Methods and systems for continuously monitoring the glucose level of a patient
A device for continuously monitoring glucose levels in a patient is disclosed. The device includes a glucose electronics assembly and a glucose lead assembly in electrical communication with the glucose electronics assembly. The glucose electronics assembly is configured to be positioned in the subcutaneous tissue and the glucose lead assembly is configured to be positioned in a vessel of the patient. The glucose lead assembly has a central shaft, a first electrode in physical communication with the central shaft, a second electrode in physical communication with the central shaft, a third electrode in physical communication with the central shaft and a positioning element configured to have an undeployed state and a deployed state. In the undeployed state, the positioning element is substantially linear, and in the deployed state, the positioning element extends away from the central shaft.
1 . A device for continuously monitoring glucose levels in a patient, comprising:
an electronics assembly configured to be positioned outside a fluid-filled lumen of the patient;
a lead assembly in electrical communication with, and physically coupled to, the electronics assembly, wherein the lead assembly is configured to be positioned within the fluid-filled lumen of the patient, the lead assembly comprising:
a lead wire defined by a length and a circumference;
a working electrode, a reference electrode, and a counter electrode disposed on the lead wire, wherein the working electrode encircles the circumference of the lead wire; and
a potentiostat positioned within the electronics assembly and configured to control a voltage between the working electrode and the reference electrode, wherein the working electrode, the reference electrode, and the counter electrode collectively form an enzymatic glucose sensor that is structurally configured to maintain electrochemical glucose sensing functionality within the fluid-filled lumen for a continuous implantation period of at least 12 months.
2 . The device of claim 1 , wherein a combined surface area of the reference electrode and the counter electrode is at least 1.5 times greater than a surface area of the working electrode.
3 . The device of claim 1 , wherein a surface area of the working electrode is at least 10 mm 2 .
4 . The device of claim 1 , wherein the length of the lead wire is between 1 centimeter and 20 centimeters.
5 . The device of claim 1 , wherein the fluid-filled lumen comprises a central venous vasculature, a peripheral venous vasculature, or a spinal column.
6 . The device of claim 1 , wherein a structure of at least one of the working electrode, the counter electrode, and the reference electrode comprises one or more of a coil, a ring, and a paddle.
7 . The device of claim 1 , wherein at least one of the working electrode, the counter electrode, and the reference electrode comprises one or more of platinum, silver-silver chloride, and iridium oxide.
8 . The device of claim 1 , wherein the reference electrode comprises one or more of platinum, iridium, and a noble metal alloy.
9 . The device of claim 1 , wherein at least one of the working electrode, the counter electrode, and the reference electrode comprises one or more bioresorbable membranes.
10 . The device of claim 1 , wherein the electronics assembly comprises an analog to digital converter, a power source, a digital communication circuit, and a microcontroller.
11 . The device of claim 1 , wherein the electronics assembly is configured to interface wirelessly with an external computing device.
12 . A method for continuously monitoring, in-vivo, glucose levels in a patient, comprising:
positioning, within a fluid-filled lumen of the patient, a lead assembly comprising a lead wire having a distal end and a proximal end and defined by a length and a circumference and a working electrode, a reference electrode, and a counter electrode disposed on the lead wire, wherein the working electrode encircles the circumference of the lead wire and wherein the electrodes collectively form an enzymatic glucose sensor; and
delivering a voltage bias to the working electrode and the reference electrode using a potentiostat that is part of an electronics assembly physically attached to the lead assembly and positioned outside the fluid-filled lumen of the patient; and
maintaining enzymatic electrochemical glucose sensing by the electrodes within the fluid-filled lumen over a continuous implantation period of at least 12 months as a result of the structural configuration of the enzymatic glucose sensor.
13 . The device of claim 12 , wherein the length of the lead wire is between 1 centimeter and 20 centimeters.
14 . The method of claim 12 , wherein the fluid-filled lumen comprises a central venous vasculature, a peripheral venous vasculature, or a spinal column.
15 . The method of claim 12 , wherein a combined surface area of the reference electrode and the counter electrode is at least 1.5 times greater than a surface area of the working electrode.
16 . The method of claim 12 , wherein a structure of at least one of the working electrode, the counter electrode, and the reference electrode comprises one or more of a coil, a ring, and a paddle.
17 . The method of claim 12 , wherein at least one of the working electrode, the counter electrode, and the reference electrode comprises one or more of platinum, silver-silver chloride, and iridium oxide.
18 . The device of claim 12 , wherein the reference electrode comprises one or more of platinum, iridium, and a noble metal alloy.
19 . The method of claim 12 , wherein at least one of the working electrode, the counter electrode, and the reference electrode comprises one or more bioresorbable membranes.
20 . The method of claim 12 , wherein the electronics assembly comprises an analog to digital converter, a power source, a digital communication circuit, and a microcontroller.
21 . The method of claim 12 , wherein the electronics assembly is configured to interface wirelessly with an external computing device.