title: Protection against cold in prehospital care: wet clothing removal or addition of a vapor barrier.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effect of wet clothing removal or the addition of a vapor barrier in shivering subjects exposed to a cold environment with only limited insulation available.
  
  
  METHODS
  Volunteer subjects (n = 8) wearing wet clothing were positioned on a spineboard in a climatic chamber (-18.5°C) and subjected to an initial 20 minutes of cooling followed by 30 minutes of 4 different insulation interventions in a crossover design: 1) 1 woolen blanket; 2) vapor barrier plus 1 woolen blanket; 3) wet clothing removal plus 1 woolen blanket; or 4) 2 woolen blankets. Metabolic rate, core body temperature, skin temperature, and heart rate were continuously monitored, and cold discomfort was evaluated at 5-minute intervals.
  
  
  RESULTS
  Wet clothing removal or the addition of a vapor barrier significantly reduced metabolic rate (mean difference ± SE; 14 ± 4.7 W/m(2)) and increased skin temperature rewarming (1.0° ± 0.2°C). Increasing the insulation rendered a similar effect. There were, however, no significant differences in core body temperature or heart rate among any of the conditions. Cold discomfort (median; interquartile range) was significantly lower with the addition of a vapor barrier (4; 2-4.75) and with 2 woolen blankets (3.5; 1.5-4) compared with 1 woolen blanket alone (5; 3.25-6).
  
  
  CONCLUSIONS
  In protracted rescue scenarios in cold environments with only limited insulation available, wet clothing removal or the use of a vapor barrier is advocated to limit the need for shivering thermogenesis and improve the patient's condition on admission to the emergency department.
authors.affiliation: Division of Surgery, Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden (Drs Henriksson, Lundgren, Naredi, and Bjornstig). Electronic address: otto.henriksson@surgery.umu.se.
authors.forename: Otto
authors.initials: O
authors.lastname: Henriksson
authors.affiliation: Division of Surgery, Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden (Drs Henriksson, Lundgren, Naredi, and Bjornstig).
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Lundgren
authors.affiliation: Thermal Environment Laboratory, Department of Design Sciences, Faculty of Engineering, Lund University, Lund, Sweden (Drs Kuklane and Holmér).
authors.forename: Kalev
authors.initials: K
authors.lastname: Kuklane
authors.affiliation: Thermal Environment Laboratory, Department of Design Sciences, Faculty of Engineering, Lund University, Lund, Sweden (Drs Kuklane and Holmér).
authors.forename: Ingvar
authors.initials: I
authors.lastname: Holmér
authors.affiliation: Laboratory for Exercise and Environmental Medicine, University of Manitoba, Winnipeg, Manitoba, Canada (Dr Giesbrecht).
authors.forename: Gordon G
authors.initials: GG
authors.lastname: Giesbrecht
authors.affiliation: Division of Surgery, Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden (Drs Henriksson, Lundgren, Naredi, and Bjornstig).
authors.forename: Peter
authors.initials: P
authors.lastname: Naredi
authors.affiliation: Division of Surgery, Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden (Drs Henriksson, Lundgren, Naredi, and Bjornstig).
authors.forename: Ulf
authors.initials: U
authors.lastname: Bjornstig
mesh_terms: D000328:Adult; D001481:Basal Metabolism; D001831:Body Temperature; D003020:Clothing; D003080:Cold Temperature / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007035:Hypothermia / Q000517:prevention & control*; D008297:Male; D017694:Rewarming; D012768:Shivering; D014661:Vasoconstriction; D055815:Young Adult
keywords: emergency medical services; heat loss; hypothermia; thermal insulation