The relationship between nitrous oxide conscious sedation and the hypnotic state.

To evaluate the hypothesis that inhalation of low levels of nitrous oxide-oxygen produces an altered state of consciousness similar to hypnosis, 20 subjects were given three suggestions (analgesia, compulsive behavior, and amnesia) during double-blind administration of either nitrous oxide-oxygen or oxygen. Results suggest that administration of nitrous oxide-oxygen may be of increased clinical usefulness if it is combined with careful use of suggestion.