Personal hemodialysis system

• US 8,114,276 B2
• Filed: 10/23/2008
• Issued: 02/14/2012
• Est. Priority Date: 10/24/2007
• 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., Kelly, Thomas D., Roger, Rodolfo
• Primary Examiner(s): Drodge, Joseph
• Application Number:
  US12/257,014
• Publication Number:
  US 20090107902A1
• Time in Patent Office: 1,209 Days
• Field of Search: 210/97, 210/134, 210/137, 210/258, 210/321.6, 210/321.71, 210645-647, 210/321.65, 604/4.01, 604/5.01, 604/6.01, 604/6.05, 604/6.09, 604/29, 604 65- 67, 417/474, 137/885
• US Class Current: 210/97
• CPC Class Codes: A61M 1/14 Dialysis systems; Artificial kidneys; Blood oxygenators semi-permeable membranes characterised by the material, manufacturing processes therefor B01D71/00; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
• CPC Class Codes: A61M 1/1524 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/153 the cassette being adapted for heating or cooling the treating fluid, e.g. the dialysate or the treating gas
• 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 1/15625 the reservoirs acting as balance chambers
• CPC Class Codes: A61M 1/1565 Details of valves
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1601 Control or regulation
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1621 Constructional aspects thereof semi-permeable membranes for separation processes characterised by their properties B01D69/00; semi permeable membranes characterised by their material B01D71/00
• CPC Class Codes: A61M 1/1635 with volume chamber balancing devices between used and fresh dialysis fluid
• CPC Class Codes: A61M 1/1649 with pulsatile dialysis fluid flow
• CPC Class Codes: A61M 1/166 Heating for sterilisation A61M1/1686
• CPC Class Codes: A61M 1/168 Sterilisation or cleaning before or after use
• CPC Class Codes: A61M 1/1686 by heat
• CPC Class Codes: A61M 1/1688 with recirculation of the sterilising fluid
• CPC Class Codes: A61M 1/28 Peritoneal dialysis ; Other peritoneal treatment, e.g. oxygenation
• CPC Class Codes: A61M 1/281 Instillation other than by gravity
• CPC Class Codes: A61M 1/3465 using dialysate as substitution fluid
• CPC Class Codes: A61M 1/362227 : the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/36225 : with blood pumping means or components thereof
• CPC Class Codes: A61M 1/362261 : 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 1/362262 : Details of incorporated reservoirs
• CPC Class Codes: A61M 1/362265 : Details of valves
• CPC Class Codes: A61M 1/3643 : Priming, rinsing before or after use
• CPC Class Codes: A61M 1/3644 : Mode of operation
• CPC Class Codes: A61M 1/3649 : using dialysate as priming or rinsing liquid
• CPC Class Codes: A61M 1/3652 : using gas, e.g. air
• CPC Class Codes: A61M 2205/128 : with incorporated valves
• CPC Class Codes: A61M 2205/14 : Detection of the presence or absence of a tube, a connector or a container in an apparatus
• CPC Class Codes: A61M 2205/3313 : used specific wavelengths
• CPC Class Codes: A61M 2205/3331 : Pressure; Flow
• CPC Class Codes: A61M 2205/3334 : Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3344 : Measuring or controlling pressure at the body treatment site
• CPC Class Codes: A61M 2205/3379 : Masses, volumes, levels of fluids in reservoirs, flow rates
• CPC Class Codes: A61M 2205/6036 : characterised by physical shape, e.g. array of activating switches
• CPC Class Codes: B01D 61/243 : Dialysis
• CPC Class Codes: B01D 61/244 : comprising multiple dialysis steps
• CPC Class Codes: B01D 61/30 : Accessories; Auxiliary operation
• CPC Class Codes: Y10T 137/0396 : Involving pressure control
• CPC Class Codes: Y10T 137/87893 : With fluid actuator
• CPC Class Codes: Y10T 29/49826 : Assembling or joining

Abstract

A dialysis machine includes a dialysis instrument having a pump actuator and first and second valve actuators, and a disposable cassette operable with the dialysis instrument, the disposable cassette including a pump portion operable with the pump actuator, first and second valve chambers operable with the first and second valve actuators, the first and second valve chambers communicating fluidly with each other, at least the first valve chamber communicating fluidly with a compliance chamber, the compliance chamber negating a first backpressure due to a pneumatic closing pressure used to close the first valve chamber to help to ensure the pneumatic pressure applied to the first valve chamber will close the first valve chamber against a second backpressure from an existing closure of the second valve chamber.

