Lewisite skin effects

The rate of action of a chemical agent is the rate at which the body reacts to or is affected by that agent. The rate varies widely, even to those of similar tactical or physiological classification. For example, blister agent HD causes no immediate sensation on the skin. Skin effects usually occur several hours later (some cases result in delays of 10-12 days before symptoms appear). In contrast, lewisite produces an immediate burning sensation on the skin upon contact and blistering in about 13 h. Decontamination immediately (within 4-5 min) will prevent serious blister agent effects. 

Medical personnel should follow the same principles for managing Lewisite skin, eye, and airway lesions that they follow for managing mustard lesions. A specific antidote, BAL (dimercaprol), will prevent or greatly decrease the severity of skin and eye lesions if applied topically within minutes after the exposure and decontamination (however, preparations of BAL for use in the eyes and on the skin are no longer available). Given intramuscularly, BAL will reduce the severity of systemic effects. BAL binds to the arsenic of... 

Although Lewisite has been sporadically used in the past, very little data from human exposure exist at this time. Consequently, much of what we know in the West about Lewisite s effects mostly comes from animal experimentation. Older data from the 1930s includes observing the effects of Lewisite on a human volunteer In this case. Lewisite was completely absorbed in 5 minutes with a slight burning sensation, while mustard required from 20 to 30 minutes for absorption and produced no noticeable sensation. With Lewisite, the skin commences to redden at the end of 30 minutes then the erythema increases and spreads rapidly. It occupies a surface of 12 by 15 centimeters toward the end of the third hour.22... 

Lewisite (also known as Agent L), is no longer considered a state-of-the-art CW agent. Lewisite is a significant threat to unprotected personnel and causes prompt incapacitation from eye injuries and respiratory irritation, coupled with long-term incapacitation from skin bums, pulmonary injury, and systemic illness. Its decomposition products are toxic, making decontamination difficult. Munitions containing lewisite may contain toxic stabilizers. Lewisite is effective as vapor, aerosol, or liquid (Sidell et al., 1997). 

Tissue damage occurs within minutes of exposure to vesicants, but clinical effects may not appear for up to 24 hours. Mixtures such as HL (C03-A010) contain lewisite (C04-A002) and will produce an immediate burning sensation on contact with the skin or eyes. Some agents are rapidly absorbed through the skin and extensive skin contamination may cause systemic damage. 

Antidotes British Anti-Lewisite (BAL) can be given by intramuscular injection as an antidote for systemic effects but has no effect on the local lesions of the skin, eyes, or airways. Treatment consists primarily of supportive care. 

Treatment—Patients should be decontaminated immediately prior to treatment using the decontamination method presented in Section 7.3.2. British Anti-Lewisite (BAL) dimercaprol antidote will alleviate some effects. It is available as a solution in oil for intramuscular administration to counteract systemic effects. It is not manufactured currently in the forms of skin and eye ointments.2... 

Dimercaprol (BAL, British Anti-Lewisite) was developed in World War 11 as an antidote against vesicant organic arsenicals (B). It is able to chelate various metal ions. Dimercaprol forms a liquid, rapidly decomposing substance that is given intramuscularly in an oily vehicle. A related compound, both in terms of structure and activity, is di-mercaptopropanesulfonic acid, whose sodium salt is suitable for oral administration. Shivering, fever, and skin reactions are potential adverse effects. 

Liquid lewisite applied by eye-dropper to the forearms of men caused blanching and discoloration of the skin followed by extensive erythema within 15 to 30 minutes and vesication within 12 hours or less (Wardell, 1941, as cited in Goldman and Dacre, 1989). The pain associated with these dermal exposures reportedly occurred within two minutes and considerable discomfort persisted for about one week. Other tests with human subjects and clinical reports also indicate a similar temporal sequence of events. Exposure to lewisite vapor (0.06 to 0.33 mg/L) caused discoloration and blistering with the maximum effect occurring by 36 to 48 hours after exposure (Wardell, 1941). At a concentration of 0.01 mg/L, lewisite vapor caused inflammation of the eyes and swelling of the eyelids after 15 minutes of exposure, and inhalation of 0.5 mg/L for five minutes is considered to be potentially lethal. 

