bypass path 290 only when the pressure measuring unit 100 is blocked, the branching units 281,282 are opened when the flow rate in the pressure measuring unit 100 is measured and the flow rate becomes equal to or less than a predetermined value. May be good. That is, the branch portions 281,282 block the flow of blood to the bypass path 290 when the flow path in the housing 110 is less than the predetermined pressure, and the blood flow path in the housing 110 becomes the predetermined pressure or more. Is a control unit that allows the blood to flow to the bypass path 290.

With reference to FIG. 3, the joint component 111 on the inlet side and the joint component 112 on the outlet side provided in the housing 110 are provided on the same straight line, and the joint component 111 on the inlet side faces the joint component 112 on the outlet side. Blood can flow smoothly.

The cylindrical housing 110 is long along the direction from the joint component 111 on the inlet side to the joint component 112 on the outlet side. The housing 110 is provided with a pressure measurement port 140 extending so as to be orthogonal to the direction from the joint component 111 on the inlet side to the joint component 112 on the outlet side. The pressure measurement port 140 is arranged non-parallel to the joint component 111 on the inlet side and the joint component 112 on the outlet side.

With reference to FIG. 4, the inside of the housing 110 is hollow, and the space extends from the joint component 111 on the inlet side to the joint component 112 on the outlet side. At both ends of the housing 110, engaging portions 113, 114 that engage with the joint parts 111, 112 on the inlet side and the outlet side are provided.

The distance between the inner peripheral surface of the housing 110 and the flexible film 120 is approximately 0 to 2 mm. The flexible film 120 divides the chamber 102 formed by the housing into two spaces. The chamber 102 is divided into a blood chamber 150 through which blood passes and an air chamber 160 in which air for pressure measurement is present.

Blood is introduced into the blood chamber 150 from the joint component 111 on the inlet side, and the blood in the blood chamber 150 is discharged from the joint component 112 on the outlet side. Since the flexible membrane 120 has elasticity and can be deformed in the direction of being deformed inward and deforming outward, the volume of the blood chamber 150 is variable.

The air chamber 160 is formed in a slight gap between the flexible membrane 120 and the housing 110 in FIG. Since the flexible membrane 120 is deformable inward, the volume of the air chamber 160 is also variable.

The central axis of the cylindrical flexible film 120 is parallel to the line 111a from the joint component 111 on the inlet side to the joint component 112 on the outlet side.

The pressure measurement port 140 communicates with the air chamber 160, but not with the blood chamber 150. When the flexible film 120 is displaced according to the flow of blood in the blood chamber 150 and the volume of the air chamber 160 changes, this volume change is transmitted to the transducer, so that the blood pressure can be measured by the transducer. It is possible.

A plurality of ribs may be provided on the inner peripheral surface of the housing 110. This rib has a function of increasing the strength of the housing 110 and stabilizing the posture of the housing 110.

Further, the ribs make it easier to insert the flexible film 120 into the housing 110. The flexible film 120 is close to and not in close contact with the inner peripheral surface of the housing 110.

With reference to FIG. 5, the outlet-side joint component 112 is engaged with the engaging portion 114 of the housing 110. A flexible film 120 is sandwiched between the joint component 112 on the outlet side and the tubular portion of the housing 110. As a result, the flexible film 120 is fixed to the housing 110. The merit of the fixing method of FIG. 5 is that there are many sealing surfaces and the risk of leakage is low.

With reference to FIG. 6, the joint component 111 on the inlet side is fitted with the engaging portion 113. The pressure measurement port 140 projects toward the outer periphery of the engaging portion 113. In this figure, the outer shape of the engaging portion 113 is circular, but it may be polygonal.

With reference to FIG. 7, the flexible membrane 120 is inserted into the chamber 102 in the housing 110. The natural length of the flexible film 120 is longer than the length of the housing 110, and the end portion of the flexible film 120 is folded back between the engaging portion 113 and the joint component 111 on the inlet side, and the engaging portion 114. It is sandwiched and fixed between the joint component 112 on the outlet side and the joint component 112 on the outlet side.

With reference to FIGS. 8 to 10, the housing 110 has a shape in which ring-shaped engaging portions 113 and 114 are attached to both ends of the tubular member. A pressure measurement port 140 is arranged between the engaging portion 113 and the engaging portion 114. A tubular pressure measuring port 140 communicates with the chamber 102 of the housing 110, and the pressure in the chamber 102 can be measured from the pressure measuring port 140.

With reference to FIGS. 11 to 13, a partition wall 111w is provided on the joint component 111 on the inlet side, and a through hole 111h is provided on the partition wall 111w. The joint component 111 on the inlet side and the blood chamber are communicated with each other by a through hole 111h. Similar partition walls and through holes are provided in the joint parts on the outlet side.

With reference to FIGS. 14 and 15, the flexible membrane 120 has a substantially cylindrical shape, through which blood flows. In this embodiment, the flexible film 120 has a cylindrical shape, but it does not necessarily have to be a cylinder, and may be a square cylinder. Further, it may be an elliptical cylinder.

