Balanced flow dialysis machine

• US 8,992,463 B2
• Filed: 02/19/2013
• Issued: 03/31/2015
• Est. Priority Date: 11/09/2007
• 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: Hogard, Michael E., Busby, Donald D., Childers, Robert W., Ding, Yuanpang Samuel, Holian, Katherine M., Jablonski, Mark E., Kelly, Thomas D., Lo, Ying-Cheng, Maliekkal, Shincy J., Roger, Rodolfo G., Smith, Donald A., Yardimci, Atif M.
• Primary Examiner(s): MEDWAY, SCOTT J
• Application Number:
  US13/770,662
• Publication Number:
  US 20130193073A1
• Time in Patent Office: 770 Days
• Field of Search: 604/118, 604/6.09, 604/5.01, 604/6.13, 604/4.01, 604/29, 604/67
• US Class Current: 604/29
• 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 1/1522 the interface being evacuated interfaces to enhance contact
• 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 1/154 with sensing means or components thereof
• 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 1/15632 the filter being a dialyser
• CPC Class Codes: A61M 1/1565 Details of valves
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1613 Profiling or modelling of patient or predicted treatment evolution or outcome
• CPC Class Codes: A61M 1/1635 with volume chamber balancing devices between used and fresh dialysis fluid
• CPC Class Codes: A61M 1/166 Heating for sterilisation A61M1/1686
• CPC Class Codes: A61M 1/1696 with dialysate regeneration
• CPC Class Codes: A61M 1/28 Peritoneal dialysis ; Other peritoneal treatment, e.g. oxygenation
• CPC Class Codes: A61M 1/284 Continuous flow peritoneal dialysis [CFPD]
• CPC Class Codes: A61M 1/288 Priming priming in extracorporeal blood circuits A61M1/3643
• CPC Class Codes: A61M 1/3401 Cassettes therefor
• CPC Class Codes: A61M 1/341 by measuring the filtrate rate or volume
• CPC Class Codes: A61M 1/3413 : Diafiltration
• CPC Class Codes: A61M 1/3417 : using distinct filters for dialysis and ultra-filtration
• CPC Class Codes: A61M 1/342 : Adding solutions to the blood, e.g. substitution solutions for preventing coagulation A61M1/3672
• 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 1/3441 : Substitution rate control as a function of the ultrafiltration rate
• CPC Class Codes: A61M 1/3444 : in which the collected ultra-filtrate expels an equal volume of substitution fluid from a reservoir
• CPC Class Codes: A61M 1/3458 : having electrolytes not present in the dialysate
• CPC Class Codes: A61M 1/3465 : using dialysate as substitution fluid
• CPC Class Codes: A61M 1/3468 : using treated filtrate as substitution fluid
• CPC Class Codes: A61M 1/362223 : the interface being evacuated interfaces to enhance contact
• CPC Class Codes: A61M 1/36224 : with sensing 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 1/362264 : the filter being a blood filter
• CPC Class Codes: A61M 1/362265 : Details of valves
• CPC Class Codes: A61M 2205/12 : with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2205/3331 : Pressure; Flow
• CPC Class Codes: A61M 2205/3334 : Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3368 : Temperature
• CPC Class Codes: A61M 2205/3393 : by weighing the reservoir

Abstract

A system and method for balancing flows of renal replacement fluid is disclosed. The method uses pressure controls and pressure sensing devices to more precisely meter and balance the flow of fresh dialysate and spent dialysate. The balancing system may use one or two balancing devices, such as a balance tube, a tortuous path, or a balance chamber.

Claims

1. A renal therapy system comprising:

a dialyzer;

a balancing system configured to equalize flow volume of renal failure therapy fluid flowing to the dialyzer and from the dialyzer, the balancing system including a fresh renal therapy fluid portion and a spent renal therapy fluid portion;

a fresh renal therapy fluid pressure sensor positioned and arranged to detect a pressure of fresh renal failure therapy fluid delivered to the fresh renal therapy fluid portion of the balancing system;

a spent renal therapy fluid pressure sensor positioned and arranged to detect a pressure of spent renal failure therapy fluid delivered to the spent renal therapy fluid portion of the balancing system; and

a controller configured to (i) receive signals from the fresh and spent renal therapy fluid pressure sensors indicative of the detected pressures of the fresh and spent renal failure therapy fluids, respectively, and (ii) use the signals to control the fresh renal therapy fluid and the spent renal therapy fluid for the balancing system so that a pressure of the fresh renal failure therapy fluid flowing to the balancing system is equal to a pressure of the spent renal failure therapy fluid flowing to the balancing system.

2. The renal therapy system of claim 1, which includes a cassette, the cassette including the balancing system.

3. The renal therapy system of claim 1, wherein the fresh renal therapy fluid pressure sensor and the spent renal therapy fluid pressure sensor sense pressure in fluid conduits communicating with the fresh renal therapy fluid portion and the spent renal therapy fluid portion, respectively.

4. The renal therapy system of claim 1, wherein the controller operates a plurality of valves to control the fresh and spent renal therapy fluid flow.

5. The renal therapy system of claim 1, wherein the balancing system includes at least one fresh and spent rigid chamber and a member that is moved back and forth within the rigid chamber by the fresh and spent renal therapy fluids.

6. A renal therapy method comprising:

providing a balancing system that equalizes flow volume of renal failure therapy fluid to a dialyzer and from the dialyzer;

detecting a pressure of fresh renal failure therapy fluid delivered to or from the balancing system;

detecting a pressure of spent renal failure therapy fluid delivered to or from the balancing system; and

electronically controlling the flow of fresh renal therapy fluid and the flow of spent renal therapy fluid for the balancing system such that the pressure of at least one of (i) the fresh renal failure therapy fluid flowing to the balancing system is equal to the pressure of the spent renal failure therapy fluid flowing to the balancing system, or (ii) the fresh renal failure therapy fluid flowing from the balancing system is equal to the pressure of the spent renal failure therapy fluid flowing from the balancing system.

7. The renal therapy method of claim 6, which includes electronically controlling the flow of the fresh renal therapy fluid and the flow of the spent renal therapy fluid for the balancing system using fresh and spent renal therapy fluid pressure sensors.

8. The renal therapy method of claim 7, which includes electronically controlling the flow of the fresh renal therapy fluid and the flow of the spent renal therapy fluid for the balancing system by operating a plurality of valves.

9. The renal therapy method of claim 7, wherein detecting the fresh and spent renal therapy fluid pressures includes using fresh and spent pressure sensors, respectively, placed at least one of (i) upstream or (ii) downstream of the balancing system.