DIALYSIS SYSTEM HAVING DISPOSABLE CASSETTE AND INTERFACE THEREFORE

• US 20090012457A1
• Filed: 07/05/2007
• Published: 01/08/2009
• Est. Priority Date: 07/05/2007
• Status: Active Grant

• Current Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Original Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Inventors: Childers, Robert W., Hopping, Peter A.
• Granted Patent: US 7,909,795 B2
• Time in Patent Office: Days
• US Class Current: 604/29
• CPC Class Codes: A61M 1/152 Details related to the interface between cassette and machine
• CPC Class Codes: A61M 1/1522 the interface being evacuated interfaces to enhance contact
• CPC Class Codes: A61M 1/154 with sensing means or components thereof
• CPC Class Codes: A61M 1/155 with treatment-fluid pumping means or components thereof
• CPC Class Codes: A61M 1/1561 at least one cassette surface or portion thereof being flexible, e.g. the cassette having a rigid base portion with preformed channels and being covered with a foil
• CPC Class Codes: A61M 1/1565 Details of valves
• CPC Class Codes: A61M 1/159 specially adapted for peritoneal dialysis
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/166 Heating for sterilisation A61M1/1686
• CPC Class Codes: A61M 1/28 Peritoneal dialysis ; Other peritoneal treatment, e.g. oxygenation
• CPC Class Codes: A61M 1/284 Continuous flow peritoneal dialysis [CFPD]
• CPC Class Codes: A61M 1/288 Priming priming in extracorporeal blood circuits A61M1/3643
• CPC Class Codes: A61M 1/341 by measuring the filtrate rate or volume
• CPC Class Codes: A61M 2205/122 using evacuated interfaces to enhance contact
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3324 PH measuring means
• CPC Class Codes: A61M 2205/3331 Pressure; Flow
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3368 : Temperature

Abstract

A medical fluid flow control system includes an interface including a first pump area, the first pump area of the interface including a pneumatic actuator port and a gasket seal port; and a membrane gasket including a second pump area for mating with the first pump area, the second pump area including a blind section which covers the pneumatic actuator port when the gasket is mated with the interface, the second pump area further including an aperture, the aperture sized and positioned to seal around the gasket seal port, allowing a negative pressure to be applied through the gasket seal port to a flexible sheet of a pumping cassette.

Claims

1. A medical fluid flow control system comprising:

an interface including a first pump area, the first pump area of the interface including a pneumatic actuator port and a gasket seal port; and

a membrane gasket including a second pump area for mating with the first pump area, the second pump area including a blind section which covers the pneumatic actuator port when the gasket is mated with the interface, the second pump area further including an aperture, the aperture sized and positioned to seal around the gasket seal port, allowing a negative pressure to be applied through the gasket seal port to a flexible sheet of a pumping cassette.

2. The medical fluid flow control system of claim 1, further including the pumping cassette, the pumping cassette defining a pump chamber, a pumping portion of the flexible sheet covering the pump chamber.

3. The medical flow control system of claim 2, which is configured to mate the pumping portion of the flexible sheet with the blind section of the second pump area, the blind section and the pumping portion of the flexible sheet flexing together to pull dialysis fluid in and push dialysis fluid out of the pump chamber of the pumping cassette.

4. The medical fluid flow control system of claim 2, the negative pressure applied through the gasket seal port sealing the pumping portion of the flexible sheet to the second pump area.

5. The medical fluid flow control system of claim 2, wherein the pump chamber of the cassette has a shape at least substantially similar to a shape of the second pump area, which is at least substantially similar to a shape of the first pump area.

6. The medical fluid flow control system of claim 1, wherein the first pump area includes at least one of a well and a raised ridge.

7. The medical fluid flow control system of claim 6, wherein at least one of:

(i) the pneumatic actuator port is a bore through the well, (ii) the gasket seal port resides adjacent to the well, and (iii) the blind section of the pump area of the gasket is sized to seal around the raised ridge of the first pump area.

8. The medical fluid flow control system of claim 1, wherein the gasket seal port projects from a base of the interface so as to be able to extend at least partially through the aperture in the membrane gasket.

9. The medical fluid flow control system of claim 1, which includes an additional pump area of the interface, which mates with an additional pump area of the gasket.

10. The medical fluid flow control system of claim 1, which includes a pressure sensor monitoring the negative pressure, and a logic implementor operable with an output of the pressure sensor to determine if a leak associated with one of the following has occurred (i) the second pump area and (ii) a portion of the flexible sheet of the pumping cassette mated with the second pump area.

