A prospective evaluation of glucose reagent teststrips in the prehospital setting.

Reagent teststrip determination of blood glucose has been shown to be accurate for hospital and home testing and is commonly used in prehospital care despite the lack of studies in this arena. This prospective, multicenter study examines the ability of glucose reagent teststrips to detect hypoglycemia when used under field conditions compared with simultaneously drawn control samples for laboratory glucose determination. Also examined was the accuracy of the teststrips in the laboratory glucose range less than or equal to 200 mg/dL. One hundred eighty-one pairs of data were analyzed. Hypoglycemia was defined as laboratory glucose less than or equal to 60 mg/dL. The teststrips correctly identified 31 of 33 patients in this range (sensitivity = 94%), and 125 of 148 patients without hypoglycemia (specificity = 85%). The two false negative readings were 70 and 90 mg/dL. Reagent teststrips were within +/- 40 mg/dL of the laboratory value in 70% of cases. The correlation coefficient (Spearman r) between teststrip and laboratory glucose in the range less than or equal to 200 mg/dL was .80. Using teststrip readings of 90 mg/dL or less as a measure of hypoglycemia yields 100% sensitivity with a specificity of 57%. We conclude glucose reagent teststrips are a useful adjunct for use in the prehospital setting and may be valuable for the detection of hypoglycemia.