Continuous glucose monitoring and a system utilized therefor

• US 4,890,621 A
• Filed: 01/19/1988
• Issued: 01/02/1990
• Est. Priority Date: 01/19/1988
• Status: Expired due to Fees

• Current Assignee: North Star Research Institute
• Original Assignee: Northstar Research Institute, Ltd.
• Inventors: Hakky, Said I.
• Primary Examiner(s): Sykes, Angela D.
• Application Number:
  US07/145,066
• Time in Patent Office: 714 Days
• Field of Search: 128/632-634, 128/637, 128/664-667, 128/719, 128/721, 128/903, 128/635, 604/65-67, 604/49-53, 356/39-41
• US Class Current: 600/316
• CPC Class Codes: A61B 5/14528 invasively
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence

Abstract

A continuous process for monitoring blood glucose level includes the steps of segregating a clear liquid component of blood from the protein and cells of the blood, wherein the clear liquid component includes the glucose to be monitored; continuously passing the clear liquid in a predetermined path between a light-emitting and a light-detecting device; detecting an optical property of the clear liquid component of the blood and employing the optical property to determine the glucose level in the blood. The invention also relates to the system for carrying out the continuous glucose monitoring process, and to a device for automatically controlling the pressure level in the system as a function of the breathing pattern of a patient in which the system is implanted.

Claims

1. A method of continuously monitoring the glucose level in a patient including the steps of:

establishing a negative pressure for aiding in separating a clear liquid component of the patient'"'"'s blood from the blood cells and proteins thereof and for continuously passing the clear liquid component in a predetermined path by connecting a pressure regulating device to spaced-apart ribs of the patient, whereby the breathing activity of the patient is employed to establish the negative pressure;

detecting an optical property of the clear component as it moves along said predetermined path; and

employing information obtained regarding the detected optical property to determine the glucose level in the blood.

2. A continuous glucose monitoring system to be employed by a patient while the patient is mobile, said system including:

microporous filter means insertable into a blood vessel of a patient for permitting a clear liquid component of the blood to filter through said filter means, said clear liquid component being separated from the blood cells and proteins of said blood and including the glucose to be monitored;

conduit means having a passage for receiving a flow of the clear liquid component from the filter means;

optical detecting means for detecting an optical property of the clear liquid component of the blood, said optical detecting means being adjacent the passage in the conduit means through which the clear liquid component flows;

measuring means for determining the glucose level in the blood based on the detected optical property; and

regulating means for controlling the flow of liquid through the passage in the conduit means and past the optical detecting means, said regulating means including a pressure regulating member and means for connecting said pressure regulating member to the ribs of a patient, whereby the breathing activity of the patient aids in regulating the pressure in the system.

3. The system of claim 2 wherein said pressure regulating member includes a bellows, and said means for connecting the bellows to the ribs includes adjustable hook means adjacent opposed ends of said bellows.

4. A device for regulating fluid flow in a system, wherein the system is adapted to be secured to an animal, said device including control means connected to the system and movable between first and second positions for aiding in controlling fluid flow through the system, and attachment means forming part of the control means and being attachable to an internal, movable part of the animal for causing the control means to move between said first and second positions as the animal breathes.

5. The device of claim 4 wherein said attachment means includes hook means attachable to spaced-apart ribs of the animal.

6. The device of claim 4 wherein said device is adapted to be inserted inside a human body and said attachment means are adapted to be attached to adjacent ribs of said human body.

7. The device of claim 4 wherein the control means includes a bellows movable between a first expanded condition and a second compressed condition.

8. The device of claim 7 wherein said attachment means includes hook means attachable to spaced-apart ribs of the animal.

9. A method of segregating a clear liquid component of a patient'"'"'s blood from the blood cells and proteins of said blood including the steps of:

a. inserting a filter member within a blood vessel of the patient and;

b. connecting a pressure regulating device to spaced-apart ribs of the patient, whereby the breathing activity of the patient is employed to establish a pressure differential across the filter member for aiding in directing the clear liquid component of the blood through the filter member and for directing said clear liquid component out of the blood vessel to thereby separate the clear liquid component from the blood cells and proteins.

10. The method of claim 9 where the filter member is a hollow member, including the steps of filtering the clear liquid component of the blood into the hollow interior of said filter member and thereafter removing the clear liquid component from the hollow interior of said filter member to a location within the patient'"'"'s body but remote from the patient'"'"'s blood vessel.

11. In a glucose monitoring system to be employed by a patient while the patient is mobile, a microporous filter means insertable into a blood vessel of the patient for permitting a clear liquid component of the blood to be separated from the blood cells and proteins of the blood by being filtered through said filter means, said clear liquid component including the glucose to be monitored ;

and means securable to internal, movable parts of the patient'"'"'s body for establishing a pressure differential through said microporous filter means for directing the clear liquid component of the blood through said filter means.

12. The system of claim 11 wherein said microporous filter means is a hollow filter member having a continuous, microporous wall, whereby the clear liquid component of the blood is directed through said microporous wall into the hollow interior of said filter member.