11. The medical fluid flow control system of claim 10, which includes a fluid sensor, the logic implementor further configured to determine (i) that the leak is in the membrane gasket if the fluid sensor does not detect a fluid or (ii) that the leak is in the flexible sheet of the pumping cassette if the fluid sensor detects a fluid.

12. A medical fluid flow control system comprising:

an interface including a first valve area, the first valve area including a pneumatic actuator port and a gasket seal port; and

a membrane gasket including a second valve area for mating with the first valve area, the second valve area including a blind section which covers the pneumatic actuator port when the gasket is mated with the interface, the second valve area further including an aperture, the aperture sized and positioned to seal around the gasket seal port, allowing a negative pressure to be applied through the gasket seal port to a flexible sheet of a pumping cassette.

13. The medical fluid flow control system of claim 12, further including the pumping cassette, the pumping cassette defining a valve chamber, a valve portion of the flexible sheet covering the valve chamber.

14. The medical flow control system of claim 13, which is configured to mate the valve portion of the flexible sheet with the blind section of the second valve area, the blind section and the valve portion of the flexible sheet flexing together to open and close a fluid pathway of the pumping cassette.

15. The medical fluid flow control system of claim 13, the negative pressure applied through the gasket seal port sealing the valve portion of the flexible sheet to the second valve area.

16. The medical fluid flow control system of claim 13, wherein the valve chamber of the cassette has a shape at least substantially similar to a shape of the second valve area, which is at least substantially similar to a shape of the first valve area.

17. The medical fluid flow control system of claim 12, wherein the first valve area includes a raised seat, the pneumatic actuator port being a bore through the raised seat.

18. The medical fluid flow control system of claim 17, wherein the gasket seal port resides adjacent to the raised seat.

19. The medical fluid flow control system of claim 17, wherein the blind section of the second valve area is sized to seal around the raised seat of the first valve area.

20. The medical fluid flow control system of claim 12, which includes an additional valve area of the interface, which mates with an additional valve area of the gasket.

21. The medical fluid flow control system of claim 12, which includes a pressure sensor monitoring the negative pressure, and a logic implementor operable with an output of the pressure sensor to determine if a leak associated with one of the following has occurred (i) the second valve area and (ii) a portion of the flexible sheet of the pumping cassette mated with the second valve area.

22. The medical fluid flow control system of claim 21, which includes a fluid sensor, the logic implementor further configured to determine (i) that the leak is in the membrane gasket if the fluid sensor does not detect a fluid or (ii) that the leak is in the flexible sheet of the pumping cassette if the fluid sensor detects a fluid.

23. A medical fluid flow control system comprising:

an interface including a pump actuator port, a pump seal port, a valve actuator port and a valve seal port;

a membrane gasket including a pump actuation area, a pump aperture, a valve actuation area and a valve aperture;

a pumping cassette, the cassette defining a pump chamber and a valve chamber, a pump portion of a flexible sheet covering the valve chamber, and a valve portion of the flexible sheet covering the valve chamber;

wherein the pump seal port and valve seal port are operable with the pump and valve apertures to seal (i) the pump portion of the flexible sheet to the pump actuation area of the membrane gasket and (ii) the valve portion of the flexible sheet to the valve actuation area of the membrane gasket; and

wherein the pump actuator port and valve actuator port are configured to move (i) the pump portion of the flexible sheet and the pump actuation area of the membrane gasket at the pump chamber of the cassette and (ii) the valve portion of the flexible sheet and the valve actuation area of the membrane gasket at the valve chamber of the cassette.

24. The medical fluid flow control system of claim 23, wherein at least one of (i) the pump actuation area of the membrane gasket includes a blind section that covers the pump actuator port of the interface and (ii) the valve actuation area of the membrane gasket includes a blind section which covers the valve actuator port of the interface.

25. The medical fluid flow control system of claim 23, which includes a pressure sensor monitoring a negative pressure, and a logic implementor operable with an output of the pressure sensor to determine if a leak associated with one of the following has occurred (i) the pump actuation area of the membrane gasket and (ii) a portion of the flexible sheet of the pumping cassette mated with the pump actuation area of the membrane gasket;

(iii) the valve actuation area of the membrane gasket and (ii) a portion of the flexible sheet of the pumping cassette mated with the valve actuation area of the membrane gasket.