title: Infrared tympanic thermometry in a hot environment.
abstract: The purpose of this study was to compare tympanic (measured by infrared thermometry; Tty- (IRED)) with rectal and esophageal temperatures (T(REC) and T(ES)) during exercise in the heat. During Experiment 1, nine subjects pedaled for 55 min in a hot-dry environment (37 degrees C; 27% humidity) in still-air (<0.2 m/s) and for 10 additional min using water ingestion, wind and ice to cool them down. During Experiment 2, subjects pedaled for 90 min in a similar environment but with airflow at 2.5 m/s. Pearson correlation coefficients (r) and Bland-Altman plots were calculated. In Experiment 1, Tty-(IRED) and T (REC) were highly correlated (r=0.83; p<0.001) with close agreement (-0.08+/-0.4 degrees C). Overall Tty-(IRED) was significantly correlated with T(ES) (r=0.91; p<0.001). Cold water ingestion did not affect Tty-(IRED) or T(REC) but lowered T(ES). Wind and ice application lowered Tty- (IRED) below T(REC) (p<0.05). During Experiment 2, Tty-(IRED) was lower than T(REC) (p<0.05) and the difference increased throughout exercise as hyperthermia developed resulting in low agreement (-1.01+/-1.1 degrees C). In conclusion, Tty- (IRED) dangerously underestimates T(REC) when exercising in a hot environment with airflow or during a cooling treatment. However, it could correctly detect hyperthermia during exercise in a hot still-air environment.
authors.affiliation: Facultad de Ciencias del Deporte, Universidad de Castilla-La Mancha, Toledo, Spain.
authors.forename: J D
authors.initials: JD
authors.lastname: Coso
authors.forename: R
authors.initials: R
authors.lastname: Aguado-Jimenez
authors.forename: R
authors.initials: R
authors.lastname: Mora-Rodriguez
mesh_terms: D000328:Adult; D001833:Body Temperature Regulation; D004947:Esophagus; D015444:Exercise / Q000502:physiology*; D005260:Female; D005334:Fever / Q000175:diagnosis; D006358:Hot Temperature; D006801:Humans; D007259:Infrared Rays; D008297:Male; D012007:Rectum; D015203:Reproducibility of Results; D012881:Skin Temperature; D013821:Thermometers; D014432:Tympanic Membrane