JP2006255261A - Blood treatment equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blood treatment equipment capable of preventing the blood from being accumulated in a blood port part. <P>SOLUTION: The peripheral height h in a blood port part 1 having a blood infusion opening 20 is made smaller than usual to make a specific shape in which the volume of the inside space 8 is enough small, and so the fluid speed of the blood toward the peripheral part 15a can be enhanced sufficiently in all directions, and the uneven blood flow in the blood port part 1 and the accumulated blood generated from it can be prevented during the blood treatment. Herewith, the blood treatment can proceed effectively, and the infusion blood can be prevented from remaining at an autotransfusion operation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a blood processing apparatus used for blood purification, hemodialysis or ultrafiltration.

  2. Description of the Related Art Conventionally, blood treatment apparatuses that purify blood and separate specific components in blood using a hollow fiber are known. As examples of this blood processing apparatus, hemodialyzers, plasma separators, artificial lungs and the like are widely used. As an example of such a blood treatment apparatus, the structure of a cylindrical hemodialyzer is shown in FIG.

  In FIG. 2, the blood port portion 30 on the inlet side is, for example, a flat cross section having a substantially disk-shaped inner surface facing the cylindrical portion 14 (blood inlet 20) provided at the upper portion and the hollow fiber bundle opening surface 5a. And a funnel-shaped space 8 formed therein, guiding the blood 10 introduced from the blood inlet 20 to the inner space of the hollow fiber 5 and isolating the inside of the apparatus from the outside. . The blood port portion 30a on the outlet side has the same configuration, and the blood 10a that has passed through the internal space of the hollow fiber 5 is collected and led out from the blood outlet 21. The fixing cap 2 prevents the blood port portion 30 (or 30a) from separating from the housing 3 and guides the blood 10 introduced into the blood port portion 30 to the internal space of the hollow fiber 5 without leaking outside. The blood port 30 (or 30a) is hollowed through the packing 12 so that the blood 10a that has passed through the inner space of the hollow fiber 5 is guided to the space in the blood port 30a without leaking to the outside. It is brought into close contact with the partition wall 6 for fixing the yarn bundle. The housing 3 has a cylindrical shape and is formed of a transparent and hard synthetic resin. The inner space 9 is filled with several thousand to 20,000 hollow fibers 5.

  Further, the housing 3 is provided with an inlet 4 and an outlet 4a for the dialysate 11. A large number of hollow fibers 5 are filled in the internal space 9 of the housing 3, and both ends thereof are liquid-tightly fixed by partition walls 6 having excellent blood compatibility, and the internal space of the hollow fibers 5 is the internal space 8 of the blood port portion 30. Communicated with. The partition wall 6 is generally made of polyurethane resin, but the partition wall 6 isolates the internal space 8 of the blood port portion 30 (or 30a) from the internal space 9 of the housing 3, and the blood port portion 30 (or 30a) The internal space 8 and the internal space 9 of the housing 3 are in contact with each other only through the wall membrane of the hollow fiber 5.

  The blood 10 to be introduced enters the internal space of the hollow fiber 5 via the internal space 8 of the blood port portion 30 on the inlet side, and harmful substances in the blood 10 are removed from the housing 3 via the wall membrane of the hollow fiber 5. The blood 10a that has been discharged and cleaned into the internal space 9 is returned to the body via the internal space 8 of the blood port portion 30a on the outlet side. On the other hand, harmful substances discharged into the internal space 9 of the housing 3 are selected by the dialysate 11 introduced from the inlet 4 and taken out to the outside via the outlet 4a.

  Here, conventionally, when blood stays in the peripheral portion of the internal space 8 due to blood turbulence in the blood port portion 30 on the blood inlet side, the distribution of blood into the hollow fiber bundle becomes uneven. As a result, there is a problem in that the speed of blood flowing in the hollow fiber bundle varies, and as a result, blood coagulation occurs. For this reason, the blood port portion having a specific shape is formed so that the blood introduced from the blood introduction port flows uniformly in the circumferential direction in the funnel-shaped space 8 so that the blood does not stay in the blood port portion. It is known to use (for example, patent document 1). In this conventional technique, as the blood introduced from the blood introduction port flows down the flow path that increases due to the inclined shape of the flat portion expanding, the flow velocity decreases rapidly, so that a uniform pressure distribution is obtained at the hollow fiber bundle opening end surface. And the flow of blood flowing from each hollow fiber opening end is made uniform.

