Medical Aspects of Chemical Warfare (2008) - The Black Vault

Decontamination of Chemical Casualtiesagents, can cause an acute and transient hypothermia. 87Individuals in wet clothing, or those who are stationary,will lose body heat more rapidly. Heat is conductedout through cool, damp clothing, 88 and wind convectionagainst wet skin also facilitates rapid body coolingand, in cooler temperatures, hypothermia. 89Those who are not medically compromised cantolerate ambient temperatures down to 65°F (18.3°C)for several minutes. Colder ambient temperatures,however, are uncomfortable and may cause shivering.Shivering, although it heats the body and is a sign ofhealthy thermoregulation, is very uncomfortable anddepletes a patient’s available energy stores.Protection for Decontamination Team MembersCold climates reduce the risk of heat injury for decontaminationteam members, but heat injury can occurif individuals wear excessive thermal undergarmentsunder their protective ensemble and fail to anticipatethe heat their bodies generate once they begin working.Cold injuries also can result if personnel sweat heavilyand then rest in the cold. Larimer 90 suggests wearinga complete uniform under protective overgarmentsin extremely cold climates to increase insulation. Thinlong underwear made of polypropylene or other materialscan wick sweat away from the body, 90 which isparticularly helpful when temperatures fall below 30°F(−1°C). Keeping active warms the body, and layeredclothing, although difficult to remove while in IPE,can be worn under a rubber protective apron. In coolconditions cotton or wool liners worn under rubbergloves help insulate workers’ hands against the cold.Teams should train at various temperatures to gain abetter understanding of the amount of layered underclothingappropriate for their work level, so that theydo not become overheated while working.A warming tent is important for decontaminationstaff to use when needed. 82 If a heated warming tent isnot available, blankets must be made available for staffin the rest area. Ideally, heated triage and treatmenttents as well as heated decontamination shelters shouldbe used in operations where cold temperatures are frequent.Available buildings can be used if the situationpermits. Heated tents and buildings will reduce bothstaff and patient exposure to the cold. If contaminatedclothing is not removed from patients before they arebrought into heated areas, these areas must be wellventilated so hazardous chemical vapors do not buildup inside the enclosed space. Ideally, patient clothingshould be removed just inside or outside the entranceto these facilities. Shelter air heaters and water heatersare available from most pop-up tent manufacturers.Other cold weather risks are dehydration and ice.In a cold environment individuals may not feel asthirsty as they would in warm weather, fail to drink thenecessary amount of water, and become dehydrated. 90Rehydration is critical for decontamination team members,and warm liquids should always be available. Atfreezing temperatures slips and falls on ice can posea real hazard to patients and decontamination teammembers, especially around decontamination shelterswhere soap and water are used. In freezing conditionsrock salt or a similar deicing material should be appliedto ice patches around shelters and along routesof travel.Protection for PatientsThe Department of the Army suggests four decontaminationmethods based on the ambient temperature(Table 16-6). 82 The closer the ambient temperature isto freezing, the more patient operations are conductedinside a heated enclosure. Regardless of the ambienttemperature, individuals who have been exposed toa known life-threatening level of chemical contaminationshould disrobe, undergo decontamination, and besheltered as soon as possible. Water heaters and decontaminationshelter air heaters make decontaminationoperations in cold temperatures possible, although 6to 20 minutes are needed to set up this equipment.IPE worn by patients should not be removed untilthe patient appears medically stable enough to undergodecontamination. Asymptomatic patients maybe left in IPE, still masked, and moved to a warm andwell-ventilated holding area, or they may have IPEremoved, be promptly decontaminated with warm water,and be moved directly to a warm holding area freeof contamination. If clothing is removed, replacementclothing or blankets must be provided. If the patientmay have been exposed to a liquid agent, clothing canbe removed and areas not covered by clothing can bedecontaminated. Thicker, layered winter clothing wornduring exposure provides more protection againstchemical agents than thin summer clothing, andthicker clothing should provide adequate protectionagainst dry particles. Once clothing removal begins,decontamination should be accomplished as quicklyas possible so that the patient can be covered againwith a blanket and moved to a warm area.If temperatures are near freezing, a dry decontaminantsuch as sand, paper towels, an M291 orM295 kit, or other absorbent material should be usedfor immediate decontamination before the patient ismoved into a warm tent or room for clothing removal.Heavily contaminated outer protective clothing shouldbe removed in a ventilated area immediately outsideor near the entrance to the heated room. Ample sup-549