Systems and methods for priming hemodialysis using dialysis fluid

1. A method for priming a hemodialysis treatment comprising:

providing a disposable cassette including at least a portion of a dialysate circuit and at least a portion of a blood circuit;

placing a dialyzer in fluid communication with the dialysate circuit via a to-dialyzer dialysate line and a from-dialyzer dialysate line;

placing the dialyzer in fluid communication with the blood circuit via an arterial blood line and a venous blood line;

placing a source of dialysis fluid in fluid communication with the dialyzer;

priming the dialysate circuit with dialysis fluid from the source while both the to-dialyzer dialysate line and the from-dialyzer dialysate line are connected at their dialyzer ends to the dialyzer; and

priming the blood circuit with dialysis fluid from the source by actuating at least one valve provided by the disposable cassette.

2. The method of claim 1 , wherein priming the blood circuit includes reversing a blood pump at least one time.

3. The method of claim 2 , which includes reversing the blood pump after a drip chamber is filled with fluid.

4. The method of claim 1 , wherein priming the blood circuit includes connecting patient ends of the arterial blood line and the venous blood line together.

5. The method of claim 1 , which includes actuating at least one valve in the blood circuit to prime the blood circuit.

6. The method of claim 1 , wherein priming the blood circuit includes directing the dialysis fluid at one time in a first direction away from the dialyzer and at another time in a second direction towards the dialyzer.

7. The method of claim 1 , wherein priming the blood circuit includes directing the dialysis fluid at one time in a treatment operation direction and at another time in a reverse of the treatment operation direction.

8. The method of claim 1 , wherein priming the blood circuit includes pumping the dialysis fluid through the dialyzer.

9. A dialysis machine configured and arranged to perform the method of claim 1 .

10. A method for priming a hemodialysis treatment comprising:

providing a sorbent cartridge for cleaning used dialysis fluid returning from a dialyzer;

preparing a batch of dialysis fluid in a quantity commensurate with being recycled through the sorbent cartridge multiple times;

priming a dialysate circuit in fluid communication with the dialyzer using the batch of dialysis fluid, while both a to-dialyzer dialysate line and a from-dialyzer dialysate line are connected at their dialyzer ends to the dialyzer; and

priming a blood circuit in fluid communication with the dialyzer using the batch of dialysis fluid.

11. The method of claim 10 , wherein preparing the batch of dialysis fluid includes mixing water and concentrate.

12. The method of claim 10 , wherein priming the blood circuit includes pumping dialysis fluid from the batch of dialysis fluid through the dialyzer.

13. The method of claim 10 , wherein priming the blood circuit includes connecting patient ends of an arterial blood line connected to the blood circuit and a venous blood line connected to the blood circuit together.

14. A dialysis machine configured and arranged to perform the method of claim 10 .

15. A dialysis system comprising:

a dialyzer;

a disposable cassette including at least a portion of a dialysate circuit and at least a portion of a blood circuit, the dialysate circuit in fluid communication with the dialyzer via a to-dialyzer dialysate line and a from-dialyzer dialysate line, the blood circuit in fluid communication with the dialyzer via an arterial blood line and a venous blood line;

a source of dialysis fluid in fluid communication with the dialyzer;

at least one dialysis fluid pump configured to pump dialysis fluid from the source of dialysis fluid through the dialysate circuit;

at least one blood pump configured to pump blood from a patient through the blood circuit; and

at least one processor configured to operate a sequence in which (i) the dialysate circuit is primed with dialysis fluid from the source of dialysis fluid while both the to-dialyzer dialysate line and the from-dialyzer dialysate line are connected at their dialyzer ends to the dialyzer; and

(ii) the blood circuit is primed with dialysis fluid from the source of dialysis fluid by actuating at least one valve provided by the disposable cassette.

16. The dialysis system of claim 15 , wherein the source of dialysis fluid includes regenerated dialysis fluid from a sorbent cartridge.

17. The dialysis system of claim 15 , wherein the at least one processor reverses the at least one blood pump at least one time to prime the blood circuit.

18. The dialysis system of claim 15 , wherein the at least one valve is located in the portion of the blood circuit included in the disposable cassette.

19. The dialysis system of claim 15 , wherein the at least one valve is in fluid communication with the arterial blood line.

20. The dialysis system of claim 15 , wherein the at least one processor is configured to prime the blood circuit with patient ends of the arterial blood line and the venous blood line connected together.