In general, the blood processing apparatus is used with the blood port portion on the inlet side facing upward, so the blood circuit attached to the blood introduction port hangs down due to the weight of the blood itself and the blood. When blood passes, blood turbulence similarly occurs, and the blood stays at the peripheral edge of the blood port portion. If hemodialysis is performed in such a state, the opening or the inside of the hollow fiber bundle that opens near the staying portion is narrowed or blocked, reducing the efficiency of blood treatment, and returning blood with physiological saline at the end of hemodialysis Even if the operation is performed, a phenomenon called “residual blood” is caused, in which all blood in the blood processing apparatus cannot be returned to the patient. For this reason, it is known to use a blood port portion having a specific shape so that turbulent blood introduced from the blood introduction port flows uniformly without a difference in flow rate in the circumferential direction (for example, Patent Document 2).
JP-A-7-184994 JP 2000-126285 A

  However, the above-described prior art has a problem that it is not possible to sufficiently prevent the blood from staying at the peripheral edge of the blood port portion. As will be described later, this is still due to a lack of internal design in the conventional blood port portion.

  An object of the present invention is to provide a blood processing apparatus that solves the above-described problems and can prevent the retention of blood in the blood port portion.

The present inventors have completed the present invention based on the following findings.
FIG. 4 shows a state in which blood stays in the conventional blood port section 30. This retention of blood is based on the general idea that the space space of the peripheral portion of the blood port portion needs to be widened in order to increase the processing efficiency of the peripheral portion of the hollow fiber bundle. This is because the entire volume of the internal space of the part has increased. That is, since the total volume of the internal space of the blood port portion is large, the blood 10 introduced into the blood port portion 30 in FIG. 4 is dispersed on the wide inner wall and the flow that diffuses to the peripheral portion does not become sufficiently strong. A flow velocity difference is generated when spreading to the peripheral edge, and a circumferential flow B is formed from a portion where the flow spreading compared to the other direction is fast to a slow portion A, so that a stay C of blood 10 occurs. .

  For this reason, the present inventors can sufficiently enhance the flow rate to the peripheral part in all directions by making the internal space of the blood port part on the inlet side narrower than before and sufficiently reducing its volume. As a result, it has been found that the retention of blood can be prevented, and the present invention has been completed. This finding has been made in hemodialyzers, but is common to all blood treatments using a blood treatment apparatus.

That is, a blood processing apparatus according to one configuration of the present invention includes a cylindrical housing that contains a hollow fiber bundle having an open end, and a pair of blood port portions that are liquid-tightly fixed to both ends of the housing. The blood port portion includes a flat portion having a substantially disk-shaped inner surface facing the hollow fiber bundle opening surface, and a tube that protrudes outward from the center portion and serves as a blood inlet or a blood outlet. In the blood port portion having at least a blood introduction port, wherein the inner surface shape of the flat portion is the hollow fiber at the peripheral edge portion of the substantially disk-shaped inner surface. The inner surface of the port portion flat portion has a peripheral height h from the bundle opening surface of 0.1 mm or more and 1.1 mm or less, and gradually rises linearly or downwardly from the peripheral portion toward the central portion. That it is shaped to have And butterflies.
The housing can have a fixed cap portion as shown in FIG.

  According to this configuration, the peripheral height in the blood port portion having the blood introduction port (hereinafter sometimes referred to as the inlet-side blood port) is made smaller than in the prior art, and the volume of the space inside is sufficiently small. By adopting the specific shape, the blood flow rate to the peripheral portion can be sufficiently enhanced in all directions, so that it is possible to prevent the uneven flow of blood in the blood port portion and the occurrence of stagnation due to the blood treatment. . Thereby, blood processing can be performed efficiently and the residual blood phenomenon at the time of blood return operation can be prevented.

