DILEMMAS OF LIFE AND DEATH WITH CYANIDE TOXICITY

Cyanide is one of the oldest poisons. Large doses of cyanide prevent cells from using oxygen and eventually these cells die. The heart, respiratory system and central nervous system are most susceptible to cyanide. Cyanide directly stimulates the chemo-receptors of the carotid and aortic bodies that results in hyperpnoea. Cardiac irregularities are often noted, but the heart invariably outlasts the respirations. The central origin of death is due to respiratory arrest. Hydrocyanic acid (HCN), sodium cyanide (NaCN) and potassium cyanide (KCN) or cyanogen are very potent, extremely lethal and most rapidly fatal. Poisoning with hydrocyanic acid is almost always fatal because of the low fatal dose and the rapidity with which it acts.