Claims

1. A dialysis machine comprising:

a dialysis instrument having at least one peristaltic pump actuator and first and second pneumatic valve actuators; and

a disposable cassette operable with the dialysis instrument, the disposable cassette including

a rigid portion, at least one pump tube extending from the rigid portion for operation with the at least one peristaltic pump actuator, the rigid portion defining first and second valve chambers in operable communication with the first and second valve actuators, respectively, the first and second valve chambers communicating fluidly with each other, at least the first valve chamber communicating fluidly with a compliance chamber, at least a portion of the compliance chamber being flexible for absorbing energy from a pneumatic closing pressure applied to close the first valve chamber, the compliance chamber positioned and arranged so that the absorbing of the energy tends to prevent the pneumatic closing pressure from opening an existing closure of the second valve chamber.

2. The dialysis machine of claim 1, which includes a flexible membrane sealed to the rigid portion, the pneumatic closing pressure applied to the membrane to close the first valve chamber.

3. The dialysis machine of claim 2, wherein the compliance chamber is formed in part via a portion of the flexible membrane, the flexible membrane portion configured to absorb the energy from the pneumatic closing pressure.

4. The dialysis machine of claim 2, which includes a flexible diaphragm located on an opposing side of the rigid portion from the flexible membrane, the compliance chamber formed in part via the flexible diaphragm, the flexible diaphragm configured to absorb the energy from the pneumatic closing pressure.

5. The dialysis machine of claim 1, which includes a flexible diaphragm located on an opposing side of the rigid portion from the first and second valve chambers, the flexible diaphragm configured to absorb the energy from the pneumatic closing pressure.

6. The dialysis machine of claim 1, the compliance chamber a first compliance chamber, and wherein the rigid portion defines third and fourth valve chambers, and which includes a second compliance chamber operating with the third and fourth valve chambers.

7. The dialysis machine of claim 1, the compliance chamber further configured to overcome a backpressure applied by the closing of the second valve chamber to the first valve chamber, to allow the first valve chamber to be closed.

8. The dialysis machine of claim 1, wherein the first valve chamber is located upstream of the second valve chamber.

9. The dialysis machine of claim 1, which includes a vacuum applied to the compliance chamber to absorb the energy from the pneumatic closing pressure applied to close the first valve chamber.

10. A dialysis machine comprising:

a dialysis instrument having a pump actuator and first and second valve actuators; and

a disposable cassette operable with the dialysis instrument, the disposable cassette including

a pump portion operable with the pump actuator,

first and second valve chambers operable with the first and second valve actuators, the first and second valve chambers communicating fluidly with each other, at least the first valve chamber communicating fluidly with a compliance chamber, wherein the compliance chamber is flexible and is positioned and arranged to negate a first backpressure due to a pneumatic closing pressure applied to close the first valve chamber to help to ensure the pneumatic pressure applied to the first valve chamber will close the first valve chamber against a second backpressure from an existing closure of the second valve chamber.

11. The dialysis machine of claim 10, wherein a pneumatic pressure applied to the second valve chamber is the same as the pneumatic pressure applied to the first valve chamber.

12. The dialysis machine of claim 10, wherein the compliance chamber is configured to prevent the first backpressure from existing around an outside of a port of the first valve chamber, the second backpressure existing inside the port.

13. The dialysis machine of claim 10, wherein the pump actuator is a peristaltic pump actuator and the cassette pumping portion is a tube operable with the peristaltic pump actuator.

14. The dialysis machine of claim 10, wherein the compliance chamber is further configured to tend to prevent the pneumatic pressure applied to the first valve chamber from opening the closed second valve chamber.

15. The dialysis machine of claim 10, which includes a vacuum applied to the compliance chamber to negate the first backpressure.

16. A dialysis machine comprising:

a dialysis instrument having a pump actuator and first and second valve actuators; and

a disposable cassette operable with the dialysis instrument, the disposable cassette including

a pump portion operable with the pump actuator,

first and second valve chambers operable with the first and second valve actuators, and

a compliance chamber in fluid communication with the first and second valve chambers, the compliance chamber defined at least in part by a rigid wall of the cassette and a diaphragm located on an opposing side of the rigid wall from the first and second valve chamber.