  Preferably, when the inner surface of the port portion flat portion in the inlet-side blood port is a linear slope, the inclination angle β of the inner surface of the port portion flat portion with respect to the hollow fiber bundle opening surface is 1 ° or more and 7 ° or less. More preferably, the peripheral height h is not less than 0.5 mm and not more than 1.0 mm, and the inclination angle β is not less than 3 ° and not more than 7 °.

  Preferably, when the inner surface of the port portion flat portion in the inlet-side blood port is gradually raised downward and convexly, the virtual parallel surface parallel to the hollow fiber bundle opening surface and passing through the peripheral edge upper end and the gradually raised surface L is the shortest distance on the virtual parallel plane from the intersection with the perpendicular line descending from the end point to the virtual parallel plane to the upper end of the peripheral edge, and t is the distance along the vertical line from the intersection point to the gradually rising end point. In this case, the inner surface of the port portion flat portion has a curved surface shape within a range of 1/17 <t / L <8/17.

In the blood processing apparatus of the present invention, it is preferable that the inclination θ of the inner wall of the cylindrical portion with respect to at least the central axis of the inlet-side blood port is 0.5 ° or more and 10 ° or less.
In the blood processing apparatus of the present invention, it is practically convenient for the outlet side blood port to have the same shape as the inlet side blood port, but the present invention is not necessarily limited thereto.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The blood processing apparatus according to the first embodiment of the present invention has substantially the same configuration as that shown in FIG. 2 except for the blood port portions 30 and 30a, and thus the description of the same portions will be omitted. In the present invention, the O-ring 17 (FIG. 1) is provided between the blood port portion 1 and the partition wall 6, but it may be replaced with packing or the like.

  FIG. 1 shows an enlarged view of a blood port portion 1 of a blood processing apparatus according to an embodiment of the present invention. In this figure, the blood port portion 1 on the inlet side is shown, but the blood port portion on the outlet side also has the same shape.

  The blood port portion 1 includes a flat portion 15 having a substantially disk-shaped inner surface 15b facing the hollow fiber bundle opening surface 5a, and a cylindrical portion that protrudes outward from the center portion and serves as a blood inlet 20 or a blood outlet 21. 14 and a funnel-shaped space 8 is formed therein.

  The substantially disk-shaped inner surface 15b of the flat portion 15 has a shape having an inner surface of the port portion flat portion of a slope that rises linearly from the upper end of the peripheral portion 15a toward the central portion. The peripheral height h from the hollow fiber bundle opening surface 5a to the upper end of the peripheral portion 15a in the peripheral portion 15a is not less than 0.1 mm and not more than 1.1 mm. The smaller the peripheral height h, the smaller the volume of the internal space 8 of the blood port portion 1, but the peripheral height h may be 0.5 mm or more and 1.0 mm or less in consideration of air bleedability at the peripheral portion 15a. More preferred.

  The inclination angle β of the port portion flat portion inner surface 15b with respect to the hollow fiber bundle opening surface 5a is preferably 1 ° or more and 7 ° or less. Although the volume of the internal space 8 of the blood port portion 1 is smaller as the inclination angle β is smaller, the inclination angle β is more preferably 3 ° or more and 7 ° or less considering the air escape property in the peripheral edge portion 15a. .

  Since the volume of the internal space 8 defined by the peripheral height h inside the blood port portion 1 and the inclination angle β of the port portion flat portion inner surface 15b with respect to the hollow fiber bundle opening surface 5a is sufficiently small as compared with the conventional case, Since the blood flow velocity to the peripheral edge portion 15a can be sufficiently enhanced in all directions, a flow (B) due to a flow velocity difference when spreading to the peripheral edge portion as shown in FIG. 4 is not formed, and therefore the peripheral edge portion 15a of the blood port portion 1 is formed. It is possible to prevent stagnation of blood.

