Cyanide induced changes in dynamic pulmonary mechanics in rats.

Effect of subcutaneously (s.c.) administered potassium cyanide (0.5 and 1.0 LD50) and inhalation of hydrogen cyanide (55 ppm or 60.6 mg/m3) for 30 minutes was studied on various physiological parameters related to dynamic pulmonary mechanics in anaesthetized rats. Total pulmonary phospholipid with its fractions were also estimated. Both s.c. (1.0 LD50) and inhalation exposures increased air flow, transthoracic pressure and tidal volume accompanied by significant decrease in pulmonary phospholipids. Inhalation of hydrogen cyanide also exhibited direct effect on the pulmonary cells as evidenced by decreased compliance. The study suggests that inhalation of cyanide is more injurious compared to parenteral route.