title: Homemade thermometry instruments in the field.
abstract: OBJECTIVE
  Esophageal temperature is the gold standard for in-the-field temperature monitoring in hypothermic victims with cardiac arrest. For practical reasons, some mountain rescue teams use homemade esophageal thermometers to measure esophageal temperature; these consist of nonmedical inside/outside temperature monitoring instruments that have been modified to allow for esophageal insertion. We planned a study to determine the accuracy of such thermometers.
  
  
  METHODS
  Two of the same model of digital cabled indoor/outdoor thermometer were modified and tested in comparison with a reference thermometer. The thermometers were tested in a water bath at different temperatures between 10°C and 35.2°C. Three hundred measurements were taken with each thermometer.
  
  
  RESULTS
  Our experimental study showed that both homemade thermometers provided a good correlation and a clinically acceptable agreement in comparison with the reference thermometer. Measurements were within 0.5°C in comparison with the reference thermometer 97.5% of the time.
  
  
  CONCLUSIONS
  The homemade thermometers performed well in vitro, in comparison with a reference thermometer. However, because these devices in their original form are not designed for clinical use, their use should be restricted to situations when the use of a conventional esophageal thermometer is impossible.
authors.affiliation: Emergency Service, University Hospital Center, Lausanne, Switzerland. mathieu.pasquier@chuv.ch
authors.forename: Mathieu
authors.initials: M
authors.lastname: Pasquier
authors.forename: Valentin
authors.initials: V
authors.lastname: Rousson
authors.forename: Grégoire
authors.initials: G
authors.lastname: Zen Ruffinen
authors.forename: Olivier
authors.initials: O
authors.lastname: Hugli
mesh_terms: D004947:Esophagus / Q000502:physiology*; D006801:Humans; D007035:Hypothermia / Q000175:diagnosis*; D013821:Thermometers / Q000592:standards*