  The inclination θ of the inner wall 20a of the blood inlet 20 with respect to the central axis O of the blood port portion 1, that is, the plane including the central axis of the blood inlet 20 with respect to the central axis of the blood inlet 20, and the blood inlet 20 The angle θ at which the virtual straight line formed by the intersection with the inner wall 20a inclines is preferably 0.5 ° or more and 10 ° or less. When the inclination θ is less than 0.5 °, mold release is difficult when the blood port portion 1 is molded by injection molding, and when it exceeds 10 °, the blood flow velocity decreases while passing through the blood introduction portion 20. The flow rate of the blood that has flowed into the peripheral portion 15a of the blood port portion 1 is formed in the circumferential direction in a portion that is slower than the others, and then the flow of the fast portion toward the center from the peripheral portion 15a. On the other hand, it tends to be difficult to speed up.

  In addition, in this blood port portion 1, the diameter of the inner surface of the blood port portion 1, that is, the distance (diameter) between the inner peripheral ends of the O-ring 17 is D, the inner wall 20a of the blood inlet 20 and the inner surface 15b of the port portion flat portion. R is the radius of curvature of a curved surface (a curve connecting the straight lines in the cross section) provided between the two.

  Thus, in the first embodiment, the blood port portion 1 on the inlet side flows in by making the peripheral height h smaller than the conventional one and making the volume of the internal space 8 sufficiently small. The flow velocity of blood to the peripheral edge portion 15a of the blood port portion 1 is sufficiently strengthened, and even in a slow portion as compared with others, after being formed in the circumferential direction, it is sufficiently faster than the flow from the peripheral portion 15a toward the center. Therefore, it is possible to prevent the occurrence of uneven flow inside the port during the blood treatment and the occurrence of stagnation. Thereby, blood processing can be performed efficiently and the residual blood phenomenon at the time of blood return operation can be prevented.

  FIG. 3 shows a second embodiment. The port portion flat portion inner surface 15b of the second embodiment is gradually raised downward in a convex shape, unlike the slope in which the first embodiment is linearly raised from the upper end of the peripheral edge portion 15a toward the center portion. Yes. Other configurations are the same as those of the first embodiment. In this case, a virtual parallel surface d parallel to the hollow fiber bundle opening surface 5a and passing through the upper end of the peripheral edge portion 15a, and a perpendicular e extending from the gradually rising end point (connection point of a straight line and a curve in the cross section) to the virtual parallel surface, L is the shortest distance on the virtual parallel plane d from the intersection point to the upper end of the peripheral edge 15a, and t is the distance along the perpendicular line e from the intersection point to the gradually rising end point. Is a curved surface shape preferably within a range of 1/17 <t / L <8/17, more preferably within a range of 3/17 <t / L <8/17. The curved surface shape of the port portion flat portion inner surface 15b is not particularly limited, and examples thereof include an ellipse shape, a parabola shape, a hyperbola shape, and the like in the shape of a cross section in a virtual plane including the central axis O.

  In the second embodiment, the volume of the internal space 8 defined by the peripheral height h inside the blood port portion 1 and the range of t / L of the port portion flat portion inner surface 15b that gradually rises downward in a convex shape. Since it can be made sufficiently small compared to the conventional case, the blood flow rate to the peripheral portion 15a can be sufficiently strengthened as in the first embodiment, so that the blood can be prevented from staying in the peripheral portion 15a. In addition, in the second embodiment, the volume of the internal space 8 can be made smaller than the first embodiment having a linear slope because the port portion flat portion inner surface 15b is convex downward. However, the air bleedability at the peripheral edge portion 15a of the second embodiment tends to be slightly lower than that of the first embodiment.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not restrict | limited at all by these Examples.
In each example, 40% glycerin aqueous solution (hereinafter referred to as glycerin solution) having a viscosity equal to that of blood is used as simulated blood. The glycerin solution was prepared by mixing 60% by weight of water and 40% by weight of purified glycerin (manufactured by Kao Corporation). When the viscosity of the glycerin solution was measured using a B-type viscometer (manufactured by Toki Kogyo Co., Ltd.) at 25 ° C., it was 3.2 centipoise (cP). This glycerin solution was previously colored with a pigment (T-600 RED-R, manufactured by Dainichi Seika Kogyo Co., Ltd.) so that the absorbance at 576 nm was 0.23 (using a spectrophotometer U-3210 Spectrophotometer manufactured by Hitachi, Ltd.) A glycerol solution diluted 300 times with water is measured) and an uncolored one is prepared.

