Method and apparatus for using alternative site glucose determinations to calibrate and maintain noninvasive and implantable analyzers

Abstract

A method and apparatus for calibrating noninvasive or implantable glucose analyzers uses either alternative invasive glucose determinations or noninvasive glucose determinations for calibrating noninvasive or implantable glucose analyzers. Use of an alternative invasive or noninvasive glucose determination in the calibration allows minimization of errors due to sampling methodology, and spatial and temporal variations that are built into the calibration model. An additional embodiment uses statistical correlations between noninvasive and alternative invasive glucose determinations and traditional invasive glucose determinations to adjust noninvasive or alternative invasive glucose concentrations to traditional invasive glucose concentrations. The invention provides a means for calibrating on the basis of glucose determinations that reflect the matrix observed and the variable measured by the analyzer more closely. A glucose analyzer couples an invasive fingerstick meter to a noninvasive glucose analyzer for calibration, validation, adaptation, and safety check of the calibration model embodied in the noninvasive analyzer.

Description

CROSS REFERENCE TO RELATED APPLICATION [0001] This Application is a divisional application of U.S. patent application Ser. No. 10 / 377,916, filed Feb. 28, 2003, which claims benefit of U.S. provisional patent application Ser. No. 60 / 362,899, filed Mar. 8, 2002 and U.S. provisional patent application Ser. No. 60 / 362,885, filed Mar. 8, 2002, each of which is incorporated herein in its entirety by this reference thereto.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The invention relates generally to the calibration and maintenance of glucose analyzers. More particularly, the invention relates to the use of alternative site glucose determinations to improve algorithm development, calibration, and / or quality control of noninvasive or implantable glucose analyzers. [0004] 2. Background Information [0005] Diabetes is a chronic disease that results in improper production and utilization of insulin, a hormone that facilitates glucose uptake into cells. While a precise ca...

AI Technical Summary

Benefits of technology

[0058] The invention provides a method and apparatus for using either alternative invasive glucose determinations or alternative site noninvasive glucose determinations for calibrating noninvasive or implantable glucose analyzers. Use of an alternative invasive or alternative site noninvasive glucose determination in the calibration allows for minimization of errors built into the glucose analyzer model, including errors due to sampling, methodology, and errors due to temporal and spatial variations of glucose concentration within the subject's body. In addition, the invention provides conversion of glucose concentrations determined from noninvasive or alternative reference determinations into traditional invasive glucose determinations. As described herein, the use of an alternative invasive or noninvasive glucose determination for calibration is also understood to include their use for glucose determination, prediction, calibration transfer, calibration maintenance, quality control, and quality assurance.

Problems solved by technology

Diabetes is a chronic disease that results in improper production and utilization of insulin, a hormone that facilitates glucose uptake into cells.

Diabetes is a leading cause of death and disability worldwide.

However, current monitoring techniques discourage regular use due to the inconvenient and painful nature of drawing blood through the skin prior to analysis.

Urine tests for glucose have given way to the invasive fingerstick glucose determinations that are more accurate but somewhat painful, also presenting a possible biohazard.

The development of alternative site glucose determinations has somewhat mitigated the pain aspects, but may have introduced a new difficulty as a result of temporal and spatial differences in glucose between the well perfused fingertip and the less well perfused alternative sites.

Additionally, the biohazard issue remains.

Obviously, this form of alternative invasive glucose determination while unsuitable for analysis of venous or arterial blood, may be utilized to collect capillary blood samples.

However, some of these same techniques can be applied to the skin in a fashion that draws blood.

For example, the laser poration method can result in blood droplets.

This leads to samples being collected with varying analyte and interferent concentrations.

Conversely, devices described above based upon techniques like a lancet, applied current, laser poration, or suction are referred to as either a traditional invasive or alternative invasive technique as they do not fulfill both the three hour and skin penetration parameters.

First, at least part of the device penetrates the skin.

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