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Protection against Cold in Prehospital Care: Evaporative Heat Loss Reduction by Wet Clothing Removal or the Addition of a Vapor Barrier—A Thermal Manikin Study

Published online by Cambridge University Press:  23 March 2012

Otto Henriksson ,
Peter Lundgren ,
Kalev Kuklane ,
Ingvar Holmér ,
Peter Naredi  and
Ulf Bjornstig
Otto Henriksson*
Affiliation:
Division of Surgery, Department of Surgery and Perioperative Sciences, Umea University, Umea, Sweden
Peter Lundgren
Affiliation:
Division of Surgery, Department of Surgery and Perioperative Sciences, Umea University, Umea, Sweden
Kalev Kuklane
Affiliation:
Thermal Environment Laboratory, Department of Design Sciences, Faculty of Engineering, Lund University, Lund, Sweden
Ingvar Holmér
Affiliation:
Thermal Environment Laboratory, Department of Design Sciences, Faculty of Engineering, Lund University, Lund, Sweden
Peter Naredi
Affiliation:
Division of Surgery, Department of Surgery and Perioperative Sciences, Umea University, Umea, Sweden
Ulf Bjornstig
Affiliation:
Division of Surgery, Department of Surgery and Perioperative Sciences, Umea University, Umea, Sweden
*
Correspondence: Otto Henriksson, MD Division of Surgery Department of Surgery and Perioperative Sciences Umea UniversitySE-901 85 Umea, Sweden E-mail: [email protected]
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Abstract

Introduction: In the prehospital care of a cold and wet person, early application of adequate insulation is of utmost importance to reduce cold stress, limit body core cooling, and prevent deterioration of the patient’s condition. Most prehospital guidelines on protection against cold recommend the removal of wet clothing prior to insulation, and some also recommend the use of a waterproof vapor barrier to reduce evaporative heat loss. However, there is little scientific evidence of the effectiveness of these measures.

Objective: Using a thermal manikin with wet clothing, this study was conducted to determine the effect of wet clothing removal or the addition of a vapor barrier on thermal insulation and evaporative heat loss using different amounts of insulation in both warm and cold ambient conditions.

Methods: A thermal manikin dressed in wet clothing was set up in accordance with the European Standard for assessing requirements of sleeping bags, modified for wet heat loss determination, and the climatic chamber was set to -15 degrees Celsius (°C) for cold conditions and +10°C for warm conditions. Three different insulation ensembles, one, two or seven woollen blankets, were chosen to provide different levels of insulation. Five different test conditions were evaluated for all three levels of insulation ensembles: (1) dry underwear; (2) dry underwear with a vapor barrier; (3) wet underwear; (4) wet underwear with a vapor barrier; and (5) no underwear. Dry and wet heat loss and thermal resistance were determined from continuous monitoring of ambient air temperature, manikin surface temperature, heat flux and evaporative mass loss rate.

Results: Independent of insulation thickness or ambient temperature, the removal of wet clothing or the addition of a vapor barrier resulted in a reduction in total heat loss of 19-42%. The absolute heat loss reduction was greater, however, and thus clinically more important in cold environments when little insulation is available. A similar reduction in total heat loss was also achieved by increasing the insulation from one to two blankets or from two to seven blankets.

Conclusion: Wet clothing removal or the addition of a vapor barrier effectively reduced evaporative heat loss and might thus be of great importance in prehospital rescue scenarios in cold environments with limited insulation available, such as in mass-casualty situations or during protracted evacuations in harsh conditions.

