Device and method for extracorporeal blood treatment

• US 5,277,820 A
• Filed: 02/06/1992
• Issued: 01/11/1994
• Est. Priority Date: 02/06/1992
• Status: Expired due to Term

• Current Assignee: HemoCleanse Technologies LLC (HemoCleanse, Inc.)
• Original Assignee: HemoCleanse, Inc.
• Inventors: Ash, Stephen R.
• Primary Examiner(s): Dawson, Robert A.
• Assistant Examiner(s): KIM, SUN U
• Application Number:
  US07/832,080
• Time in Patent Office: 705 Days
• Field of Search: 210/645, 210/646, 210/647, 210/650, 210/651, 210/655, 210/660, 210/694, 210/929, 210/723, 210/728, 210/729, 210/749, 210/767, 210/805, 210/744, 210/104, 210/117, 210/136 , 210/195.2, 210/196, 210/205, 210/219, 210/257.1, 210/258, 210/321.6, 210/321.67, 210/321.68, 210/321.71, 210/321, 210/75, 210/321.84, 210/502.1, 604/4, 604/5, 604/6, 436/178, 422/101
• US Class Current: 210/646
• CPC Class Codes: A61M 1/1627 Dialyser of the inside perfusion type, i.e. blood flow inside hollow membrane fibres or tubes
• CPC Class Codes: A61M 1/1643 with weighing of fresh and used dialysis fluid
• CPC Class Codes: A61M 1/1649 with pulsatile dialysis fluid flow
• CPC Class Codes: A61M 1/1692 Detection of blood traces in dialysate
• CPC Class Codes: A61M 1/1696 with dialysate regeneration
• CPC Class Codes: A61M 1/26 and internal elements which are moving
• CPC Class Codes: A61M 1/267 used for pumping
• CPC Class Codes: A61M 1/30 Single needle dialysis ; Reciprocating systems, alternately withdrawing blood from and returning it to the patient, e.g. single-lumen-needle dialysis or single needle systems for hemofiltration or pheresis
• CPC Class Codes: A61M 1/304 Treatment chamber used as reservoir, e.g. centrifuge bowl or filter with movable membrane
• CPC Class Codes: A61M 1/308 Volume control, e.g. with open or flexible containers, by counting the number of pump revolutions, weighing
• CPC Class Codes: A61M 1/3417 using distinct filters for dialysis and ultra-filtration
• CPC Class Codes: A61M 1/3427 back through the membrane, e.g. by inverted trans-membrane pressure [TMP]
• CPC Class Codes: A61M 1/3434 with pre-dilution and post-dilution
• CPC Class Codes: A61M 1/3437 downstream of the filter, e.g. post-dilution with filtrate
• CPC Class Codes: A61M 1/3458 having electrolytes not present in the dialysate
• CPC Class Codes: A61M 1/3472 with treatment of the filtrate
• CPC Class Codes: A61M 1/3475 with filtrate treatment agent in the same enclosure as the membrane
• CPC Class Codes: A61M 1/3493 using treatment agents in suspension
• CPC Class Codes: A61M 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2205/7563 with means preventing clogging of filters
• CPC Class Codes: A61M 60/113 : in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/37 : Haemodialysis, haemofiltration or diafiltration
• CPC Class Codes: A61M 60/43 : using vacuum at the blood pump, e.g. to accelerate filling
• CPC Class Codes: A61M 60/562 : for making blood flow pulsatile in blood pumps that do not intrinsically create pulsatile flow
• CPC Class Codes: A61M 60/837 : Aspects of flexible displacement members, e.g. shapes or materials
• CPC Class Codes: A61M 60/849 : Disposable parts
• CPC Class Codes: B01D 2321/2083 : By reversing the flow
• CPC Class Codes: B01D 61/00 : Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor separation of gases or vapours by diffusion B01D53/22
• CPC Class Codes: B01D 61/145 : Ultrafiltration
• CPC Class Codes: B01D 61/243 : Dialysis
• CPC Class Codes: B01D 61/58 : Multistep processes
• CPC Class Codes: B01D 63/16 : Rotary, reciprocated or vibrated modules
• CPC Class Codes: B01D 65/08 : Prevention of membrane fouling or of concentration polarisation
• CPC Class Codes: Y10T 436/255 : including use of a solid sorbent, semipermeable membrane, or liquid extraction

Abstract

Disclosed are preferred devices and methods which provide extracorporeal treatment of blood to effectively and consistently remove toxins therefrom and from patients over extended periods of time.

