Abstract

The relation of nitrous oxide analgesia to mental performance was determined in a group of normal subjects who were tested with three concentrations of nitrous oxide (20, 30 and 40% nitrous oxide in oxygen) and compressed air. It was observed that nitrous oxide produces significant analgesia in low concentrations, but that along with the analgesia there appears to be significant mental impairment. Both the degree of analgesia and the degree of mental impairment vary widely from one subject to another at the same concentration of nitrous oxide, and there is little correlation between the two effects of the drug in any given individual.