injuries poisoning
Systemic Asphyxiant Chemical Warfare Agents
Symptoms and Signs of Systemic Asphyxiant Chemical Injuries
Cyanideinitially causes gasping, tachycardia, and hypertension. Loss of consciousness and convulsions may occur in as little as 30 seconds. Tetanus-like signs, including trismus (lockjaw), risus sardonicus (grimacing), and opisthotonus (neck arching), may occur. The skin may be flushed, but about half of casualties are cyanotic. Apnea usually precedes bradycardia and hypotension, and decorticate posturing may be noted prior to death. Hydrogen sulfidein high doses also causes abrupt loss of consciousness with convulsions. Direct damage to myocardium may be prominent. Continued exposure to initially sublethal concentrations may induce eye irritation with conjunctivitis and corneal abrasions and ulcerations (gas eye), irritation of nasal and pharyngeal mucous membranes, headache, weakness, ataxia, nausea, vomiting, chest tightness, and hyperventilation. Some of these manifestations appear to be a reaction to the offensive odor of the compound. A green discoloration or darkening of coins carried by the patient should lead to a heightened suspicion of hydrogen-sulfide poisoning. 