Systems and methods for performing hemodialysis

Patent metadata

Field	Value
Publication number	US-9757504-B2
Application number	US-201514594306-A
Country	US
Kind code	B2
Filing date	Jan 12, 2015
Priority date	Oct 31, 2008
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

Systems and methods for performing hemodialysis to remove metabolic waste from the blood of a patient are disclosed. The systems and methods preferably comprise at least one blood processing apparatus that receives whole blood from a patient. Cellular blood components are removed from the whole blood by hemofiltration, to provide filtered plasma comprising metabolic waste that is substantially reduced of blood cells. The cellular blood components may be returned to the patient. The filtered plasma comprising waste may be removed from the blood processing apparatus through a waste path for further processing in a separate apparatus, or in the same apparatus in a second stage processing procedure to remove metabolic waste components and excess water from the plasma by hemodialysis. At least one of the hemofiltration and hemodialysis processing apparatus comprises a Taylor vortex-enhanced separation apparatus.

First claim

The invention claimed is:

1. A blood processing system for performing hemodialysis on a patient to remove metabolic waste from the patient's blood comprising:
a blood processing apparatus having a first stage device and a second stage device downstream from the first stage device,
a first flow path for fluid communication from the patient to said first stage device of the blood processing apparatus,
said first stage device of the blood processing apparatus comprising:
spaced apart first inner and first outer surfaces defining a first gap therebetween, the flow path communicating with the first gap for flowing blood therethrough;
at least one of the first inner and first outer surfaces carrying a filter membrane,
a first drive assembly for causing relative movement between the first inner and first outer surfaces to create movement of the blood within the first gap that induces transport of plasma comprising waste through the membrane while substantially preventing the passage of blood cells therethrough to provide filtered plasma comprising waste that is substantially reduced of blood cells,

said second stage device of the blood processing apparatus comprising:
a second inner surface and a second outer surface spaced apart to define a second gap,
at least one of the second inner and second outer surfaces carrying a diffusion membrane having a facing side and an opposite side,
a passageway in communication with the opposite side of the diffusion membrane for conveying a solution along the opposite side of the diffusion membrane;
a second drive assembly causing relative movement between the second inner and outer surfaces to create movement of plasma comprising waste within the second gap that induces transport of waste comprising small molecules and medium molecules by diffusion from the facing side of the diffusion membrane to the solution conveyed along the opposite side of the diffusion membrane while the passage of said plasma comprising large molecules from the facing side of the diffusion membrane to the opposite side of the diffusion membrane is substantially prevented, and

a second flow path for fluidly communicating the plasma comprising large molecules from the facing side of the diffusion membrane back to the patient.

2. The blood processing system of claim 1 further comprising an access device for withdrawing and returning blood, blood cells and plasma to and from a patient.

3. The blood processing system of claim 1 further comprising a source of anti-coagulant in communication with said flow path between the patient and said blood processing apparatus.

4. The blood processing system of claim 1 further comprising a third flow path for fluid communication between said blood processing apparatus and said patient for conveying blood cells from said first stage device for return to the patient.

5. The blood processing system of claim 4 further comprising a fourth flow path for fluid communication with said blood processing apparatus for conveying waste from said apparatus.

6. The blood processing system of claim 1 wherein said filter membrane comprises at least one of a microporous membrane and a fibrous membrane.

7. The blood processing system of claim 6 wherein said filter membrane has a pore size sufficiently small to prevent the passage of red blood cells, platelets and white blood cells.

8. The blood processing system of claim 1 wherein said diffusion membrane blocks the passage of molecules having a molecular weight substantially greater than about 60,000 Daltons.

9. The blood processing system of claim 1 wherein said first and/or second drive assembly causes relative movement between the first inner and first outer surfaces and/or between the second inner and second outer surfaces at a selected surface velocity to create at least one of Couette flow and Taylor vortices therebetween.

Assignees

• Baxter Int
• Baxter Healthcare Sa

Inventors

• Watkins Randolph H
• Wurgler Steven J
• Maliekkal Shincy
• Karoor Sujatha
• Smith Katrina

Classifications

• A61M1/3479

  by dialysing the filtrate · CPC title

• B01D63/16 Primary

  Rotary, reciprocated or vibrated modules · CPC title

• B01D2315/02

  Rotation or turning · CPC title

• A61M1/3472

  with treatment of the filtrate · CPC title

• A61M1/26

  {and internal elements} which are moving · CPC title