Preliminary Studies of Diabetic Decompensation Assessed with Bedside Glucose-Monitoring Techniques

Blood glucose-monitoring techniques originally developed to aid outpatient management of diabetic patients are now being used to facilitate hospital care. However, applications in hyperglycemic patients have been limited because many glucose-oxidase strips and meters respond only to glucose values ≤ 400 mg/dl. We asked if prior dilution of blood samples would permit reliable estimations. Ten consecutive decompensated diabetic patients (age 35–73, glucose 506–879, HCO₃ 12–28) had blood glucose determinations done simultaneously by the hospital laboratory and by Chemstrip bG after dilution of heparinized blood 1:2 in saline. Thirty-one samples were obtained before and during insulin therapy. Correlations with laboratory glucose values were 0.95 with strips read by Accu-Chek meter and 0.90 read visually, both P < 0.001. Average deviations from laboratory values were 7.9% with Accu-Chek and 12.9% with visual readings. Accu-Chek deviations averaged 9.6% for glucose > 700 mg/dl, and 6.9% for glucose > 400 mg/dl. Over the first hour of insulin therapy, glucose fell 150 ± 30 mg/dl by Accu-Chek, comparable to 168 ± 29 by laboratory measurement; the decrement by visual reading was 107 ± 32, not significantly different. We conclude that dilution of blood samples with glucose > 400 allows reliable estimation of elevated values by home glucose-monitoring techniques. This approach is cost-effective and provides the rapid feedback needed for the management of critically ill patients.