Method and apparatus for testing blood glucose in a reversible infusion line

• US 20070179437A1
• Filed: 04/19/2006
• Published: 08/02/2007
• Est. Priority Date: 02/02/2006
• Status: Active Grant

• Current Assignee: Palco Laboratories
• Original Assignee: Henry Grage, Paul Levin
• Inventors: Levin, Paul, Grage, Henry
• Granted Patent: US 7,367,942 B2
• Time in Patent Office: Days
• US Class Current: 604/66
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61M 5/14228 with linear peristaltic action, i.e. comprising at least three pressurising members or a helical member

Abstract

An apparatus for automatically and periodically measuring a patient'"'"'s blood glucose level wherein the patient has a catheter in a blood vessel and is receiving infusion fluid through the catheter. A testing unit is provided which has a main infusion channel and, in a preferred embodiment, the testing unit includes a side channel. The side channel has a restrictive cross-sectional area compared with the main infusion channel. A glucose test chamber is formed in the side channel. First and second valves are placed adjacent the test chamber in the side channel to isolate a blood sample for testing. The isolation of the sample provides more accurate blood glucose measurements than those provided by systems of the prior art. A second embodiment of the invention has an isolatable test chamber placed in the main infusion line and no side channel is utilized.

Claims

1. An apparatus for automatically and periodically measuring a patient'"'"'s blood glucose level comprising:

a testing unit,

infusion lines to connect said testing unit to a source of infusion fluid and to a catheter placed in a patient'"'"'s blood vessel,

reversible peristaltic pump means to move infusion fluid or blood either forwardly through said testing unit into said blood vessel catheter or backwardly into said testing unit and said infusion line,

a main channel for blood or infusion fluid within said testing unit,

a side channel in the testing unit connected to said main channel,

a test chamber within said side channel for glucose testing, and

valve means for controlling fluid flow through said main channel and isolating said test chamber in said side channel.

2. The apparatus of claim 1 wherein said valve means includes first and second valves in said side channel for isolating a blood sample in said test chamber, said first and second valves being adjacent to and on opposite sides of said test chamber.

3. The apparatus of claim 2 wherein each of said valve means is a balloon valve.

4. The apparatus of claim 2 further comprising third valve means in said main channel for diverting fluid flow into said side channel.

5. The apparatus of claim 3 wherein said third valve means is a balloon valve.

6. The apparatus of claim 5 wherein said test chamber has a volume between 8 μ

L and 12 μ

L.

7. The apparatus of claim 6 wherein said test chamber has a cross-sectional height greater than 300 microns.

8. The apparatus of claim 4 further comprising a calibration fluid channel in fluid communication with said side channel and fourth valve means in said calibration fluid channel to allow calibration fluid to flow through said side channel and said test chamber.

9. The apparatus of claim 1 wherein said testing unit is disposable.

10. A method of automatically and periodically measuring the blood glucose level of a patient wherein a patient is continuously receiving intravenous fluids through an infusion line and through a catheter inserted into a blood vessel in said patient'"'"'s body, wherein a reversible peristaltic pump operates either forwardly to pump fluid into the patient'"'"'s body or backwardly to draw blood from said patient'"'"'s blood vessel catheter, and wherein said infusion line runs through a testing unit attached to said patient'"'"'s body, comprising the steps:

reversing said peristaltic pump periodically to pump a blood sample from said patient'"'"'s blood vessel catheter into said testing unit,

directing said blood sample into a side channel of said testing unit which houses a blood glucose test chamber,

temporarily blocking the fluid communication between said test chamber and other fluid channels of said testing unit to isolate said blood sample in said test chamber, and

measuring the blood glucose level of said patient'"'"'s blood in said test chamber with an enzyme based glucose electrode.

11. An apparatus for automatically and periodically measuring a patient'"'"'s blood glucose level comprising:

a testing unit,

infusion lines to connect said testing unit to a source of infusion fluid and to a catheter placed in a patient'"'"'s blood vessel,

reversible peristaltic pump means to move infusion fluid or blood either forwardly through said testing unit into said blood vessel catheter or backwardly into said testing unit and said infusion line,

a main channel for blood or infusion fluid within said testing unit,

a test chamber within said main channel for glucose testing, and

valve means for controlling fluid flow through said main channel and isolating said test chamber.

12. The apparatus of claim 11 wherein said valve means includes first and second valves in said main channel.