Enhanced clearance in an artificial kidney incorporating a pulsatile pump

Patent metadata

Field	Value
Publication number	US-9402941-B2
Application number	US-201414152276-A
Country	US
Kind code	B2
Filing date	Jan 10, 2014
Priority date	Nov 16, 2001
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

A continuous renal replacement therapy (CRRT) device is provided that weighs between 2 and 10 pounds. The CRRT device can be portable, mobile or completely worn on the person of the patient. Blood and dialysate are each pumped in a pulsed or pulsatile manner through a dialyzer such that a significant portion of the peak pulse of the blood flow coincides with a significant portion of a low pulse portion of the dialysate flow. An differential pressure between a dialysate inlet of the dialyzer and the blood inlet of the dialyzer periodically changes from a high differential pressure of between 70 and 120 mmHg for a first time period and a low differential pressure of between −10 and 10 mmHg for a first time period and a low differential pressure of between −10 and 10 mmHg for a second time period. The frequency of the high and low differential pressure cycle is between about 0.5 and 4 Hz.

First claim

What is claimed is:

1. A method of dialysis comprising:
receiving blood in a blood circuit of a dialysis device;
pumping the blood in a pulsed manner to provide an average pulsatile blood flow rate of between 30 and 90 ml/min;
pumping dialysate, in a dialysate circuit of said dialysis device, in a pulsed manner to provide an average pulsatile dialysate flow rate of between 30 and 90 ml/min;
receiving said pumped blood at a blood inlet of a dialyzer; and
receiving said pumped dialysate at a dialysate inlet of said dialyzer, wherein a pressure differential between said blood in said blood inlet and said dialysate in said dialysate inlet fluctuates at a periodic rate between 0 mmHg+/−10 mmHg and 120 mmHg+/−20 mmHg; and
transferring urea molecules from said blood to said dialysate while said blood and said dialysate are passing through said dialyzer;
cleaning said dialysate by a filtration means, said cleaned dialysate being recirculated in said dialysate circuit.

2. The method of claim 1 , wherein cleaning said dialysate further comprises regenerating said dialysate by adding predetermined additives to said dialysate.

3. The method of claim 1 , wherein said periodic rate is between 0.5 and 4 Hz.

4. The method of claim 1 , wherein said method is provided by at least one of a completely wearable and a portable dialysis device.

5. The method of claim 1 , wherein said pumping of said blood further comprises pumping of said blood by a first channel of a dual channel pulsatile pump and said pumping of said dialysate further comprises pumping of said dialysate by a second channel of said dual channel pulsatile pump.

6. The method of claim 1 , wherein said dual channel pulsatile pump pumps said blood and pumps said dialysate such that a peak flow of said blood occurs in an alternating pattern with a peak flow of said dialysate.

7. The method of claim 1 , wherein said pumping said blood in a pulsed manner comprises providing in an alternating manner a high blood flow rate portion and a low blood flow portion, and wherein said pumping dialysate in a pulsed manner comprises providing in an alternating manner a high dialysate flow rate portion and a low dialysate flow rate portion, said high blood flow rate portion and said low dialysate flow rate portion each occurring, at least for a majority of their durations, at the same time.

Assignees

• Fresenius Medical Care Holdings Inc

Inventors

• Rambod Edmond
• Gura Victor

Classifications

• A61M2205/3324

  PH measuring means · CPC title

• A61M2205/15

  Detection of leaks · CPC title

• A61M2205/8206

  battery-operated · CPC title

• B01D2311/14

  Pressure control · CPC title

• A61M1/1617

  using measurements made during a temporary variation of a characteristic of the fresh dialysis fluid · CPC title