[A comparative study of body temperature using rectal and tympanic measurement]

Abstract

Introduction: Tympanic temperature measuring is more and more used currently. We wanted to test this method's accuracy in an internal medicine service.

Methods: First, we compared rectal and tympanic temperatures in 37 consecutive patients. Tympanic temperature was assessed by two examiners. Secondly, we compared, in 32 other patients, the readings given by tympanic thermometer used in the first part, with those given by nine other tympanic thermometers used in other hospital departments.

Results: We did not find any difference between right and left auricular temperature, nor between the temperatures assessed by the two examiners. However, there was a difference between the average tympanic and rectal temperatures (36.88 degrees C +/- 0.63 vs 37.36 degrees C +/- 0.57; P < 0.001). The correlation coefficient between tympanic and rectal temperature was only 0.77. If a threshold of temperature of > or = 38 degrees C were given for fever, only 29% of febrile patients would have been detected with a tympanic thermometer (Kappa coefficient = 0.406 [0.326-0.485]). Fever was especially underestimated for high temperatures. The comparison of different tympanic thermometers gives different averages for these ten thermometers between 36.5 degrees C and 37.2 degrees C.

Conclusion: Though tympanic temperature measure is an easy method, it is not sensitive enough to detect fever.