Extracorporeal blood processing system

• US 6,764,460 B2
• Filed: 07/24/2001
• Issued: 07/20/2004
• Est. Priority Date: 09/12/1997
• Status: Expired due to Term

• Current Assignee: Terumo BCT, Inc. (Terumo Corporation)
• Original Assignee: Gambro, Inc. (DaVita Incorporated)
• Inventors: Kappus, John J., Brierton, Mark Joseph, Dolecek, Victor D.
• Primary Examiner(s): Bianco, Patricia
• Application Number:
  US09/911,955
• Publication Number:
  US 20020028155A1
• Time in Patent Office: 1,092 Days
• Field of Search: 604/4.01, 604/5.01, 604/6-1-, 604/6.1, 604/6.11, 604/6.16, 604/19, 604/27-31, 604/34, 604/65-67, 604/153, 422/44, 210/787-89, 210/645, 210/739, 210/741, 210/767, 210/781, 210/722, 210/85, 210/87, 210/90, 210/252, 210/258-60, 210/257--25, 210/321.6, 210/321.72, 210/359, 210/360.1, 128/DIG.3, 128/905, 128/920, 128/923, 494/1, 494/10, 494/37, 494/60, 494/61, 73/10.1, 73/15.7, 73/15.9, 73/18.7, 73/37, 738/61, 731/95, 731/98--99, 738/614--86, 738/616.9, 732/32, 732/62--71
• US Class Current: 604/6.01
• CPC Class Codes: A61M 1/36222 Details related to the interface between cassette and machine
• CPC Class Codes: A61M 1/36223 the cassette being adapted for heating or cooling the blood
• 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 1/3624 Level detectors; Level control
• CPC Class Codes: A61M 1/3639 Blood pressure control, pressure transducers specially adapted therefor
• CPC Class Codes: A61M 1/3641 Pressure isolators
• CPC Class Codes: A61M 1/3652 using gas, e.g. air
• CPC Class Codes: A61M 1/3693 using separation based on different densities of components, e.g. centrifuging
• 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 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2205/123 with incorporated reservoirs
• CPC Class Codes: A61M 2205/125 with incorporated filters
• CPC Class Codes: A61M 2205/128 with incorporated valves
• CPC Class Codes: A61M 2205/14 Detection of the presence or absence of a tube, a connector or a container in an apparatus
• CPC Class Codes: A61M 2205/3382 Upper level detectors
• CPC Class Codes: A61M 2205/3386 Low level detectors
• CPC Class Codes: A61M 2205/505 Touch-screens; Virtual keyboard or keypads; Virtual buttons; Soft keys; Mouse touches
• CPC Class Codes: B04B 2005/045 having annular separation channels
• CPC Class Codes: B04B 5/0442 with means for adding or withdrawing liquid substances during the centrifugation, e.g. continuous centrifugation
• CPC Class Codes: B04B 9/08 : Arrangement or disposition of transmission gearing for solid bowl screw centrifuges B04B1/2016; Couplings; Brakes

Abstract

An extracorporeal blood processing system including a disposable assembly that has integral fluid passageways. A blood removal conduit and a blood return conduit are interconnected with the integral fluid passageways. A diaphragm is mounted in the disposable assembly and is removably attachable to a sensor via a number of connection devices. In one embodiment, the sensor may include a transducer that is capable of measuring the force exerted on the diaphragm. The corresponding force may be correlated to a pressure of fluid in either the blood removal conduit and/or the blood return conduit.

Claims

1. An extracorporeal blood processing system in which blood is removed from an individual for processing and returned to the individual, said system comprising:

a blood removal conduit for transferring blood from a donor/patient;

a blood return conduit for transferring blood to a donor/patient;

said blood removal conduit and said blood return conduit being in fluid communication; and

a disposable assembly including a pressure sensing station and a plurality of integral passageways for transporting blood, each of said plurality of integral passageways being partially defined by at least one of said blood removal conduit and said blood return conduit;

said pressure sensing station including a diaphragm member mounted to said disposable assembly, said diaphragm member having a first surface being in direct fluid communication with one of at least said blood removal conduit and said blood return conduit, said diaphragm member being movably responsive in relation to the fluid pressure commonly occurring within each of such blood removal and blood return conduits;

a sensor for determining a pressure in one of at least said blood removal conduit and said blood return conduit; and

means for removably attaching a second surface of said diaphragm to said sensor wherein said pressure sensing station co-acts with said sensor to measure the fluid pressure commonly occurring within each of said blood removal and blood return conduits.

2. An extracorporeal system, as claimed in claim 1, wherein said sensor includes a force sensor for measuring a force exerted by fluid on said first surface of said diaphragm member, said force corresponding to a pressure of fluid in at least one of said blood removal conduit and said blood return conduit.

