INFUSION FLOW INTERRUPTION METHOD AND APPARATUS

• US 20080161723A1
• Filed: 09/06/2007
• Published: 07/03/2008
• Est. Priority Date: 09/06/2006
• Status: Abandoned Application

• Current Assignee: OptiScan Biomedical Corporation
• Original Assignee: OptiScan Biomedical Corporation
• Inventors: Braig, James R., Keenan, Richard, Rule, Peter, Chiou, Jeffrey
• Application Number:
  US11/850,972
• Publication Number:
  US 20080161723A1
• Time in Patent Office: Days
• US Class Current: 600/573
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14557 specially adapted to extracorporeal circuits
• CPC Class Codes: A61B 5/15003 for venous or arterial blood
• CPC Class Codes: A61B 5/150221 Valves
• CPC Class Codes: A61B 5/150229 Pumps for assisting the blood sampling
• CPC Class Codes: A61B 5/150236 Pistons, i.e. cylindrical bodies that sit inside the syringe barrel, typically with an air tight seal, and slide in the barrel to create a vacuum or to expel blood
• CPC Class Codes: A61B 5/150244 Rods for actuating or driving the piston, i.e. the cylindrical body that sits inside the syringe barrel, typically with an air tight seal, and slides in the barrel to create a vacuum or to expel blood
• CPC Class Codes: A61B 5/150267 Modular design or construction, i.e. subunits are assembled separately before being joined together or the device comprises interchangeable or detachable modules
• CPC Class Codes: A61B 5/150305 Packages specially adapted for piercing devices or blood sampling devices kits for diabetes A61M5/003; packaging in general B65D
• CPC Class Codes: A61B 5/150755 Blood sample preparation for further analysis, e.g. by separating blood components or by mixing
• CPC Class Codes: A61B 5/150786 Optical identification systems, e.g. bar codes, colour codes
• CPC Class Codes: A61B 5/150824 by visual feedback
• CPC Class Codes: A61B 5/150854 long distance, e.g. between patient's home and doctor's office
• CPC Class Codes: A61B 5/153 Devices specially adapted for taking samples of venous or arterial blood, e.g. with syringes
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61M 1/3609 Physical characteristics of the blood, e.g. haematocrit, urea
• CPC Class Codes: A61M 1/36222 Details related to the interface between cassette and machine
• 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 1/36226 : Constructional details of cassettes, e.g. specific details on material or shape
• CPC Class Codes: A61M 1/362266 : Means for adding solutions or substances to the blood
• CPC Class Codes: A61M 2005/1404 : Keep vein-open rate [KVO], i.e. low flow rate
• CPC Class Codes: A61M 2005/1726 : the body parameters being measured at, or proximate to, the infusion site
• CPC Class Codes: A61M 2230/201 : Glucose concentration
• CPC Class Codes: A61M 5/14 : Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
• CPC Class Codes: A61M 5/1415 : Stands, brackets or the like for supporting infusion accessories

Abstract

Disclosed are systems, apparatus and methods for determining information related to analyte(s) (e.g., concentration) in a sample such as biological fluid. An analysis system for determining information relating to at least one analyte in a sample of biological fluid can be configured to: withdraw the sample of biological fluid from the source of biological fluid; interrupt the flow of infusion fluid while the sample of biological fluid is withdrawn; analyze the withdrawn biological fluid to determine information relating to at least one analyte; and resume the flow of infusion fluid after the sample of biological fluid is withdrawn. A method of interrupting flow of an infusion fluid without triggering an alarm can comprise, while the flow of the infusion fluid is interrupted, diverting the flow of the infusion fluid from a fluid passageway to an expandable volume at a rate that maintains constant flow from an infusion pump.

