REVIEW ON CYANIDE POISONING

Cyanide is one of the most lethal poison. It leads to death within a few minutes to a few hours sometimes. Depending upon the dose and route of administration or exposure the symptoms develop. The area of exposure is manufacturing and industrial sources such as insecticides, photographic solution, fumigation and electroplating work, plastic manufacturing and jewelry cleaners etc. History shows the common use of cyanide poisoning in suicidal and homicidal cases and also use as chemical warfare agent for terrorist attack. Incidence of cyanide poisoning is rare but the occurrence of death is seen instant in some cases. It causes histotoxic anoxia and inhibits oxidative phosphorylation, a process where oxygen is utilized for the production of essential cellular energy sources in the form of ATP. It does so by binds to the enzyme cytochrome C oxidase and blocks mitochondrial transport chain. This results in cellular hypoxia and the depletion of ATP occur, leading to metabolic acidosis. Symptoms such as headache, dizziness, vertigo, spasmodic closure of jaw and clawing of hands, tonic type of convulsions of the limb and trunk, muscular weakness and flaccidity, muscular paralysis, intense cyanosis, hypertension followed by hypotension, coma etc leads to death. Death is mainly due to cardiovascular failure and respiratory failure. Thus, rapid treatment to be started in such patients. The 100 % oxygen support and rapid therapy of antidotal treatment is necessary for life saving. Very efficient antidote is Hydroxocobalamin and other antidotes are also important in cyanide poisoning in the treatment as life saver. Survivors of cyanide poisoning may develop neuropathies.