The bulk of what is known about human skin injury from SM has been gathered from victims of the mihtary use of the compoimd (Balali-Mood and Hefazi, 2006 Hefazi et al., 2006 Requena et al, 1988). Nevertheless, there are several reports where the cutaneous vesicating effects of SM were studied experimentally in human subjects (Papirmeister et al, 1991a, b Dacre and Goldman, 1996). In one comparative study (Daily et al, 1994) 12 volunteers had forearm vapor cup applications of SM, trifunctional nitrogen mustard (HNS), and lewisite. The conclusions were... 

Exposure to lewisite is very painful. Both the vapor and liquid lewisite can penetrate skin. Reddening of the skin is followed by tissue destruction (EPA, 1985a Goldman and Dacre, 1989 Pohanish, 2002 Sidell et al, 1997). Amounts as small as 0.5 ml may cause severe systemic effects and 2 ml may be lethal. Severe edema develops secondary to increased capillary permeability. Dermal bums are deeper than those seen with mustard gas and are quicker to appear (Goldman and Dacre, 1989 Sidell et al, 1997). 

A chelator should be given if there is dyspnea, pulmonary edema, or skin bums larger than pahn size (Goldfrank et al, 2002). BAL is the traditional arsenic chelator, but it has numerous side effects. The deep intramuscular injections are very painful and BAL can cause hypertension, tachycardia, and vomiting. 2,3-Dimercaptosuccinic acid (DMSA, Succimer ) can also be used to chelate arsenic (Graziano et al, 1978). 2,3-Dimercapto-l-propanesulfonic acid (DMPS) is used in Europe and has been effective in protecting rabbits from the lethal effects of lewisite (Aposhian et al, 1982). 

Inns et al. (1990) had also determined the LD50 of i.v. lewisite administration at 1.8 mg/kg (1.6-2.1 mg/kg 95% confidence interval). Thus, it can be concluded that by exposing 2 cm of rabbit skin to a dose of 5.3 mg/kg for 6 h, a dose producing the equivalent effect of 1.8 mg/kg is absorbed. No further calculations that might exaggerate the reliabihty of available data shall be conducted here. 

Lewisite, a vesicant with HD-Uke properties, causes a similar constellation of signs and symptoms involving the skin, eyes, and airways as well as systemic effects (e.g. increased capillary permeability) after absorption. However, it does not produce immunological suppression like mustard. Another difference is that the management of lewisite toxicity includes an antidote, British Anti-Lewisite (BAL) (Yue/u/.,2003). 

Lewisite Shock Pulmonary injury Blisters Decontamination soap, water, no bleach Antidote BAL-dimercaprol may decrease systemic effects of lewisite Pulmonary management BAL 3-5 mg/kg deep IM q4 h X 4 doses (dose depends on severity of exposure and symptoms) Skin management BAL ointment Eye management BAL ophthalmic ointment... 

The long-term effects of lewisite exposure do not include extensive skin burning as is seen with the mustard agents, but chronic respiratory disease may... 

British antilewisite (BAL) or dimercaprol was developed as an antidote for lewisite. It is used in medicine as a chelating agent for heavy metals. Although BAL can cause toxicity itself, evidence suggests that BAL in oil administered intramuscularly will reduce the systemic effects of lewisite. BAL skin and ophthalmic ointment decrease the severity of skin and eye lesions when applied immediately after early decontamination, but neither of these ointments is currently manufactured. 

The clinical effects of lewisite are similar to those of mustard. However, unlike mustard, lewisite liquid or vapor produces irritation and pain upon contact. As with mustard, immediate decontamination will limit lewisite s damage to skin or eyes. A specific antidote for the systemic effects of the agent exists in the form of British Anti-Lewisite (BAL). BAL must be used under medical supervision owing to its own toxic properties. There is no need to have this antidote far forward, and it can be kept in modest quantities because of the minimum threat from lewisite. 

The second exception is that while an antidote is available for systemic effects of Lewisite exposure, there are no antidotes for nitrogen mustard or sulfur mustard toxicity, with one minor caveat if given within minutes after exposure, intravenous sodium thiosulfate may prevent death due to sulfur mustard exposure (25). Otherwise, the medical management for skin, ocular, and respiratory exposure is only supportive. One guideline physicians can follow is to keep skin, eye, and airway lesions free from infection. 

No antidote is available for treatment of the sulfur component of Sulfur/ Arsenical Vesicants. BAL (Brihsh-Anti-Lewisite, dimercaprol) will alleviate some effects of the arsenical component. BAL is available as a soluhon in oil for intramuscular administration to counteract systemic effects. BAL skin ointment and BAL ophthalmic ointment are not currently manufactured. 

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