Systems and methods for monitoring introduction of a processing fluid during a fluid processing procedure

• US 6,466,879 B1
• Filed: 07/13/2000
• Issued: 10/15/2002
• Est. Priority Date: 07/13/2000
• Status: Expired due to Fees

• Current Assignee: Baxter International Inc.
• Original Assignee: Baxter International Inc.
• Inventors: Cantu, Robert J, Stinoff, Russel
• Primary Examiner(s): WACHSMAN, HAL D
• Application Number:
  US09/615,390
• Time in Patent Office: 824 Days
• Field of Search: 702/50, 702/45, 702/46, 702/19, 702/21, 702/31, 702/32, 702/55, 702/100, 702/114, 702/127, 702/129, 702/137, 702/156, 702/173, 702/174, 702/175, 702/176-178, 702/182, 702/183, 702/187, 702/188, 702/FOR.113, 702/FOR.119, 702/FOR.121, 702/FOR.127, 702/FOR.128, 702/FOR.139, 702/FOR.135, 702/FOR.149, 702/FOR-152, 702/FOR-170, 377/19-21, 604/30, 604/4.01, 604/5.01, 604/6.01, 604/6.05, 435/2, 422/67, 422/73, 436/10, 700/266, 700/281-283, 700/240, 210/645, 210/647, 210/782, 210/739, 494/37, 177/1, 177/3, 177/4, 177/25.19, 177/25-1-
• US Class Current: 702/50
• CPC Class Codes: A61M 1/3616 Batch-type treatment
• CPC Class Codes: A61M 1/3672 Means preventing coagulation
• CPC Class Codes: A61M 2205/3393 by weighing the reservoir
• CPC Class Codes: G01F 11/006 Details or accessories general details G01F15/00
• CPC Class Codes: G01F 23/20 by measurement of weight, e.g. to determine the level of stored liquefied gas
• CPC Class Codes: G01F 9/003 by measuring the weight

Abstract

Fluid processing systems and methods make use of a replenishable source containing a volume of a processing fluid that is dispensed during a processing period. A processor serves to sequentially pause and resume the processing period. The processor records weight values of the source at commencement of the processing period; upon pauses in the processing period; and upon resumptions of the processing period. At termination of the processing period, the processor generates a total volume value of processing fluid dispensed from the source during the processing period, which takes into account replenishment of the processing fluid when the processing period is paused. The systems and methods can be integrated into blood processing circuits to monitor the introduction of anticoagulant.

Claims

1. A fluid processing system comprising

a replenishable source containing a volume of a processing fluid having a known density,

a circuit to dispense the processing fluid from the source during a processing period,

a weigh sensor coupled to the source and operating to sense weight of the source that is proportional to volume of processing fluid present in the source, and

a processor coupled to the weigh sensor and operating in response to commands to sequentially pause and resume the processing period, the processor including a counting function that operates in processing steps to (i) record a current weight value of the source at commencement of the processing period;

(ii) register a first subsequent weight value (Wt1) of the source upon pause in the processing period;

(iii) register a second subsequent weight value (Wt2) of the source upon resumption of the processing period after the pause;

(iv) generate an updated current weight value upon resumption of the processing period by adding to the current weight value the difference between Wt2 and Wt1;

(v) register a final weight value of the source at termination of the processing period; and

(vi) generate a total volume value of processing fluid dispensed from the source during the processing period, which takes into account replenishment of the processing fluid when the processing period is paused, by subtracting the final weight value from the updated current weight value.

2. A system according to claim 1

wherein the processor includes a weigh function to compare a weight value of the source to a set low threshold and generate a pause command when the weight value is at or below the set low threshold.

3. A system according to claim 1

wherein the processor includes an input device to receive pause or resumption commands from an operator.

4. A system according to claim 1

wherein the processor operates to repeat processing steps (ii), (iii), and (iv) to generate an updated current weight value each time the processing period is paused and resumed.

