Biological/pharmaceutical method and apparatus for collecting and mixing fluids

• US 5,378,227 A
• Filed: 08/11/1992
• Issued: 01/03/1995
• Est. Priority Date: 08/11/1992
• Status: Expired due to Term

• Current Assignee: Cobe Cardiovascular Incorporated (LivaNova Plc)
• Original Assignee: Cobe Cardiovascular Incorporated (LivaNova Plc)
• Inventors: O'Riordan, John F., Antwiler, Glen D.
• Primary Examiner(s): Rimell, Sam
• Application Number:
  US07/928,040
• Time in Patent Office: 875 Days
• Field of Search: 604/4, 604/19, 604/28, 604/30, 604/35, 604/65, 604/67, 604/118, 604/902
• US Class Current: 604/6.07
• CPC Class Codes: A61M 1/3624 Level detectors; Level control
• CPC Class Codes: A61M 1/3627 Degassing devices; Buffer reservoirs; Drip chambers; Blood filters
• CPC Class Codes: A61M 1/3672 Means preventing coagulation
• CPC Class Codes: A61M 1/631 Emptying the suction container without interrupting suction
• CPC Class Codes: A61M 1/68 Containers incorporating a flexible member creating suction
• CPC Class Codes: A61M 2205/3389 Continuous level detection A61M2205/3393 takes precedence
• CPC Class Codes: A61M 2205/3393 by weighing the reservoir
• CPC Class Codes: A61M 2205/7545 for solid matter, e.g. microaggregates

Abstract

A blood circulation apparatus includes a suction wand for receiving blood from a patient, a reservoir for collecting received blood, a conduit connecting the suction wand and the reservoir, an anticoagulant pump and line for introducing anticoagulant into the blood upstream of the reservoir, sensors for detecting liquid volume in the reservoir and for transmitting a corresponding volume signal, and a controller for regulating anticoagulant introduction in accordance with a predetermined program and as a function of the volume signal.

Claims

1. A blood collection apparatus, comprising:

means for receiving blood from a patient;

a reservoir for collecting received blood;

means for transporting received blood from the receiving means to the reservoir;

and means for preventing blood coagulation in reservoir, the preventing means including;

means for introducing anticoagulant into the received blood at a predetermined infusion rate before the blood leaves the reservoir;

means for sensing liquid volume in the reservoir and for transmitting a volume signal corresponding thereto; and

control means for varying the predetermined infusion rate of the anticoagulant introducing means in accordance with a predetermined program and as a function of the volume signal.

2. An apparatus according to claim 1 wherein the receiving means includes a suction wand, and the transporting means includes pump means for drawing blood through the suction wand and a conduit flow connecting the suction wand and the reservoir.

3. An apparatus according to claim 2 wherein the pump means is a vacuum pump for establishing a negative pressure within the reservoir to induce flow into the reservoir.

4. An apparatus according to claim 2 wherein the pump means includes a peristaltic pump located between the receiving means and the reservoir.

5. An apparatus according to claim 1 wherein the reservoir is a hard shell container, and the sensing means includes a plurality of optical detectors arranged on the container.

6. An apparatus according to claim 1 wherein the anticoagulant introducing means includes an anticoagulant reservoir in fluid communication with the blood collecting reservoir.

7. An apparatus according to claim 6 wherein the anticoagulant introducing means further includes a variable speed pump, and wherein the control means regulates the speed of the pump as a function of the volume signal.

8. An apparatus according to claim 1 wherein the sensing means includes a scale for weighing the blood collecting reservoir.

9. An apparatus according to claim 1 further including input means for permitting a user to vary the predetermined program.

10. An apparatus according to claim 1 wherein the control means includes means for calculating a rate of volume change of fluid in the reservoir and means for regulating the flow of anticoagulant as a function of the calculated rate of volume change.

11. An apparatus according to claim 1 further including means for emptying the blood collecting reservoir, the predetermined infusion rate of the anticoagulant being further varied in accordance with the flow rate of the emptying of the blood collecting reservoir.

