title: Estimating core temperature with external devices after exertional heat stress in thermal protective clothing.
abstract: BACKGROUND
  Temperature measurement is important for emergency medical services (EMS) providers when identifying and treating heat illness or infection. Direct measures of body core temperature (T(c)) are often expensive (ingestible capsules) or impractical (rectal probes) in the field. Multiple devices for estimating T(c) have been adopted by EMS providers, with little understanding of the agreement between these devices and T(c).
  
  
  OBJECTIVE
  To examine the agreement between the results of five external thermometers and T(c) after subjects experienced physical exertion while wearing protective clothing.
  
  
  METHODS
  Fifty firefighters completed treadmill walking in thermal protective clothing in a hot environment. Measurements of core, temporal, tympanic, forehead, and skin temperatures were obtained during a 20-minute recovery period simulating emergency incident rehabilitation.
  
  
  RESULTS
  The mean bias of external thermometers ranged from -1.31°C to -3.28°C when compared with T(c) and exceeded the predetermined clinical cutoff of ±0.5°C from T(c). The 95% limits of agreement ranged from 2.75°C to 5.00°C.
  
  
  CONCLUSIONS
  External measuring devices failed to accurately predict T(c) in hyperthermic individuals following exertion. Confidence intervals around the bias were too large to allow for reasonable estimation of T(c). EMS providers should exercise caution when using any of these temperature estimation techniques.
authors.affiliation: Department of Emergency Medicine, Emergency Responder Human Performance Laboratory, University of Pittsburgh, 3600 Forbes Avenue, Suite 400A, Pittsburgh, PA 15261, USA.
authors.forename: Riana R
authors.initials: RR
authors.lastname: Pryor
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Seitz
authors.forename: Julia
authors.initials: J
authors.lastname: Morley
authors.forename: Joe
authors.initials: J
authors.lastname: Suyama
authors.forename: Francis X
authors.initials: FX
authors.lastname: Guyette
authors.forename: Steven E
authors.initials: SE
authors.lastname: Reis
authors.forename: David
authors.initials: D
authors.lastname: Hostler
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001831:Body Temperature; D019719:Diagnostic Equipment; D004632:Emergency Medical Services; D005080:Exercise Test; D005260:Female; D005334:Fever / Q000175:diagnosis*; D005390:Fires; D006358:Hot Temperature / Q000009:adverse effects*; D006801:Humans; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects; D005082:Physical Exertion; D011481:Protective Clothing / Q000009:adverse effects*; D055815:Young Adult