Blood processing systems with fluid flow cassette with a pressure actuated pump chamber and in-line air trap

• US 6,716,004 B2
• Filed: 11/04/2002
• Issued: 04/06/2004
• Est. Priority Date: 09/03/1999
• Status: Expired due to Term

• Current Assignee: Fenwal Incorporated (Fresenius SE & Co. KGaA)
• Original Assignee: Baxter International Inc.
• Inventors: Vandlik, Mark R, Westberg, Tom
• Primary Examiner(s): Yu, Justine R.
• Assistant Examiner(s): Rodriguez, William H.
• Application Number:
  US10/287,560
• Publication Number:
  US 20030138334A1
• Time in Patent Office: 519 Days
• Field of Search: 417/313, 417/477, 417/63, 210/745, 422/44, 137/881, 494/37, 384/138, 554/82, 555/03
• US Class Current: 417/477.2
• 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• CPC Class Codes: A61M 1/302 having a reservoir for withdrawn untreated blood
• CPC Class Codes: A61M 1/303 having a reservoir for treated blood to be returned
• 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 1/362227 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/36225 with blood pumping 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 1/362266 Means for adding solutions or substances to the blood
• CPC Class Codes: A61M 1/3696 with means for adding or withdrawing liquid substances during the centrifugation, e.g. continuous centrifugation
• CPC Class Codes: A61M 2205/128 with incorporated valves
• CPC Class Codes: A61M 2205/331 used as turbidity change detectors, e.g. for priming-blood or plasma-hemoglubine-interface detection
• CPC Class Codes: A61M 2205/3393 by weighing the reservoir
• CPC Class Codes: A61M 60/109 incorporated within extracorporeal blood circuits or systems
• CPC Class Codes: A61M 60/113 in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/36 for specific blood treatment; for specific therapy
• CPC Class Codes: A61M 60/43 using vacuum at the blood pump, e.g. to accelerate filling
• CPC Class Codes: A61M 60/847 arranged in a cassette
• CPC Class Codes: A61M 60/851 : Valves
• CPC Class Codes: A61M 60/892 : Active valves, i.e. actuated by an external force
• CPC Class Codes: A61M 60/894 : Passive valves, i.e. valves actuated by the blood
• CPC Class Codes: F04B 13/02 : of two or more fluids at the same time
• CPC Class Codes: F04B 2205/09 : Flow through the pump
• CPC Class Codes: F04B 43/026 : each plate-like pumping flexible member working in its own pumping chamber
• CPC Class Codes: F04B 49/065 : and making use of computers
• CPC Class Codes: Y10T 137/87861 : Spring coaxial with valve

Abstract

A blood processing system comprises a processing chamber to process blood and a fluid flow cassette that communicates with the processing chamber. The cassette comprises a body, a pump chamber formed in the body, and a flexible diaphragm on the pump chamber responsive to an applied fluid pressures for flexure toward and away from the pump chamber to pump fluid through the pump chamber. The cassette also includes a flow path formed, at least in part, in the body to couple the pump chamber in fluid flow communication with the processing chamber, to convey fluid pumped by the pump chamber into the processing chamber. The cassette also includes an in line cavity formed in the body and located in the flow path to trap air to prevent entry of air into the processing chamber.

Claims

1. A blood processing system comprising

a processing chamber to process blood, and

a fluid flow cassette communicating with the processing chamber comprising

a body,

a pump chamber formed in the body,

a flexible diaphragm on the pump chamber responsive to an applied fluid pressures for flexure toward and away from the pump chamber to pump fluid through the pump chamber,

a flow path formed, at least in part, in the body, to couple the pump chamber in fluid flow communication with the processing chamber, to convey fluid pumped by the pump chamber into the processing chamber, and

an in line cavity formed in the body and located in the flow path to trap air to prevent entry of air into the processing chamber.

2. A system according to claim 1

wherein the processing chamber separates blood into components.

3. A system according to claim 1

wherein the fluid flow cassette includes a valve in the body communicating with the pump chamber, and a flexible diaphragm on the valve responsive to fluid pressures for flexure to open and close the valve in concert with operation of the pump chamber.

4. A system according to claim 1

wherein the fluid flow cassette includes a second cavity in the body communicating with the pump chamber, the second cavity including a blood filtration media.

5. A blood processing system comprising

a processing chamber to process blood, and

a fluid flow cassette communicating with the processing chamber comprising

a body,

a pump chamber formed in the body,

a flexible diaphragm on the pump chamber responsive to fluid pressures applied in pulsatile pump strokes for flexure toward and away from the pump chamber to pump fluid through the pump chamber,

a flow path formed, at least in part, in the body to couple the pump chamber in fluid flow communication with the processing chamber, to convey fluid pumped by the pump chamber into the processing chamber, and

an in line cavity formed in the body and located in the flow path to trap air and serve as a capacitor to dampen the pulsatile pump strokes.

6. A system according to claim 5

wherein the processing chamber separates blood into components.

7. A system according to claim 5

wherein the fluid flow cassette includes a valve in the body communicating with the pump chamber, and a flexible diaphragm on the valve responsive to fluid pressures for flexure to open and close the valve in concert with operation of the pump chamber.

8. A system according to claim 5

wherein the fluid flow cassette includes a second cavity communicating with the pump chamber, the second cavity including a blood filtration media.