Acute organophosphate poisoning: insecticides and nerve agents.

Objective: To review clinical and therapeutic bases of an organophosphate p oisoning, either with insecticide or nerve agent. Data sources: References were obtained from computerized bibliographic rese arch (Medline(R)), from personal data (academic memoir, documents under app robation of the National Defense Office), from Internet's data. Data synthesis: Generally, organophosphate poisoning occurs during accident al exposure with agricultural insecticide or suicide. The effects of organo phosphate compounds are due to the inhibition of the enzyme acetylcholinest erase. The intoxication symptoms can be divided into muscarine-like, nicoti ne-like effects, effects on the central nervous system and symptoms related to the dysfunction of the neuromuscular junction. The interest of biologic al acetylcholinesterase's measuring is minimal because it is weakly specifi c or sensitive. The immediate severity is due to hypoxia. Respiratory failu re results from the lack of central drive inflated with excessive bronchial secretions, bronchospasm and respiratory muscles paralysis. The secondary complications are early myopathies whose gravity is correlated with the dec rease of acetylcholinesterases, or later neuropathies induced by a differen t mechanism. Beside the symptomatic mesures, atropine is the specific antic holinergic treatment. When promptly used, oximes can regenerate cholinester ases. The attempted effects of the treatment are mouth dryness, pupilar dil atation and flushing of the skin. Nerve agents are lethal toxics which have a short onset time and produce severe neurological pathology. In a terrori st incident, it is as important to identify rapidly the toxic agent and pro vide emergency decontamination as to manage medical care. An effective resp onse must be multidisciplinary, involving clinicians, toxicologists, Emerge ncy Medical Service and public's health personnel. (C) 2000 Editions scient ifiques et medicales Elsevier SAS.