Claims

1. A method for extracorporeal treatment of blood to effectively and consistently remove toxins therefrom over an extended period of time, comprising:

passing the blood through a blood side of a plate dialyzer having a blood inlet to and a blood outlet from a blood side separated from a dialysate side by dialyzer membranes, said plate dialyzer further having a dialysate inlet to and dialysate outlet from said dialysate side, said dialyzer membranes being compliantly formed to expand and compress in response to alternating negative pressure and positive pressure on said dialysate side of said dialyzer; and

passing a sorbent suspension through said dialysate side so as to dialyze toxins in the blood across the membranes;

wherein said passing steps are caused by the application of alternating negative and positive pressure on said dialysate side so as to expand and contract said membranes and agitate the sorbent suspension to prevent settling and maintain chemical gradients across the membrane, while also maintaining a positive pressure gradient from said blood side to said dialysate side; and

wherein said alternating negative and positive pressure are caused by an accumulator reservoir connected to said dialysate side and operable to alternatively accumulate and expel dialysate.

2. The method of claim 1 wherein the sorbent suspension is an aqueous suspension including powdered activated charcoal.

3. The method of claim 2 wherein the charcoal has an average particle diameter of less than about 75 microns.

4. The method of claim 3 wherein said treatment is of blood of a patient having hepatic failure.

5. The method of claim 3 wherein said treatment is of blood of a drug overdose patient.

6. The method of claim 3 and also including the step of:

administering a dose of therapeutic agent to a patient;

and wherein said treatment is of blood of said patient following said administering and is effective to remove said thereapeutic agent.

7. The method of claim 3 wherein the sorbent suspension also comprises a cation exchanger.

8. The method of claim 7 wherein the sorbent suspension also comprises polyvinylpyrrolidone and a polyol flow inducing agent.

9. The method of claim 7 wherein said treatment is of blood of a patient having hepatic failure.

10. The method of claim 7 wherein said treatment is of blood of a drug overdose patient.

11. The method of claim 3 wherein the sorbent suspension also comprises polyvinylpyrrolidone and a polyol flow inducing agent.

12. The method of claim 11 wherein said treatment is of blood of a patient having hepatic failure.

13. The method of claim 11 wherein said treatment is of blood of a drug overdose patient.

14. A dialysis instrument, comprising:

a plate dialyzer having a blood inlet to and a blood outlet from a blood side separated from a dialysate side by dialyzer membranes, said plate dialyzer further having a dialysate inlet to and dialysate outlet from said dialysate side, said dialyzer membranes being compliantly formed to expand and compress in response to alternating negative pressure and positive pressure on said dialysate side of said dialyzer;

dialysate circulating means for circulating dialysate through said dialysate side of said dialyzer in a direction generally from said dialysate inlet to said dialysate outlet;

said dialysate circulating means including an accumulator reservoir operable to alternately accumulate and expel dialysate to apply alternating negative pressure and positive pressure on said dialysate side of said dialyzer and to thereby cause said expansion and contraction of dialyzer membranes while maintaining a positive pressure gradient from said blood side to said dialysate side of said dialyzer;

blood circulating means for circulating blood through said blood side of said dialyzer in a direction generally from said blood inlet to said blood outlet and powered by said expansion and contraction of dialyzer membranes caused by alternating negative and positive pressure on said dialysate side of said dialyzer.

15. The dialysis instrument of claim 14 which includes:

a dialysate storage reservoir;

first conduit means for fluidly connecting said dialysate reservoir to said dialysate inlet of said dialyzer;

second conduit means for fluidly connecting said dialysate reservoir to said dialysate outlet of said dialyzer;

a one-way valve in said second conduit means which allows flow only toward said dialysate storage reservoir;

and wherein said accumulator reservoir is fluidly connected to said second conduit means between said one-way valve and said dialysate outlet of said dialyzer so that dialysate expelled from said accumulating reservoir passes partially back into said dialysate side of said dialyzer and partially to said storage reservoir.

16. The dialysis instrument of claim 15 wherein said dialysate storage reservoir contains materials that are in a dry state, but which will form a dialysate sorbent suspension upon the addition of water.

17. The dialysis instrument of claim 14 wherein said dialysate circulating means includes a dialysate storage reservoir coupled to the dialysate inlet;

and

wherein said accumulator reservoir is connected between said dialysate outlet and said dialysate storage reservoir.

18. The dialysis instrument of claim 17 wherein a one way valve allowing dialysate flow toward said dialysate storage reservoir is located between said dialysate accumulating reservoir and said dialysate storage reservoir so that dialysate expelled from said accumulating reservoir passes partially into said dialysate side of said dialyzer and partially to said storage reservoir.

19. The dialysis instrument of claim 18 wherein said accumulator reservoir comprises a container having a port located above the maximum level to which dialysate accumulates in said container, through which negative and positive pressure can be alternately applied to cause said accumulation and expellation of dialysate into and from said container.

20. The dialysis instrument of claim 19 and also including means for alternately applying positive and negative pressure to said port.

21. The dialysis instrument of claim 20 which is adapted to cause counter-current flow of said dialysate and said blood.