title: Infrared thermometry in the diagnosis and treatment of heat exhaustion.
abstract: Infrared (IR) thermometers (FirstTemp 2000A, Intelligent Medical Systems, California) were used to monitor tympanic temperature (Tty) in 12 collapsed fun-runners suspected of suffering exertion-induced heat exhaustion (EIHE). Rectal temperature (Tre) was monitored via digital clinical thermometers. Conditions during the fun-run and in the field treatment centre were cool (air temperature 16-18 degrees C, relative humidity 60-65%). On admission, Tty was (mean +/- SEM) 1.2 +/- 0.3 degrees C lower than Tre. For admission plus subsequent monitoring data pooled, although Tty correlated significantly with Tre (r = 0.86, p < 0.001), mean Tty (37.4 +/- 0.2 degrees C) was significantly lower (p < 0.01) than mean Tre (38.4 +/- 0.4 degrees C). Cotton wool ear pads, applied to 10 of the runners on admission to minimise environmental effects on Tty, did not significantly improve the IR monitoring. A Tty > or = 37.1 degrees C predicted a Tre > or = 38 degrees C (an established diagnostic criterion for EIHE) with a sensitivity of 0.93 and a specificity of 0.63. These data indicate that IR tympanic thermometry, when utilised in cool environments, can result in misdiagnosis of heat exhaustion. Although IR thermometry shows some promise as a rapid, non-invasive means of monitoring core temperature, it should not be used in the diagnosis and treatment of heat exhaustion unless further research validates the method.
authors.affiliation: Department of Life Sciences, University of Sydney.
authors.forename: R D
authors.initials: RD
authors.lastname: Hansen
authors.forename: T S
authors.initials: TS
authors.lastname: Olds
authors.forename: D A
authors.initials: DA
authors.lastname: Richards
authors.forename: C R
authors.initials: CR
authors.lastname: Richards
authors.forename: B
authors.initials: B
authors.lastname: Leelarthaepin
mesh_terms: D000328:Adult; D015444:Exercise / Q000502:physiology; D005260:Female; D006359:Heat Exhaustion / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D008297:Male; D012420:Running / Q000502:physiology; D013817:Thermography; D014432:Tympanic Membrane