A comparative study of rectal tympanic and axillary thermometry in febrile children under 5 years of age in Nigeria

Abstract

Background: Fever alone accounts for over 25% of paediatric emergency room consultations. Accurate determination of temperature is critical for the management of sick children by both parents and health care-providers.

Aims and Objectives: To compare simultaneous measurements of temperature measured by the rectal, axillary, and tympanic routes in children under 5 admitted to the University of Ilorin Teaching Hospital.

Methods: 400 children under 5 years of age with a rectal temperature of ≧38·0°C were recruited consecutively into the study. Rectal and axillary temperatures were measured using digital thermometers. Tympanic measurements were undertaken with an infrared tympanic thermometer. All measurements were made simultaneously and compared.

Results: Mean (SD) rectal temperature was 38·8 (0·7)°C, and mean (SD) tympanic and axillary temperatures were 38·7 (0·7)°C and 38·1 (0·7)°C, respectively. There was no significant difference between rectal and tympanic temperatures (P = 0·14), and a strong correlation was identified between values from these two sites (r = 0·91). At 91·5%, the sensitivity of tympanic thermometry in determining fever was higher than that of axillary measurements (54·0%). A mathematical relationship was demonstrated between rectal/tympanic temperatures and between rectal/axillary temperatures as follows:

Rectal temperature (°C) = 6·03+0·85 * Mean tympanic temperature (°C)

Rectal temperature (°C) = 11·7+0·71 * Axillary temperature (°C)

Conclusion: In febrile children, tympanic temperature better reflects rectal temperature than does axillary temperature; tympanic temperature should therefore be measured when there are no contra-indications for its use.

Keywords:

• Temperature
• Fever
• Tympanic
• Rectal
• Axillary

We thank the paediatric residents and nurses who assisted with recruiting the subjects and collecting the data.