Claims

1. An analysis system for determining information relating to at least one analyte in a sample of biological fluid, the system comprising:

a first fluid passageway having a biological fluid input end, said first fluid passageway in fluid communication with a source of biological fluid through said biological fluid input end;

a source of infusion fluid in fluidic communication with said first fluid passageway through a second fluid passageway that is configured to maintain a flow of infusion fluid through the biological fluid input end of the first fluid passageway; and

an analyte measurement system comprising a sample cell in fluid communication with said first and second fluid passageway through a third fluid passageway, said analyte measurement system configured to measure the concentration of at least one analyte in a sample of biological fluid;

wherein the analysis system is configured to;

withdraw the sample of biological fluid from the source of biological fluid through the biological fluid input end of the first fluid passageway;

interrupt the flow of infusion fluid while the sample of biological fluid is withdrawn;

analyze the withdrawn biological fluid to determine information relating to at least one analyte; and

resume the flow of infusion fluid after the sample of biological fluid is withdrawn.

2. The system of claim 1, wherein said infusion fluid comprises saline.

3. The system of claim 1, further comprising a first pump to maintain said flow of infusion fluid.

4. The system of claim 3, wherein the first pump is bi-directional.

5. The system of claim 1, further comprising a junction to provide fluidic connection between the first passageway and the second passageway.

6. The system of claim 1, further comprising a first valve disposed along the second fluid passageway wherein the first valve is configured to interrupt the flow of the infusion fluid.

7. The system of claim 6, wherein the second fluid passageway further comprises an expandable portion located upstream from the first valve along said second fluid passageway, said expandable portion configured to store infusion fluid when the flow of infusion fluid is interrupted.

8. The system of claim 7, wherein the expandable portion comprises an expandable inner sleeve and an expandable outer sleeve that is attached to the outside of the second fluid passageway.

9. The system of claim 7, wherein the expandable portion is configured to receive infusion fluid from said second fluid passageway through one or more ports, wherein the one or more ports provide fluid communication between said expandable portion and said second fluid passageway.

10. The system of claim 8, wherein the expandable outer sleeve is configured to apply a variable pressure on the expandable inner sleeve.

11. The system of claim 10, further comprising a controller configured to control the variable pressure applied to the expandable inner sleeve and allow the infusion fluid to enter or exit the expandable portion.

12. The system of claim 10, wherein the variable pressure is controlled by an external pressure source.

13. The system of claim 7, wherein the expandable portion comprises an elastic material.

14. The system of claim 1 further comprising a fourth fluid passageway in communication with the second fluid passageway.

15. The system of claim 14, further comprising a second pump, which is in fluid communication with the fourth fluid passageway,

wherein the second pump is configured to store the flow of the infusion fluid when interrupted.

16. The system of claim 15, further comprising a pressure sensor.

17. The system of claim 7, wherein the system is configured to release the stored infusion fluid from the expandable portion into the first fluid passageway after the sample of biological fluid is withdrawn.

18. The system of claim 15, wherein the system is configured to release the stored infusion fluid from the second pump in to the first fluid passageway after the sample of biological fluid is withdrawn.

19. A method of interrupting the flow of an infusion fluid without triggering an alarm, the method comprising:

providing a flow of an infusion fluid from a source of infusion fluid through a first fluid passageway using an infusion pump;

interrupting the flow of the infusion fluid periodically;

while the flow of the infusion fluid is interrupted, diverting the flow of the infusion fluid from the first fluid passageway to an expandable volume at a rate that maintains constant flow from the infusion pump;

storing the infusion fluid in the expandable volume;

after interrupting, releasing the stored infusion fluid from the expandable volume into the first fluid passageway; and

resuming the flow of the infusion fluid from the source of infusion fluid.

20. The method of claim 19, wherein the expandable volume comprises a resilient portion disposed along the first fluid passageway.

21. The method of claim 19, wherein the expandable volume comprises a syringe pump in fluid communication with the first fluid passageway through a second fluid passageway.

22. The method of claim 19, wherein interrupting the flow of the infusion fluid comprises closing a valve to pinch off the first fluid passageway.

23. The method of claim 19, wherein diverting the flow of infusion fluid comprises maintaining at the infusion pump a flow rate that is approximately constant both during flow and during interruption of flow.

24. The method of claim 19, wherein releasing the stored infusion fluid comprises releasing the stored infusion fluid at a flow rate low enough so that fluid pressure in the first fluid passageway does not exceed an upper threshold pressure value of the alarm.

25. The method of claim 19, wherein releasing the stored infusion fluid comprises releasing the stored infusion fluid within a time duration that does not exceed a threshold time duration for triggering the alarm.