Carbamate poisoning: treatment recommendations in the setting of a mass casualties event

The threat of using chemical compounds by terrorists as weapons of mass casualties has been a rising concern in recent years. Carbamates, a group of reversible acetylcholinesterase inhibitors, could be potentially involved in such toxic mass casualty events because they can cause cholinergic crisis that could lead to fatality, similar to that of organophosphate poisoning. The medical management of carbamate poisoning consists of supportive measures and specific antidotal treatment, that is, the anticholinergic compound atropine. The administration of oximes, acetylcholinesterase reactivators, in carbamate poisoning is controversial because of the potential toxicity of oximes in conjunction with carbamate especially in the case of the carbamate--"carbaryl" poisoning. However, recent data suggest that this concern may be unwarranted. In this article, we review the current data regarding the pros and cons of using oximes against carbamates poisoning in a mass casualties event scenario. We also propose a new decision-making algorithm for the medical first responders in a mass casualties event suspected to be caused by a cholinergic substance (organophosphate or carbamate). According to this algorithm, treatment should consist of atropine and oxime regardless of the exact toxic compound involved. We speculate that in a mass casualties event, the benefits of using oximes outweigh the low level of potential risk.