5. A blood processing system comprising

a blood processing circuit including a device operating to separate blood into component parts,

an auxiliary line operating to convey a processing fluid into the blood processing circuit,

a replenishable source coupled to the auxiliary line, the source containing a volume of a processing fluid having a known density,

a weigh sensor coupled to the source and operating to sense weight of the source that is proportional to volume of processing fluid present in the source, and

a processor coupled to the weigh sensor and operating in response to commands to sequentially pause and resume a processing period using the blood processing circuit, the processor including a counting function that operates in processing steps to (i) record a current weight value of the source at commencement of the processing period;

(ii) register a first subsequent weight value (Wt1) of the source upon pause in the processing period;

(iii) register a second subsequent weight value (Wt2) of the source upon resumption of the processing period after the pause;

(iv) generate an updated current weight value upon resumption of the processing period by adding to the current weight value the difference between Wt2 and Wt1;

(v) register a final weight value of the source at termination of the processing period; and

(vi) generate a total volume value of processing fluid dispensed from the source during the processing period, which takes into account replenishment of the processing fluid when the processing period is paused, by subtracting the final weight value from the updated current weight value.

6. A system according to claim 5

wherein the processing fluid comprises an anticoagulant solution.

7. A system according to claim 5

wherein the processor includes a weigh function to compare a weight value of the source to a set low threshold and generate a pause command when the weight value is at or below the set low threshold.

8. A system according to claim 5

wherein the processor includes an input device to receive pause or resumption commands from an operator.

9. A system according to claim 5

wherein the processor operates to repeat processing steps (ii), (iii), and (iv) to generate an updated current weight value each time the processing period is paused and resumed.

10. A method for monitoring volume of processing fluid introduced into a fluid processing system comprising the steps of

establishing a replenishable source containing a volume of a processing fluid having a known density,

dispensing the processing fluid from the source during a processing period,

sensing weight of the source that is proportional to volume of processing fluid present in the source,

recording a current weight value of the source at commencement of the processing period,

registering a first subsequent weight value (Wt1) of the source upon a pause in the processing period,

registering a second subsequent weight value (Wt2) of the source upon a resumption of the processing period after the pause,

generating an updated current weight value upon resumption of the processing period by adding to the current weight value the difference between Wt2 and Wt1,

registering a final weight value of the source at termination of the processing period, and

generating a total volume value of processing fluid dispensed from the source during the processing period, which takes into account replenishment of the processing fluid when the processing period is paused, by subtracting the final weight value from the updated current weight value.

11. A method according to claim 10

further including the step of comparing a weight value of the source to a set low threshold and generate a command to pause the processing period when the weight value is at or below the set low threshold to prompt an operator to replenish the processing fluid.

12. A method according to claim 10 further including receiving pause or resumption commands from an operator.

13. A method according to claim 10 including the step of generating an updated current weight value each time the processing period is paused and resumed.

14. A blood processing method comprising the steps of

establishing a blood processing circuit,

establishing a replenishable source containing a volume of a processing fluid having a known density,

dispensing the processing fluid from the source into the blood processing circuit during a processing period,

sensing weight of the source that is proportional to volume of processing fluid present in the source,

recording a current weight value of the source at commencement of the processing period,

registering a first subsequent weight value (Wt1) of the source upon a pause in the processing period,

registering a second subsequent weight value (Wt2) of the source upon a resumption of the processing period after the pause,

generating an updated current weight value upon resumption of the processing period by adding to the current weight value the difference between Wt2 and Wt1,

registering a final weight value of the source at termination of the processing period, and

generating a total volume value of processing fluid dispensed from the source during the processing period, which takes into account replenishment of the processing fluid when the processing period is paused, by subtracting the final weight value from the updated current weight value.

15. A method according to claim 14

wherein the blood processing circuit circulates blood from a donor through a blood separation device.

16. A method according to claim 15

wherein the processing fluid comprises an anticoagulant solution that is added to the blood.

17. A method according to claim 14

further including the step of comparing a weight value of the source to a set low threshold and generate a command to pause the processing period when the weight value is at or below the set low threshold to prompt an operator to replenish the processing fluid.

18. A method according to claim 14

further including receiving pause or resumption commands from an operator.

19. A method according to claim 14

including the step of generating an updated current weight value each time the processing period is paused and resumed.