Keywords

Emergency Medical Servicesheat losshypothermiathermal insulationthermal manikin
Type
Original Research
Information
Prehospital and Disaster Medicine , Volume 27 , Issue 1 , February 2012 , pp. 53 - 58
Copyright
Copyright Henriksson © World Association for Disaster and Emergency Medicine 2012

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References

Danzl, DF: Accidental Hypothermia. In: Auerbach, PS (ed), Wilderness Medicine. 5th ed. Philadelphia: Mosby Elsevier, 2007, pp 125–159.CrossRefGoogle Scholar
The National Board of Health and Welfare (Socialstyrelsen), Hypothermia: Cold Injuries and Cold Water Near Drowning. 2nd ed. Stockholm: The National Board of Health and Welfare (Socialstyrelsen), 2002.Google Scholar
Tisherman, SA: Hypothermia, Cold injury and Drowning. In: Peitzman, AB (ed), The Trauma Manual. 2nd ed. Philadelphia: Lippincott Williams & Wilkins, 2002, pp 404–410.Google Scholar
Hassi, J, Mäkinen, T, Holmér, I, et al (eds): Handbok för kallt arbete (Handbook for Cold Work). Stockholm: Arbetslivsinstitutet, 2002.Google Scholar
Holmér, I: Protection Against Cold. In: Shishoo, R, Textiles in Sport. Cambridge: Woodhead Publishing Limited, 2005, pp 262–286.CrossRefGoogle Scholar
Robinson, S, Benton, G: Warmed blankets: an intervention to promote comfort to elderly hospitalized patients. Geriatr Nurs 2002;23:320–323.Google Scholar
Lundgren, P, Henriksson, O, et al: The effect of active warming in prehospital trauma care during road and air ambulance transportation – A clinical randomized trial. Scand J Trauma Resusc Emerg Med 2011; In press.CrossRefGoogle Scholar
Gentilello, LM, Jurkovich, GJ, Stark, MS, et al: Is hypothermia in the victim of major trauma protective or harmful? A randomized, prospective study. Ann Surg 1997;226(4):439–447.Google Scholar
Tisherman, S.A: Hypothermia and injury. Curr Opin Crit Care 2004;10:512–519.CrossRefGoogle ScholarPubMed
Wang, HE, Callaway, CW, Peitzman, AB, et al: Admission hypothermia and outcome after major trauma. Critical Care Medicine 2005;33(6):1296–1301.Google Scholar
Shafi, S, Elliott, AC, Gentilello, L: Is hypothermia simply a marker of shock and injury severity or an independent risk factor for mortality in trauma patients? Analysis of a large national trauma registry. J Trauma 2005;59(5):1081–1085.Google Scholar
Martin, RS, Kilgo, PD, Miller, PR, et al: Injury associated hypothermia: an analysis of the 2004 National Trauma Data Bank. Shock 2005;24(2):114–118.Google Scholar
Beilman, GJ, Blondet, JJ, Nelson, TR, et al: Early hypothermia in severely injured trauma patients is a significant risk factor for multiple organ dysfunction syndrome but not mortality. Ann Surg 2009;249(5):845–850.CrossRefGoogle Scholar
Ireland, S, Endacott, R, Cameron, P, et al: The incidence and significance of accidental hypothermia in major trauma – A prospective observational study. Resuscitation 2011;82(3):300–306.CrossRefGoogle ScholarPubMed
Mills, WJ: Field care of the hypothermic patient. Int J Sports Med 1992;13 Suppl 1:S199–202.Google Scholar
Giesbrecht, GG (ed): Hypothermia, Frostbite and Other Cold Injuries: Prevention, Survival, Rescue and Treatment. 2d ed. Seattle, WA: Mountaineers Books, 2006.Google Scholar
Haventih, G, Richards, MG, Wang, X, et al: Apparent latent heat of evaporation from clothing: attenuation and “heat pipe” effects. J Appl Physiol 2008;104(1):142–149.Google Scholar
Meinander, H: Influence of sweating and ambient temperature on the thermal properties of clothing. Paper presented at: Fifth International Symposium on Performance of Protective Clothing Improvement through Innovation; 25–27 January 1994; San Francisco, California, USA.Google Scholar
