Accuracy of a noninvasive temporal artery thermometer for use in infants

Objectives: To assess the accuracy of a new noninvasive temporal artery (TA ) thermometer in infants; to compare the accuracy of the TA thermometer wit h that of a tympanic thermometer, using rectal thermometry as the criterion standard; and to compare the tolerability of the TA thermometer with that of the tympanic and rectal thermometers. Design: Prospective evaluation of the accuracy of TA and tympanic thermomet ry, using rectal thermometry as the criterion standard. getting: Emergency department of an urban pediatric hospital. Subjects: Convenience sample of 304 infants younger than 1 year presenting for care. Main Outcome Measures: Temperatures were measured using TA, tympanic, and r ectal thermometers for all infants. Agreement between TA or tympanic and re ctal temperatures was assessed. The sensitivity and specificity of TA or ty mpanic thermometers for detecting rectal fever were determined. Discomfort scores, using a standardized scale, were assessed by trained observers afte r each temperature measurement was made. Results: Linear regression analysis of the relation between TA and rectal t emperatures yielded a model with a slope of 0.79 (vs a slope of 0.68 for ty mpanic vs rectal temperature; P=.02) and an r of 0.83 (vs r=0.75 for tympan ic vs rectal temperature; P<.001). Among 109 patients with a rectal tempera ture of 38<degrees>C or higher, the TA thermometer had a sensitivity of 0.6 6 compared with the tympanic thermometer's sensitivity of 0.49 (P<.001). Di scomfort scores with TA thermometry were significantly lower than with rect al thermometry (P=.007). Conclusions: The TA thermometer has limited sensitivity for detecting cases of rectal fever in infants. However, the TA thermometer is more accurate t han the tympanic thermometer in infants, and it is better tolerated by infa nts than rectal thermometry.