12. An apparatus according to claim 11 wherein the emptying means includes a pump.

13. An apparatus according to claim 1 wherein the control means regulates the anticoagulant infusion rate as a function of the average salvage rate Qb, defined by the formula Qb=(Vinc+Vpump-Vac)/time, wherein Vinc represents a change in reservoir volume, Vpump represents a fluid volume removed from the reservoir, and Vac represents a volume of anticoagulant added to the received blood.

14. An apparatus according to claim 13 wherein the control means maintains the infusion rate of the anticoagulant in proportion to the average salvage rate Qb.

15. An apparatus according to claim 13 wherein the control means maintains the infusion rate of anticoagulant above a predetermined minimum value regardless of the value of Qb.

16. A method for collecting blood from a patient, the method comprising the steps of:

receiving blood from a patient;

transporting the received blood to a reservoir;

and regulating a mixture ratio of anticoagulant and blood in the reservoir, the step of regulating including the substeps of;

monitoring a fluid volume within the reservoir using a sensor;

outputting a volume signal corresponding to the fluid volume in the reservoir as sensed by the sensor;

introducing anticoagulant into the received blood; and

controlling the introduction of anticoagulant in accordance with a predetermined program and as a function of the volume signal.

17. A method according to claim 16 wherein the step of receiving includes the substep of suctioning blood through a suction wand.

18. A method according to claim 16 wherein the step of transporting includes the substep of conveying blood from the receiving means to the reservoir using a pump.

19. A method according to claim 16 wherein the reservoir includes a series of optical detectors selectively positioned along the height of the reservoir, and the step of monitoring includes the substep of detecting, with the optical detectors, the volume of fluid in the reservoir.

20. A method according to claim 16 wherein the step of monitoring includes the substep of weighing the reservoir.

21. A method according to claim 16 wherein the step of introducing anticoagulant includes the substep of conveying anticoagulant into the received blood using a pump.

22. A method according to claim 16 wherein the step of controlling includes the substep of regulating a speed of the pump.

23. A method according to claim 16 where the predetermined program is variable in response to data supplied by a user.

24. A method according to claim 16 wherein the step of controlling includes the substep of calculating a rate of volume change of fluid in the reservoir and regulating anticoagulant flow as a function of the calculated rate change.

25. A method according to claim 16 wherein the infusion rate of the anticoagulant is varied as a function of the average salvage rate Qb, defined by the formula Qb=(Vinc+Vpump-Vac)/time, wherein Vinc represents a change in reservoir volume, Vpump represents a fluid volume removed from the reservoir, and Vac represents a volume of anticoagulant added to the received blood.

26. A method according to claim 25 wherein the infusion rate of the anticoagulant is proportional to the average salvage rate Qb.

27. A method according to claim 25 wherein the infusion rate of anticoagulant is maintained above a predetermined minimum value regardless of the value of Qb.

28. An apparatus for controlling flow of a medical fluid into flow of a biological fluid, the apparatus comprising:

a fluid reservoir;

transporting means for conveying the biological fluid into the fluid reservoir;

conduit means flow connected to the transporting means, for conveying the medical fluid into the transported biological fluid;

and means for regulating a mixture ratio of the medical fluid to the biological fluid in the reservoir, the regulating means including;

means for detecting volume in the fluid reservoir and for transmitting a corresponding volume signal; and

control means for varying said medical fluid flow as a function of said volume signal.

29. An apparatus according to claim 28, wherein the control means includes means for calculating a rate of volume change in the reservoir and regulating the medical fluid flow as a function of the calculated rate change.

30. A method for controlling flow of a medical fluid into flow of a biological fluid, the method comprising the steps of:

transporting the biological fluid to a reservoir;

monitoring a fluid volume within the reservoir using a sensor;

and regulating a mixture ratio of the medical fluid to the biological fluid in the reservoir, the step of regulating including the substeps of;

outputting a volume signal corresponding to a fluid volume sensed by the sensor;

introducing the medical fluid into the transported biological fluid; and

controlling the introduction of the medical fluid into the biological fluid as a function of the volume signal.