17. The dialysis machine of claim 16, wherein the rigid wall defines first and second apertures that allow the first and second valve chambers to communicate fluidly, respectively, with the compliance chamber.

18. The dialysis machine of claim 16, wherein the cassette includes a flexible membrane located on an opposing side of the cassette from the diaphragm, the membrane for closing the first and second valve chambers.

19. The dialysis machine of claim 16, the compliance chamber aiding at least one of:

(i) maintenance of an existing closure of the second valve chamber when the first valve chamber is closed; and

(ii) closure of the first valve chamber at a time when the second valve chamber is already closed.

20. The dialysis machine of claim 19, which includes a vacuum applied to the compliance chamber to provide said aiding.

21. A dialysis machine comprising:

a dialysis instrument having a pump actuator and first and second valve actuators; and

a disposable cassette operable with the dialysis instrument, the disposable cassette including

a rigid wall;

a flexible membrane;

a pump portion operable with the pump actuator,

first and second valve chambers operable with the first and second valve actuators, the first valve chamber extending from the rigid wall towards the flexible membrane and including a first aperture in the rigid wall, the second valve chamber extending from the rigid wall towards the flexible membrane and including a second aperture in the rigid wall, and

a compliance chamber defined in part by a portion of the flexible membrane used to close at least one of the first and second valve chambers, the compliance chamber including a third aperture formed in the rigid wall that is larger than the first and second apertures, the third aperture positioned to allow fluid flowing through the first and second valve apertures to communicate fluidly with the compliance chamber portion of the flexible membrane.

22. The dialysis machine of claim 21, wherein the compliance chamber further includes a rigid sidewall surrounding the third aperture and extending from the rigid wall towards the flexible membrane.

23. The dialysis machine of claim 21, the compliance chamber aiding at least one of:

(i) maintenance of an existing closure of the second valve chamber when the first valve chamber is closed; and

(ii) closure of the first valve chamber at a time when the second valve chamber is already closed.

24. The dialysis machine of claim 23, which includes a vacuum applied to the compliance chamber to provide said aiding.

25. A dialysis machine comprising:

a dialysis instrument having at least one pump actuator and first and second valve actuators; and

a disposable cassette operable with the dialysis instrument, the disposable cassette including

a rigid portion defining first and second valve chambers, the first and second valve chambers in operable communication with the first and second valve actuators, respectively, the first and second valve chambers communicating fluidly with each other, a flexible membrane located on a first side of the disposable cassette, wherein a closing pressure is applied to the flexible membrane to close the first valve chamber, at least the first valve chamber communicating fluidly with a compliance chamber, the compliance chamber formed at least in part by a flexible diaphragm located on an opposing second side of the disposable cassette, the flexible diaphragm configured to absorb the energy from the pneumatic closing pressure.

26. A dialysis machine comprising:

a dialysis instrument having at least one pump actuator and first, second, third and fourth valve actuators; and

a disposable cassette operable with the dialysis instrument, the disposable cassette including

a rigid portion defining first, second, third and fourth valve chambers in operable communication with the first, second, third and fourth valve actuators, respectively,

the first and second valve chambers communicating fluidly with each other, at least the first valve chamber communicating fluidly with a first compliance chamber, the first compliance chamber absorbing energy from a pneumatic closing pressure applied to close the first valve chamber and aiding at least one of;

(i) maintenance of an existing closure of the second valve chamber when the first valve chamber is closed, and (ii) closure of the first valve chamber at a time when the second valve chamber is already closed,

a flexible membrane sealed to the rigid portion, the pneumatic closing pressure applied to the membrane to close the first valve chamber, and

a second compliance chamber operating with the third and fourth valve chambers.

27. A dialysis machine comprising:

a dialysis instrument having at least one pump actuator and first and second pneumatic valve actuators;

a disposable cassette operable with the dialysis instrument, the disposable cassette including

a rigid portion defining first and second valve chambers, the first and second valve chambers in operable communication with the first and second valve actuators, respectively, the first and second valve chambers communicating fluidly with each other, at least the first valve chamber communicating fluidly with a compliance chamber formed in part by a flexible diaphragm located on an opposing second side of the disposable cassette, the flexible diaphragm configured to absorb energy from a pneumatic closing pressure applied to close the first valve chamber.