Comparison of Axillary and Infrared Tympanic Membrane Thermometry in a Pediatric Oncology Outpatient Setting

Abstract

The purpose of this study was to determine whether infrared tympanic membrane thermometry can replace mercury-in-glass temperatures as an assessment tool for detecting fevers earlier and more reliably in a pediatric oncology outpatient setting. A total of 313 patient visits had infrared tympanic temperatures (obtained by using the LighTouch LTX Pedi-Q thermometer (Exergen; Watertown, MA) and axillary temperatures taken simultaneously (obtained by using mercury-in-glass thermometers). Those patients with a normal axillary temperature and an elevated tympanic measurement of 38°C or higher had a follow-up axillary temperature conducted that evening to determine whether an elevated tympanic temperature predicted on coming fever or infection. The mean tympanic temperature was 37.5°C and the mean axillary temperature was 36.8°C, a difference of 0.7°C (P = .0001). Sixty-two (20%) patients had discrepant temperatures with a febrile tympanic and normal axillary measurement. Three (5%) of these patients were febrile at their follow-up axillary reading. Tympanic thermometry resulted in a signigcantly higher temperature reading than the axillary method. Elevated tympanic temperatures were not predictive of oncoming fever or infection. Fevers were not missed when using the tympanic method. To prevent unnecessary medical intervention, it is recommended that mercury-in-glass thermometers verify elevated tympanic temperatures.