COMPARATIVE STUDIES OF TRANQUILIZERS USED IN ANESTHESIA

The usefulness of certain tranquilizers in anesthesia for surgery was studied in 1159 cases. Chlorpromazine was used in 350, mepazine in 434, diphenhydramine in 182, and promethazine in 193. A mixed series of 262 patients who received either morphine or meperidine, with a belladonna derivative and with or without a barbiturate, served as a reference group. The tranquilizers were given two hours before operation, and the size of each study group was determined primarily by the number of patients required to establish a significant trend for the given tranquilizer. The effective dosage range for chlorpromazine was thus found to be 12.5 to 50 mg. intramuscularly, for mepazine 200 to 400 mg. orally, for promethazine 25 to 50 mg. intramuscularly, and for diphenhydramine 50 to 100 mg. intramuscularly. They all diminished undesirable reflex activity while causing less over-all depression than has been possible with routine doses of narcotics and barbiturates. The reduced incidence of postoperative nausea and vomiting was especially noted when chlorpromazine was used.