Meinander, H: Thermal insulation measurements of cold protective clothing using thermal manikins. SUBZERO project, final report. Tampere, Finland: Fibre Materials Science, Tampere University of Technology; 2003. Report No. 4:2003.Google Scholar
EN 13537:2002. Requirements for sleeping bags. Brussels: European Committee for Standardization.Google Scholar
EN ISO 9920:2003. Ergonomics of the thermal environment - Estimation of thermal insulation and water vapor resistance of a clothing ensemble. Geneva: International Standards Organization.Google Scholar
EN ISO 15831:2004. Clothing - Physiological effects - Measurement of thermal insulation by means of a thermal manikin. Geneva: International Standards Organization.Google Scholar
ASTM F 2370. Standard Test Method for Measuring the Evaporative Resistance of Clothing Using a Sweating Manikin. American Society for Testing and Materials, USA, 2010.Google Scholar
Anttonen, H, Niskanen, J, Meinander, H, et al: Thermal manikin measurements – Exact or not (Subzero project)? Int J Occup Saf Ergon 2004;10(3):291–300.CrossRefGoogle ScholarPubMed
Meinander, H, Anttonen, H, Bartels, V, et al: Manikin measurements versus wear trials of cold protective clothing (Subzero project). Eur J Appl Physiol 2004;92(6):619–621.Google Scholar
EN ISO 11079:2007. Ergonomics of the thermal environment - Determination and interpretation of cold stress when using required clothing insulation (IREQ) and local cooling effects. Geneva: International Standards Organization.Google Scholar
Kuklane, K, Gao, C, Holmér, I, et al: Calculation of clothing insulation by serial and parallel methods: effects on clothing choice by IREQ and thermal responses in the cold. Int J Occup Saf Ergon 2007;13(2):103–116.Google Scholar
Durrer, B, Brugger, H, Syme, D: The Medical On Site Treatment of Hypothermia. In: Elsensohn, F (ed), Consensus Guidelines on Mountain Emergency Medicine and Risk Reduction. 1st ed. Lecco, Italy: Casa Editrice Stefanoni, 2001, pp 71–75.Google Scholar
State of Alaska: Cold injuries guidelines. Available at: http://www.chems.alaska.gov/EMS/documents/AKColdInj2005.pdf. Accessed 27 August 2011.Google Scholar
Auerbach, PS, Donner, HJ, Weiss, EA: Field Guide to Wilderness Medicine. 3rd ed. Philadelphia: Mosby; 2008, pp 25–33.Google Scholar
Johnson, C, Anderson, SR, Dallimore, J, et al: Oxford Handbook of Expedition and Wilderness Medicine. Oxford: OUP Oxford, 2008, pp 596–599.Google Scholar
Lotens, WA, Havenith, G, van de Linde, FJG: Effects of condensation in clothing on heat transfer. Ergonomics 1995;38:1114–1131.Google Scholar
Havenith, G, den Hartog, E, Heus, R: Moisture accumulation in sleeping bags at -7 degrees C and -20 degrees C in relation to cover material and method of use. Ergonomics 2004; 47(13):1424–1431.Google Scholar
Wang, F, Kuklane, K, Gao, C, et al: A study on evaporative resistances of two skins designed for thermal manikin Tore under different environmental conditions. J Fiber Bioeng Inform 2009;1:301–306.Google Scholar
Kuklane, K, Heidmets, S, Johansson, T: Improving thermal comfort in an orthopaedic aid: better Boston Brace for scoliosis patients. Paper presented at: The 6th International Thermal Manikin and Modelling Meeting (6I3M), 16–18 October 2006, The Hong Kong Polytechnic University, Hong Kong SAR.Google Scholar
Henriksson, O, Lundgren, JP, Kuklane, K, et al: Protection against cold in prehospital care – Thermal insulation properties of blankets and rescue bags in different wind conditions. Prehosp Disaster Med 2009;24(5):408–415.CrossRefGoogle ScholarPubMed