DEVICE, METHOD AND USE FOR TRANSFUSING BODY FLUIDS

Abstract

The invention concerns a device for the transfusion of body fluid, comprising a chamber for accommodating the body fluid, wherein the chamber has a cylindrical section and narrows in its end region, wherein the inclination of the wall in the end region of the chamber is continuous along the longitudinal axis.

Claims

1. A device (1) for the transfusion of body fluid, comprising a chamber (2) for accommodating the body fluid, wherein the chamber (2) has a cylindrical section (5) and narrows in its end region (6), wherein the inclination of the wall (8) in the end region of the chamber (2) is continuous along the longitudinal axis (7).

2. The device (1) as claimed in claim 1, wherein a fluid volume in the chamber (2), with a base area which corresponds to a base of the cylindrical section, undergoes at least a 1.5 to 2.0-fold extension along the longitudinal axis (7) of the chamber (2) in the end region (6) compared with a fluid volume in the cylindrical section (5).

3. The device (1) as claimed in claim 1 or claim 2, characterized in that at least in sections in the end region (6), the profile of the wall (8) of the chamber (2) is non-linear.

4. The device (1) as claimed in one of claims 1 to 3, characterized in that the end region (6) has an extent along the longitudinal axis (7) of the chamber (2) in the range from 15 mm to 40 mm and/or the cylindrical section (5) has an extent along the longitudinal axis (7) of the chamber (2) in the range from 38 mm to 63 mm.

5. The device (1) as claimed in one of claims 1 to 4, wherein the wall (8) in the end region (6) has (a) an exponential, (b) a polynomially shaped or (c) a hyperbolic profile.

6. The device (1) as claimed in one of claims 1 to 5, wherein the chamber (2) has a rigid wall (8).

7. The device (1) as claimed in one of claims 1 to 6, wherein an opening (3) is provided in the end region (6) of the chamber (2) and a connection piece (4) is provided at the opening (3) outside the chamber (2).

8. The device (1) as claimed in claim 7, wherein the connection piece (4) is configured as part of (a) a screw connection, (b) a Luer or Luer lock connection, (c) a bayonet connection and/or (d) a push connection.

9. The device (1) as claimed in one of claims 1 to 8, wherein the wall (8) of the chamber (2) is optically transparent in configuration, at least in a section of the end region (6).

10. The device (1) as claimed in one of claims 1 to 9, wherein the chamber (2) has a volume in the range from 5 to 50 ml.

11. A method for transfusing body fluid, comprising a chamber, wherein the body fluid is accommodated in the chamber, wherein the chamber has a cylindrical section and narrows in an end region, and wherein the inclination of the wall of the chamber in the end region is continuous along the longitudinal axis.

12. Use of a chamber during transfusion of a body fluid, wherein the chamber is used to accommodate the body fluid, wherein the chamber has a cylindrical section and narrows in its end region, and wherein the inclination of the wall in the end region of the chamber is continuous along the longitudinal axis.

Description

[0036] The invention will now be described in more detail with the aid of the drawings, which illustrate an embodiment of the invention. In the drawings:

[0037] FIG. 1: shows a diagrammatic view of a device containing blood prior to centrifugation;

[0038] FIG. 2: shows a device in accordance with FIG. 1 following centrifugation;

[0039] FIG. 3: shows the device in accordance with FIG. 2 after transfusing a portion of the body fluid from the chamber;

[0040] FIG. 4: shows a profile of a wall along a longitudinal axis; and

[0041] FIG. 5: shows a further embodiment.

[0042] FIG. 1 shows a diagrammatic view of a device 1 containing blood. The device 1 has a chamber 2 for accommodating the blood. The device also has an opening 3 which is at the top in FIG. 1. By means of the opening 3, blood can be aspirated into the chamber 2 or can be discharged from the chamber 2. At the end of the device 1 adjacent to the opening 3 is a connection piece 4 which is formed as one piece with the device 1. In the case shown, the connection piece 4 is in the form of a Luer lock connection element.

[0043] The chamber 2 has a cylindrical section 5 and an end region which directly adjoins the cylindrical section 5, by means of which the cross section of the chamber narrows in the direction of the opening 3.

[0044] In the embodiment shown in FIG. 1, the cylindrical section 5 is configured as a straight circular cylinder and the chamber 2 is rotationally symmetrical in configuration. It is axially symmetrical and rotationally symmetrical with respect to the longitudinal axis 7. The wall of the chamber 2 is linear in the cylindrical section 5, and in the transition to the end region 6 as well as in the end region 6 itself, it is continuous without any steps. By considering the distance between the wall 8 of the chamber 2 and the longitudinal axis 7 as a function over the longitudinal axis 7 (see FIG. 4), the absence of steps in the profile of the wall 8 can then be described by stating that the inclination or slope of the function is continuous over the longitudinal axis 7.

[0045] Furthermore, the device 1 has a plate 9 which essentially has the dimensions of the base of the cylindrical section 5. The plate 9 is configured as a part of a plunger 10 with a rod 11. By moving the plate 9, the effective volume in the chamber 2 can be reduced or increased. As an example, the plate 9 may be drawn away from the opening 3 and blood can be aspirated into the chamber 2. In the exemplary embodiment shown in FIG. 1, the rod 11 may be separate from the plate 9 in order to allow for easy processing of the device 1 in a centrifuge. The longitudinal extent of the device 1 can be reduced by removing the rod 11 from the plate 9.

[0046] FIG. 2 shows the situation following centrifugation of whole blood. The upper layer or phase is the plasma and the lower layer has the erythrocytes. Between the plasma and the erythrocytes is what is known as the buffy coat, a thin layer formed from leukocytes and thrombocytes.

[0047] FIG. 3 shows the situation following movement of the plate 9 towards the opening 3 and a portion of the plasma having been forced out or aspirated from the chamber 2. Because of the continuous transitions and the continuous profile of the cylindrical section 5 and of the transition between the cylindrical section 5 and the end region 6 and the continuous profile in the end region 6 itself, there is almost no disruption to the boundaries between the individual phases and the narrowing of the end region 6 means that the volume is stretched out so that, as can be seen in FIG. 3, the buffy coat is extended in length and the boundary between the buffy coat and erythrocytes remains as a boundary which is as sharp as possible.

[0048] In the example shown in FIG. 3, removal is possible by means of a 10 mL syringe which can accommodate the buffy coat.

[0049] FIG. 4 diagrammatically shows the wall 8 of the chamber 2 both in the cylindrical section 5 as well as in the end region 6, as a function over the longitudinal axis 7. The wall profile is continuous, and in particular the inclination of the function has a continuous profile, whereupon a function is described thereby which does not have any steps and in particular does not have any discontinuities which could lead to a disruption of the boundary.

[0050] FIG. 5 diagrammatically shows a further embodiment of a device which is similar to the previously described embodiment of the device, but there is no rotational symmetry of the wall with respect to the longitudinal axis 7 in the end region 6.