Prevention in rats of narcosis produced by inert gases at high pressures

¹ Royal Naval Physiological Laboratory, Alverstoke, Hants., England

A technique is described for quantitative evaluation of inert gas narcosis in animals. The response of 46 adult Wistar rats to minimal electroshock was used in 102 experiments to determine the narcotic effect of nitrogen at 12.6 and 13.5 atm abs and argon at 12.6 atm abs, before and after the oral, intraperitoneal, and intravenous administration of alpha-(4-piperidyl)benzhydrol hydrochloride. The drug controlled the narcotic effect produced by these inert gases at pressure without, so far as could be observed, the occurrence of undesirable side effects. The effective dose was 40 mg (130–150 mg/kg body wt). Lower doses were only partially effective. The maximum protective action of the drug was some 48 hr after its administration.

Key Words: nitrogen • argon • alpha-(4-piperidyl)benzhydrol hydrochloride • depth intoxication

Submitted on November 2, 1962