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

Vesicantstion without significant tissue injury will be able toreturn to duty. Determining the level of injury requiresobservation for 3 to 7 days. Anyone with documentedmustard lung injury producing bronchial pneumoniaor pseudomembrane formation will be unable to returnto duty for several months. Those with severe casesmay never return to duty.Skin. Only patients with small TBSA injuries (lessthan 5%) in noncritical areas will be able to return toduty following treatment with topical antibiotic, dressings,and oral analgesics. Burns to the hands, feet, face,axillae, and groin are all potentially disabling. (A recentaccident victim required hospitalization in a burn centerfor burns on the arm and leg amounting to 6% to 7%TBSA, sustaining serious disability from a relativelysmall surface area injury.) For all but the mildest ofinjuries return to duty will require weeks to months.Burns by liquid on the skin and in the eye cause themost severe injury. It is possible, however, to receive anearly total body burn with mustard vapor with effectsno more severe than those from a second-degree sunburn.Such a mild vapor burn would take 48 or morehours to develop. However, a vapor burn developingin only a few hours could be as severe as a liquid burn.Severity of a mustard burn is dependent upon the totalabsorbed dose of vapor and liquid.Long-Term EffectsMustard burns may leave areas of hypopigmentationor hyperpigmentation, sometimes with scarring.Individuals who survive an acute, single mustardexposure with few or no systemic or infectious complicationsappear to recover fully. Previous cardiopulmonarydisorders, severe or inadequately treatedbronchitis or pneumonitis, a prior history of smoking,and advanced age all appear to contribute to long-termchronic bronchitis; there is no definitive way to determinewhether these conditions are the result of aging,smoking, or a previous mustard exposure. Casualtieswith severe airway lesions may later have postrecoveryscarring and stenosis, which predispose the individualto bronchiectasis and recurrent pneumonia. 59An important late sequela of mustard inhalation is atracheal/bronchial stenosis that necessitates bronchoscopyand possible dilatation, isotonic saline lavages,laser surgery, or silicone stents. 235 Mustard has been reportedto create a long-term sensitivity to smoke, dust,and similar airborne particles, probably as a result ofclinically inapparent bronchospasm. 59,240The relationship between mustard exposure andsubsequent cancer has been the subject of much study.It seems clear that individuals who were exposed tomustard daily for long periods (eg, workers in mustardproduction plants) have a slightly higher incidence ofcancer of the airways, primarily the upper airways. 241–243According to two separate reports, the associationof one or two exposures on the battlefield with subsequentcancer is not clear; in a third report, the relationbetween mustard exposure and subsequent cancer isequivocal. 244–246 Watson and associates reviewed themustard exposure–cancer incidence relation in 1989,concluding that the maximum estimates of lifetimecancer risks with sulfur mustard are not great, butneither are they entirely negligible. 247In 1991 the National Academy of Sciences appointeda committee to survey the health effects of mustardand lewisite. 246 Veterans of World War II who had beenexposed to mustard and lewisite as subjects in testprograms were presenting at Veterans Administrationhospitals with complaints of illnesses they believed tobe associated with the exposures. The committee wasrequested to survey the literature to assess the strengthof association between these chemical agents andthe development of specific diseases. The committeereported finding a causal relationship between exposureand various cancers and chronic diseases of therespiratory system; cancer and certain other problemsof the skin; certain chronic eye conditions; psychologicaldisorders; and sexual dysfunction. They foundinsufficient evidence for a causal relationship betweenexposure and gastrointestinal diseases, hematologicaldiseases, neurological diseases, and cardiovasculardiseases (except those resulting from infection followingexposure). Some of these conclusions were notwell supported. For example, there were no cases ofskin cancer reported, and the alleged psychologicaldisorders were from the trauma of exposure, not fromthe agent (see Chapter 9, Long-Term Health Effects ofChemical Threat Agents).LEWISITELewisite (b-chlorovinyldichloroarsine), an arsenicalvesicant, is of secondary importance in the vesicantgroup of agents. It was synthesized in the early 20thcentury and has seen little or no battlefield use. 248Lewisite is similar to mustard in that it damages theskin, eyes, and airways; however, it differs from mustardbecause its clinical effects appear within secondsof exposure. An antidote, British antilewisite (BAL[dimercaprol]), can ameliorate the effects of lewisite ifused soon after exposure. For use as a chemical warfareagent, lewisite has some advantages over mustard butalso some disadvantages.291