Body Core Temperature Assessment in Emergency Care Departments

Background: There is concern that the values provided by devices using infrared thermometry in emergency departments (EDs) do not reflect body core temperature accurately. Objectives: Evaluation of three thermometers commonly used in the ED. Methods: Two infrared ear thermometers and an infrared forehead thermometer were evaluated using 1) the Voltcraft IRS -350 calibration device, 2) comparing temperature values to a rectal end -exercise temperature (T-RECT) of 38.1 degrees C in 12 participants, and 3) comparing temperature values to rectal temperature in 133 ED patients. Results: Calibration across the human core temperature range revealed that the ear thermometers underestimated radiant temperature by 0.77 +/- 0.39 degrees C and 1.84 +/- 0.26 degrees C, respectively, whereas the forehead thermometer overestimated radiant temperature by 0.90 +/- 0.51 degrees C. After cycling exercise, all thermometers underestimated T-RECT (0.54 +/- 0.27 degrees C and 1.03 +/- 0.48 degrees C for the ear thermometers and 1.14 +/- 0.38 degrees C for the forehead thermometer). In the ED, the ear thermometers underestimated T-RECT by 0.31 +/- 0.37 degrees C and 0.46 +/- 0.50 degrees C, whereas the forehead thermometer exhibited a nonsignificant overestimation of 0.04 +/- 0.46 degrees C. If the threshold for fever in all systems had been set to 37.5 degrees C instead of 38.0 degrees C, the sensitivity and specificity of the systems for real fever (T-RECT >= 38 degrees C) are, respectively, 71% and 96% (ear thermometer 1), 57% and 97% (ear thermometer 2), and 86% and 90% (forehead thermometer). Conclusion: We conclude that the investigated thermometers are not reliable as devices to measure radiant temperature, cannot be used to assess body core temperature during exercise, but may be used as a screening device, with 37.5 degrees C as a threshold for fever in emergency care settings. (c) 2023 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )