MULTICENTER STUDY OF OXYGEN-INSENSITIVE HAND-HELD GLUCOSE POINT-OF-CARE TESTING IN CRITICAL CARE HOSPITAL AMBULATORY PATIENTS IN THE UNITED-STATES AND CANADA

Objectives: Existing handheld glucose meters are glucose oxidase (GO)- based, Oxygen side reactions can introduce oxygen dependency, increase potential error, and limit clinical use. Our primary objectives were to: a) introduce a new glucose dehydrogenase (GD)-based electrochemica l biosensor for point-of-care testing; b) determine the oxygen-sensiti vity of GO-and GD-based electrochemical biosensor test strips; and c) evaluate the clinical performance of the new Go-based glucose meter sy stem in critical care/hospital/ambulatory patients. Design: Multicente r study sites compared glucose levels determined with GD-based biosens ors to glucose levels determined in whole brood with a perchloric acid deproteinization hexokinase reference method, One site also studied G O-based biosensors and venous plasma glucose measured with a chemistry analyzer, Biosensor test strips were used with a handheld glucose mon itoring system, Bench and clinical oxygen sensitivity, hematocrit effe ct, and precision were evaluated. Setting: The study was performed at eight U.S. medical centers and one Canadian medical center. Patients: There were 1,248 patients, Results: The GO-based biosensor was oxygen sensitive. The new GD-based biosensor was oxygen-insensitive. GD-based bio sensor performance was acceptable: 2,104 (96.1%) of 2,189 glucose meter measurements were within +/-15 mg/dL (+/-0.83 mmol/L) for gluco se revels of less than or equal to 100 mg/dL (less than or equal to 5. 55 mmol/L) or within +/-15% for glucose levels of >100 mg/dL, compared with the whole-blood reference method results, With the GD-based bios ensor, the percentages of glucose measurements that were not within th e error tolerance were comparable for different specimen types and cli nical groups, Bracket predictive values were acceptable for glucose le vels used in therapeutic management, Conclusions: The performance of G D-based, oxygen-insensitive, handheld glucose testing was technically suitable for arterial specimens in critical care patients, cord blood and heelstick specimens in neonates, and capillary and venous specimen s in other patients, Multicenter findings benchmark the performance of bedside glucose testing devices, With the new +/-15 mg/dL --> 100 mg/ dL --> +/-15% accuracy criterion, point-of-care systems for handheld g lucose testing should score 95% (or better), as compared with the reco mmended reference method, Physiologic changes, preanalytical factors, confounding variables, and treatment goals must be taken into consider ation when interpreting glucose results, especially in critically ill patients, for whom arterial blood glucose measurements wilt reflect sy stemic glucose levels.