EFFECT OF AMBIENT-TEMPERATURE AND HUMIDITY ON PERFORMANCE OF BLOOD-GLUCOSE METERS

The accuracy of four blood glucose meters (Accutrend, ExacTech Companion, Medisense Companion 2, and Glucometer III) was tested at temperatures ranging from 4 to 44 degrees C (control solutions) and 8 degrees C, 24 degrees C, and 36 degrees C (venous blood) and at humidities of 60 % and 80 %. Low and high temperatures resulted in a number of statistically significant changes in glucose readings with all meters. However, Accutrend, Medisense Companion 2, and Glucometer III were 100 % clinically accurate at all temperatures. With the ExacTech Companion, only 70.8 % of control solution and 55.6 % of venous blood results were clinically accurate. The main errors were: (1) cold temperatures lowered the result so that euglycaemic levels erroneously read in the hypoglycaemic range and hyperglycaemic levels gave a better than actual result and (2) hot temperatures increased the result whereby hypoglycaemic levels falsely gave a euglycaemic result. Weather conditions at which blood glucose meters may be operated can affect results and potentially lead to errors in clinical decisions.