  In the first embodiment, the port portion flat portion inner surface 15b of FIG. 1 is a straight slope, and its inclination angle β is 5 °, the peripheral height h is 1.0 mm, the inclination θ is 3.5 °, the diameter D is 39 mm, the radius R A transparent blood port made of polycarbonate with a thickness of 6 mm was used. Example 2 is the same as Example 1 except that θ is 11 °, and Example 3 is the same as Example 1 except that h is 0.7 mm. Example 4 is the same as Example 1 except that h is 0.3 mm. The fifth embodiment is the same as the first embodiment except that the inclination angle β is 9 °. Example 6 is an elliptical curved surface in which the port portion flat portion inner surface 15b of FIG. 3 gradually rises downward, and h is 0.7 mm, θ is 3.5 °, and D is 39 mm. In this ellipse, for example, the ratio between the lengths of the short axis and the long axis (t / L) is 6/17, and a downward convex 1/4 portion is used.

  In Comparative Example 1 (conventional product), the inner surface of the flat portion of the port portion is a straight slope, and its inclination angle β is 5 °, h is 1.5 mm, θ is 3.5 °, D is 39 mm, and R is 6 mm. In Comparative Example 2 (conventional product), the inclination angle β was 6.0 °, h was 4 mm, θ was 1.0 °, D was 38 mm, and R was 3 mm.

(Flow state observation)
The observation of the flow in the blood port portion is made by filling the colored glycerin solution into the blood port portion, introducing the uncolored glycerin solution at 200 ml / min, and visually checking the replacement of the colored glycerin and the uncolored glycerin. This was done by observing. The results are shown in Table 1.

  Further, in the present invention, there is a concern that the air bleedability at the peripheral portion is not sufficient because the space space at the peripheral portion of the blood port portion is reduced. Therefore, these evaluations were also performed below.

(Evaluation of air release)
In the hemodialyzer, the air bleed operation is performed after the water in the hemodialyzer is replaced with physiological saline before the start of hemodialysis. With respect to this air release property, the hemodialyzer was tilted in a state where an air reservoir was formed in the blood port portion, and the state where the air reservoir reached the peripheral portion was visually observed. For Examples 1 to 6 and Comparative Examples 1 and 2, this air release property was evaluated by the correlation between the degree of arrival at the peripheral edge of the blood port portion and the peripheral height h. The results are shown in Table 1.

  About Example 1, when the replacement | exchange of the colored glycerol solution and the uncolored glycerol solution was observed visually, the disorder | damage | failure of the flow of blood was not confirmed and the residence did not generate | occur | produce in the blood port part. Moreover, the air release property was also good.

  When Example 2 was visually observed in the same manner, since the inclination θ was 11 °, the blood flow was not disturbed and the retention in the blood port portion hardly occurred. Moreover, the air release property was also good. When Example 3 was visually observed in the same manner, the disturbance of blood flow was not confirmed, and no stagnation occurred in the blood port portion. Moreover, the air release property was also good. When Example 4 was visually observed in the same manner, no disturbance of blood flow was confirmed, and no stagnation occurred in the blood port portion. In addition, although air bleedability is slightly lowered, there is no practical problem because the air reservoir reaches the peripheral edge when vibration is applied. In Example 5, when visually observed in the same manner, disturbance of blood flow and formation of a retention portion were hardly observed. Moreover, the air release property was good.