3. An extracorporeal system, as claimed in claim 1, wherein said disposable assembly comprises a molded cassette member.

4. An extracorporeal system, as claimed in claim 1, wherein said diaphragm member comprises a flexible elastomeric material.

5. An extracorporeal system, as claimed in claim 1, wherein said means for removably attaching further comprises:

a ferromagnetic material attached to said second surface of said diaphragm member; and

a magnet attached to said sensor for coupling to said ferromagnetic material.

6. An extracorporeal system, as claimed in claim 1, wherein said means for removably attaching further comprises:

a magnet attached to said second surface of said diaphragm member; and

a ferromagnetic material attached to said sensor for coupling to said magnet.

7. An extracorporeal system, as claimed in claim 1, wherein said sensor includes a strain gauge.

8. An extracorporeal system, as claimed in claim 1, wherein said sensor measures positive and negative pressures in said at least one of said blood removal conduit and said blood return conduit.

9. An extracorporeal system, as claimed in claim 1, wherein said sensor measures a pressure of blood being removed from said donor/patient and a pressure of blood being returned to said donor/patient.

10. An extracorporeal system, as claimed in claim 1, wherein said extracorporeal blood processing system is an apheresis system.

11. An extracorporeal blood processing system, as claimed in claim 1, wherein said means for removably attaching further comprises:

a probe having a vacuum chamber for interfacing with said second surface of said diaphragm member, said probe being interconnected to said sensor,

wherein a vacuum created in said vacuum chamber couples said probe to said second surface of said diaphragm member.

12. A disposable assembly, as claimed in claim 1, further comprising means for detecting a state of coupling between said vacuum chamber and said second surface of said diaphragm member.

13. An extracorporeal blood processing system, as claimed in claim 1, wherein:

said diaphragm member further comprising;

an elongated member attached to and extending from said second surface of said diaphragm member; and

said means for attaching further comprising;

means for capturing connected to said sensor, said means for capturing engaging said elongated member.

14. An extracorporeal blood processing system, as claimed in claim 1, wherein

said diaphragm member further comprises:

an elongated member attached to and extending from said second surface of said diaphragm member, said elongated member having a shaped end; and

said means for attaching further comprising;

a receiving element having a first opening, said first opening having a first size for inserting said shaped end into said receiving element and said opening having a second size for capturing said shaped end in said receiving element, said first size being larger than said second size.

15. An extracorporeal blood processing system, as claimed in claim 14, wherein said means for attaching further comprises:

said receiving element having surfaces defining a second opening;

a cam positioned within said second opening; and

a solenoid attachable to said cam, wherein said solenoid moves said cam against said surfaces defining a second opening to cause said first opening to expand and contract from said first size to said second size.

16. An extracorporeal blood processing system as claimed in claim 14, wherein said receiving element further comprises:

a first body piece;

a second body piece, said first and second body pieces defining said opening; and

a hinge element connecting said first and second body pieces, wherein said hinge element causes said first opening to expand and contract from said first size to said second size.

17. An extracorporeal blood processing system as claimed in claim 14, wherein said receiving element further comprises:

a single section being closed at a first end and having a gap at a second end, said gap further defining said first opening;

said gap being expanded and contracted within the elastic range of said single section causing said first opening to expand and contract from said first size to said second size.

18. An extracorporeal blood processing system, as claimed in claim 1, wherein:

said diaphragm member further comprises;

an elongated member attached to said second surface of said diaphragm member, said elongated member includes a shaped end; and

said means for attaching further comprising;

a receiving structure having a opening, said opening having a complementary shape corresponding with said shaped end, wherein said opening captures said shaped end.

19. A disposable assembly, as claimed in claim 1, further comprising:

a single needle, in direct fluid communication with said blood removal conduit and blood return conduit, for removal of blood from and return of blood to said donor/patient.

20. A method for measuring pressure in an extracorporeal blood processing system, comprising the steps of:

introducing blood from a donor/patient into a disposable assembly having at least one blood conduit, said at least one blood conduit having a diaphragm member disposed within a wall of said at least one blood conduit; and

determining a pressure in said at least one blood conduit comprising

measuring a force of said blood on said diaphragm using a sensor comprising

measuring strain exerted on said diaphragm by said blood by using a strain gauge; and

measuring stress exerted on said diaphragm by said blood by using a strain gauge; and

calculating a pressure of said blood in said at least one blood conduit using the force exerted on said diaphragm member obtained from said measuring step.

21. The method, as claimed in claim 20, wherein said sensor is removably coupled to said diaphragm member.