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

Medical Aspects of Chemical Warfarerequire some form of medical care—from a few daysto many weeks. Eye care and airway care will promotehealing within weeks; skin lesions take the longest toheal and may necessitate hospitalization for months. 17Casualties with mild to moderate mustard damageneed supportive care. Pain control is extremely important.Fluids and electrolytes should be carefullymonitored. Although there is not as great a fluid lossfrom mustard burns (compared with thermal burns),patients will probably be dehydrated when they enterthe MTF. Parenteral fluid supplements and vitaminsare of benefit. Patients who have lost their eyesightbecause of mustard exposure should be reassuredthat they will recover their vision. Casualties who dobecome critically ill from their exposure to mustardpresent with large areas of burns, major pulmonarydamage, and immunosuppression. Some may die fromsepsis or from overwhelming damage to the airwaysand lungs.There are no controlled human studies comparingdifferent treatments for mustard exposure; nor haveuniform standards of care been developed. However,suggestions for the care required for each organ systemis described in the section below. Recommendationsfor skin care are based on research and experience withthermal burns. Most casualties have more than onesystem involved, and many of these casualties will bedehydrated and have other injuries as well.SkinCurrent treatments. Significant cutaneous HDinjuries can take several months to heal, necessitatelengthy hospitalizations, and result in significant cosmeticand/or functional deficits. There are currentlyno standardized or optimized methods of casualtymanagement and no specific US Food and Drug Administration(FDA) approved treatment regimensfor HD injury. Historically, blister aspiration and/orunroofing (epidermal removal), physical debridement,irrigation, topical antibiotics, and sterile dressings havebeen the main courses of action in the medical managementof cutaneous HD injuries. 106–110 Current treatmentstrategy consists of symptomatic management and isdesigned to relieve symptoms, prevent infection, andpromote healing.Decisions regarding appropriate treatment methodsmust consider the number of casualties involvedand the exposure setting. The management of a smallnumber of workers exposed to liquid HD in a laboratorysetting or while handling munitions would bedifferent from the treatment of hundreds of soldierswith vapor exposure in a far-forward environment.Before commencement of any treatment, patientclothing should be carefully removed and treated aspotentially contaminated, and the patient thoroughlydecontaminated. For a general overview of decontaminationprocedures, see Chapter 16, DecontaminationofChemical Casualites.Skin injury from HD can be considered a chemicalburn. Within military medical facilities, chemicalburn injuries would meet the criteria established bythe American Burn Association for referral to a burncenter. 111 The similarity between HD skin injury andtoxic epidermal necrosis (TEN), and between HD lunginjury and smoke inhalation injury further supportburn center referral, where the requisite expertise totreat these conditions is available. Within the militarymedical system, the designated center for the treatmentof major HD burns and other chemical burn injuriesis the US Army Institute of Surgical Research/ArmyBurn Center located at Brooke Army Medical Centerin San Antonio, Texas. 112 In the civilian sector, there are132 burn centers located in the United States. Locationsand contact information for these centers is availablethrough the American Burn Association at 1-800-548-BURN or online at www.ameriburn.org.The appearance of a superficial to moderate HD skininjury mimics that of a first- or second-degree burn,and the appearance of a deep HD injury resulting fromdirect liquid contact or secondary infection mimics thatof a full thickness or third-degree burn. On this basis,many burn care practitioners erroneously concludethat thermal and HD injuries are the same. However,direct comparisons in the literature between HD andthermal burns are scarce. Papirmeister et al noted thatdisintegration of the basal cell layer caused by thermalburns has been shown to produce an intraepidermalblister that contains fragments of the basal cell layerattached to the basal lamina, unlike the almost totallydenuded basement membrane in HD lesions. 31Also, mustard injuries take considerably longer toheal compared to similar-sized thermal or chemicalburns. A major argument against the adage “a burn isa burn” is that HD initially targets a specific cell type(epithelial basal cells), unlike a thermal burn, in whichdamage occurs first at the stratum corneum and thenprogresses downward.Since the stratum corneum is the structure largelyresponsible for barrier function, water loss rates arevery high immediately after a thermal burn (140–180g/m 2 /h in humans). 113 After a cutaneous HD injury,the stratum corneum remains intact for 2 to 3 days,after which barrier function becomes compromised byloss of sloughing epidermis or unroofing of the blister.Thus, the systemic fluid derangements and nutritionalrequirements seen in cutaneous HD injury are lessthan is seen with thermal burns. 17 The recommended278