  When Example 6 was visually observed in the same manner, the disturbance of blood flow was not confirmed, and no stagnation occurred in the blood port portion. In addition, although air bleedability is slightly reduced, there is no practical problem because the air reservoir slowly reaches the peripheral edge without applying vibration.

  In Comparative Example 1 (conventional product), the replacement of the colored glycerin solution and the uncolored glycerin solution was visually observed in the same manner as in Example 1. As a result, the blood flow was disturbed and the formation of the retention portion was observed to a considerable extent. It was. In Comparative Example 2 (conventional product), when visually observed in the same manner, the blood flow was disturbed, and the formation of the residence portion was observed to a considerable extent.

  In Table 1, when Example 1 in which the inner surface of the flat portion of the blood port portion is a linear slope is compared with Example 6 having a downwardly convex oval shape, Example 1 has better air release properties. there were. Although Example 6 can reduce the volume of the internal space of the blood port portion and can more sufficiently enhance the blood flow rate to the peripheral portion, Example 1 is the most effective from the overall evaluation of the flow improvement effect and air bleedability. Rated as preferred.

It is sectional drawing which shows the blood port part of the blood processing apparatus concerning 1st Embodiment of this invention. It is sectional drawing which shows an example of a blood processing apparatus. It is sectional drawing which shows the blood port part of the blood processing apparatus concerning 2nd Embodiment. It is a top view which shows the generation | occurrence | production state of the retention of the blood in the conventional blood port part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 30, 30a: Blood port part 2: Fixing cap 3: Housing 5: Hollow fiber 5a: Hollow fiber bundle opening surface 6: Partition wall 8: Inner space of the blood port part 9: Inner space 10 of a housing, 10a: Blood 15 : Flat part 15a: Peripheral part 15b: Port part flat part inner surface 20 (14): Blood inlet (cylinder part)
20a: Inner wall for blood extraction (inner wall of the cylinder part)
21 (14): Blood outlet (cylinder part)

Claims (5)

A blood processing apparatus comprising a cylindrical housing containing a hollow fiber bundle having an open end, and a pair of blood port portions fixed in a liquid-tight manner to both ends of the housing,
The blood port portion has a flat portion having a substantially disk-shaped inner surface facing the hollow fiber bundle opening surface, and a cylindrical portion that protrudes outward from the central portion and serves as a blood inlet or a blood outlet. A funnel-shaped space is formed in the interior,
At least in the blood port part having a blood inlet, the inner surface shape of the flat part is a peripheral height h of 0.1 mm or more from the hollow fiber bundle opening surface to the upper end of the peripheral part at the peripheral part of the substantially disk-shaped inner surface. The blood is 1.1 mm or less and is formed so as to have an inner surface of the flat portion of the port portion that gradually rises linearly or convexly downward from the upper end of the peripheral portion toward the central portion. Processing equipment. In claim 1,
A blood processing apparatus in which an inclination angle β of the inner surface of the port portion flat portion with respect to the hollow fiber bundle opening surface is 1 ° or more and 7 ° or less when the inner surface of the port portion flat portion is a linear slope. In claim 2,
The blood processing apparatus, wherein the peripheral height h is not less than 0.5 mm and not more than 1.0 mm, and the inclination angle β is not less than 3 ° and not more than 7 °. In claim 1,
When the inner surface of the flat portion of the port portion is gradually raised downward and convexly, a virtual parallel surface that passes through the upper end of the peripheral edge parallel to the hollow fiber bundle opening surface, and from the gradually rising end point to the virtual parallel surface When the shortest distance on the virtual parallel plane from the intersection with the lowered perpendicular to the upper edge of the peripheral edge is L, and the distance along the perpendicular from the intersection to the gradually rising end point is t, the port portion flat portion A blood processing apparatus, wherein the inner surface has a curved surface shape within a range of 1/17 <t / L <8/17. In any one of Claims 1-4,
A blood processing apparatus, wherein an inclination θ of an inner wall of the cylindrical portion with respect to a central axis of a blood port portion having at least a blood inlet is 0.5 ° or more and 10 ° or less.

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