Method and device for regulating fluid pump pressures

• US 7,421,316 B2
• Filed: 10/25/2004
• Issued: 09/02/2008
• Est. Priority Date: 07/10/2000
• Status: Expired due to Term

• Current Assignee: Deka Products Limited Partnership
• Original Assignee: Deka Products Limited Partnership
• Inventors: Gray, Larry, Bryant, Robert
• Primary Examiner(s): DeCady; Albert
• Assistant Examiner(s): Stevens; Thomas H
• Application Number:
  US10/972,982
• Publication Number:
  US 20050118038A1
• Time in Patent Office: 1,408 Days
• Field of Search: 700/282, 417/38, 417/53, 417/313, 417/32, 417/20, 137/1, 210/767, 604/141
• US Class Current: 700/282
• CPC Class Codes: A61M 1/152 Details related to the interface between cassette and machine
• CPC Class Codes: A61M 1/155 with treatment-fluid pumping means or components thereof
• CPC Class Codes: A61M 1/1565 Details of valves
• CPC Class Codes: A61M 1/159 specially adapted for peritoneal dialysis
• CPC Class Codes: A61M 1/282 Operational modes
• CPC Class Codes: A61M 2205/3331 Pressure; Flow
• CPC Class Codes: A61M 5/16809 by repeated filling and emptying of an intermediate volume pressure infusion using positive displacement pumps A61M5/142
• CPC Class Codes: F04B 43/06 Pumps having fluid drive
• CPC Class Codes: G05D 16/2073 with a plurality of pressure sources
• CPC Class Codes: G05D 7/0635 by action on throttling means G05D7/0688, G05D7/0694 take precedence
• CPC Class Codes: Y10T 137/0318 Processes

Abstract

A method is provided for regulating fluid pump pressures by detecting an elevation differential between a fluid flow control device and the distal end of a fluid line in communication with the fluid flow control device. A fluid flow control device, for instance a peritoneal dialysis device, is at a first height, a distal end of a fluid line is at a second height, and a valved outlet, when open, affords communication between the fluid flow control device and the distal end of the fluid line. The elevation differential is correlatable with a pressure measurable during a calibration procedure provided as a part of the methodology.

Claims

1. A computer program product residing on a computer readable medium for use on a processor for determining an elevation differential between a first location and a second location, wherein a fluid flow control device is located at the first location, the fluid flow control device including at least one liquid volume in valved communication with the second location, the second location in fluid communication with a distal end of a fluid line, the computer program product comprising a computer usable medium having computer readable program code thereon, the computer readable program code including:

program code for reading and storing pressure values within pumps;

program code for computing and identifying correlations between stored pressure values;

program code for calculating pressure values based on the identified correlations; and

program code for estimating the elevation differential based upon calculated pressures.

2. The computer program product according to claim 1, further comprising:

program code for calculating a desired pumping pressure based upon the elevation differential; and

program code for adjusting the pumping pressured within the fluid flow control device in accordance with the desired pumping pressure.

3. A computer program product for use on a processor for regulating fluid pump pressures, wherein a fluid flow control device is located at a first location, the fluid flow control device including at least one liquid volume in valved communication with a second location, the second location in fluid communication with a distal end of a fluid line;

the computer program product comprising a computer usable medium having computer readable program code thereon, the computer readable program code including;

program code for reading and storing pressure values within the pumps;

program code for computing and identifying correlations between stored pressure values;

program code for calculating pressure values based on the identified correlations; and

program code for calculating a desired pumping pressure based on the identified correlations.

4. A computer program product residing on a computer readable medium having a plurality of instructions stored thereon for determining an elevation differential between a first location and a second location, wherein a fluid flow control device is located at the first location, the fluid flow control device including at least one liquid volume in valved communication with the second location, the second location in fluid communication with a distal end of a fluid line, which, when executed by a processor, cause the processor to perform operations comprising:

calibrating a pressure in the liquid volume;

establishing communication between the liquid volume and the distal end;

measuring a pressure associated with the liquid volume; and

adjusting a fluid pump pressure in accordance with the measured pressure.

5. The computer program product of claim 4 wherein calibrating the liquid volume comprising:

isolating the liquid volume from the distal end;

measuring a first calibration pressure of a control volume in pressure communication with the liquid volume;

pressurizing the liquid volume; and

measuring a second calibration pressure of the control volume.

6. A computer program product residing on a computer readable medium having a plurality of instructions stored thereon which, when executed by a processor, cause the processor to perform operations comprising:

reading and storing pressure values;

computing and identifying a correlation between the pressure values;

calculating pressure values based on the identified correlations; and

estimating an elevation differential based upon the calculated pressures.

7. A computer program product residing on a computer readable medium having a plurality of instructions stored thereon which, when executed by a processor, cause the processor to perform operations comprising:

reading and storing fluid pressure values from at least one membrane pump and a distal end of a fluid line;

computing and identifying a difference between the pressure values; and

estimating an elevation differential between the at least one membrane pump and the distal end of the fluid line based upon the calculated pressures.

8. The computer program product as claimed in claim 7 further comprising adjusting the pressure of the membrane pump.

9. The computer program product as claimed in claim 8 wherein the at least one membrane pump is a pneumatically actuated membrane pump.

10. The computer program product as claimed in claim 9 wherein the membrane of the membrane pump is a flexible membrane.

11. The computer program product as claimed in claim 10 wherein the membrane pump is formed in a cassette.

12. The computer program product as claimed in claim 11 wherein the pneumatic actuation causes the membrane to press against the cassette.

13. A computer program product residing on a computer readable medium having a plurality of instructions stored thereon which, when executed by a processor that controls a peritoneal dialysis machine, causes the peritoneal dialysis machine to perform operations comprising:

determining pressure in at least one membrane pump for pumping dialysate, the membrane pump being in fluid communication with at least one valve for controlling flow of dialysate pumped by the membrane pump;

determining the pressure at a distal end of a fluid line in fluid communication with the membrane pump;

calculating a pressure differential between the pressure in the at least one membrane pump and the pressure at the distal end of a fluid line; and

correlating the pressure differential to determine the location of the distal end relative to the pump.

14. The computer program product as claimed in claim 13 further comprising adjusting the pressure of the membrane pump.

15. The computer program product as claimed in claim 14 wherein the at least one membrane pump is a pneumatically actuated membrane pump.

16. The computer program product as claimed in claim 15 wherein the membrane of the membrane pump is a flexible membrane.

17. The computer program product as claimed in claim 16 wherein the membrane pump is formed in a cassette.

18. The computer program product as claimed in claim 17 wherein the pneumatic actuation causes the membrane to press against the cassette.