Factors interfering with the accuracy of five blood glucose meters used in Chinese hospitals.

BACKGROUND: The prevalence of diabetes is increasing in China. Glucose control is very important in diabetic patients. The aim of this study was to compare the accuracy of five glucose meters used in Chinese hospitals with a reference method, in the absence and presence of various factors that may interfere with the meters. METHODS: Within-run precision of the meters was evaluated include Roche Accu-Chek Inform®, Abbott Precision PCx FreeStyle®, Bayer Contour®, J&J LifeScan SureStep Flexx®, and Nova Biomedical StatStrip®. The interference of hematocrit level, maltose, ascorbic acid, acetaminophen, galactose, dopamine, and uric acid were tested in three levels of blood glucose, namely low, medium, and high concentrations. Accuracy (bias) of the meters and analytical interference by various factors were evaluated by comparing results obtained in whole blood specimens with those in plasma samples of the whole blood specimens run on the reference method. Impact of oxygen tension on above five blood glucose meters was detected. RESULTS: Precision was acceptable and slightly different between meters. There were no significant differences in the measurements between the meters and the reference method. The hematocrit level significantly interfered with all meters, except StatStrip. Measurements were affected to varying degrees by different substances at different glucose levels, e.g. acetaminophen and ascorbic acid (Freestyle), maltose and galactose (FreeStyle, Accu-Chek), uric acid (FreeStyle, Bayer Contour), and dopamine (Bayer Contour). CONCLUSIONS: The measurements with the five meters showed a good correlation with the plasma hexokinase reference method, but most were affected by the hematocrit level. Some meters also showed marked interference by other substances.

Accuracy of temporal artery thermometry in neonatal intensive care infants.

PURPOSE: To determine the accuracy of temporal artery and axillary temperatures and the discomfort level of stable neonates during temperature measurement. SUBJECTS: Convenience sample of neonates between the ages of 32 and 40 weeks' gestation cared for in an isolette or crib. DESIGN: A method-comparison design was used to compare different methods for noninvasive temperature monitoring (infra-red temporal artery; axillary electronic) to core body temperatures (indwelling rectal probe). MAIN OUTCOME MEASURE: Bias and precision of test temperature devices (temporal artery; axillary). RESULTS: Bias and precision for the temporal artery and axillary devices were 0.30 ± 0.44 and 0.28 ± 0.33, respectively. Analysis of variance found significant differences between both temporal and axillary temperatures compared to rectal temperatures (P < .01). Statistical differences were small and did not represent a clinically important difference. No statistical difference was found between temporal artery and axillary temperatures (P = .81). Increases in neonate discomfort after temperature measurement were significantly greater with axillary than increases after temporal artery temperature measurement (P = .03). CONCLUSIONS: This study found that body temperature measured with the temporal artery thermometer was similar to temperatures obtained with an axillary thermometer in stable, afebrile neonates. The use of temporal artery thermometry appears to be an acceptable approach for noninvasive temperature measurement in neonates, which causes less discomfort in neonates.