Further, in this embodiment, the outer diameter and the inner diameter of the flexible film 120 are constant, but the outer diameter and the inner diameter do not necessarily have to be constant, and the outer diameter and the inner diameter may be non-uniform.

(Embodiment 2)
With reference to FIG. 18, in the second embodiment, the structure of the pressure measuring unit 100 is different from that of the first embodiment. The pressure measuring unit 100 of the first embodiment has the housing 110, whereas the pressure measuring unit 100 according to the second embodiment does not have the housing 110, and the flexible film 120 is exposed. This is the pressure detector.

In the pressure detection unit, if the inside of the flexible film 120 is negative pressure, the flexible film 120 is deformed inward, and if the inside of the flexible film 120 is positive pressure, the flexible film 120 is deformed outward. .. The form of the pressure detecting unit may be a form that detects only negative pressure such as a pillow.

In the first and second embodiments, the flexible film 120 preferably has a shore A hardness of 80 or less. The constituent materials are not particularly limited, and for example, various rubber materials such as natural rubber, butyl rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, and silicone rubber, polyurethane-based, polyester-based, polyamide-based, olefin-based, and styrene. Various thermoplastic elastomers such as systems, polyvinyl chloride, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, cross-linked ethylene-vinyl acetate copolymer and other polyolefin, polyethylene terephthalate and other polyester , Polyurethane, polyamide and other various resins, and these can be used alone or in any combination. The molding method is not particularly limited, and examples thereof include injection molding, extrusion molding, compression molding, and transfer molding, and an appropriate method is used. Silicone rubber is easy to manufacture for extrusion molding, and styrene-based elastomer is easy to manufacture for injection molding.

Further, although the example in which the flexible film 120 is cylindrical has been described, the flexible film 120 may be flat as in Patent Document 1.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and it is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 Blood inlet, 2 Detension measurement site, 3, 6, 12 pressure transducer, 4 Blood pump, 5 Pressure measurement site, 7a dialyzer blood inlet, 7b dialyzer blood outlet, 8 dialyzer, 9a dialysate outlet, 9b dialysate inlet, 10 dialysis machine body, 11 venous pressure measurement site, 13 blood outlet, 100 pressure measurement unit, 102 chamber, 110 housing, 111, 112 joint parts, 111a wire, 111h through hole, 111w partition wall, 113 , 114 Engagement, 120 Flexible Membrane, 140 Pressure Measurement Port, 210, 220 Blood Line, 240 Pressure Monitor Line, 241 Connector, 242 Clip, 281,28 Branch, 290 Bypass.

Claims (3)

A blood circuit having a pressure measuring unit connected to a pressure measuring device.
The pressure measuring unit includes a housing and a diaphragm provided in the housing.
Blood pressure can be measured by flowing blood into the housing so as to be adjacent to the diaphragm and displaces the diaphragm according to the pressure of the blood to change the gap between the diaphragm and the housing.
A bypass path is further provided in parallel with the diaphragm so as to allow blood to flow when the flow path in the housing is blocked, and the pressure measuring unit is provided in a negative pressure portion of the blood circuit. The diaphragm is provided in the blood line, from the first branch portion provided in the blood line on the upstream side of the diaphragm to the second branch portion provided in the blood line on the downstream side of the diaphragm. A blood circuit in which the bypass path is provided, and the bypass path from the first branch portion to the second branch portion is the negative pressure portion of the blood circuit, and blood always flows through the bypass path. A blood circuit having a pressure measuring unit connected to a pressure measuring device.
The pressure measuring unit includes a tubular housing and a non-cylindrical tubular diaphragm provided in the tubular housing with a gap formed between the housing and the housing.
Blood pressure can be measured by flowing blood into the cylinder of the diaphragm and expanding the diaphragm in response to the pressure of the blood to reduce the gap between the diaphragm and the housing.
A bypass path provided in parallel with the diaphragm is further provided so that blood flows when the flow path in the diaphragm is blocked, the pressure measuring unit is provided in a negative pressure portion of the blood circuit, and the diaphragm is blood. The bypass path is provided from the first branch portion provided on the line and provided on the blood line on the upstream side of the diaphragm to the second branch portion provided on the blood line on the downstream side of the diaphragm. A blood circuit in which the bypass path from the first branch portion to the second branch portion is a negative pressure portion of the blood circuit, and blood always flows through the bypass path. A blood circuit that has a pressure detector
The pressure detection unit is a flexible bag body and has a flexible bag body.
A bypass path provided in parallel with the pressure detection unit is further provided so that blood flows when the flow path in the pressure detection unit is blocked, and the pressure detection unit is provided in a negative pressure portion of the blood circuit. The pressure detection unit is provided in the blood line, and the first branch provided in the blood line on the upstream side of the pressure detection unit and the second branch provided in the blood line on the downstream side of the pressure detection unit. A blood circuit in which the bypass path is provided up to the portion, and the bypass path from the first branch portion to the second branch portion is the negative pressure portion of the blood circuit, and blood always flows through the bypass path.

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