Canadian Journal of Anesthesia, Vol 3, 224-234, Copyright © 1956 by Canadian Anesthesiologists' Society

Pacatal in Anaesthesia: A Preliminary Report

¹ Departments of Anaesthesia, University of Manitoba, Winnipeg General Hospital, and the Childrens' Hospital, Winnipeg

The history of the introduction of a new phenothiazine derivative into medicine has been reviewed and allusion made to the concept of ataraxic drugs.

The pharmacology of Pacatal in animals has been briefly reviewed and also the clinical findings of other investigators.

This report deals with observations made on the use of Pacatal for 352 patients undergoing surgery, 44 obstetrical patients, and other uses in 3 patients.

Doses of 100–200 mg (1 mg./lb) were found effective irrespective of the route administered.

Favourable effects noted include. good preoperative sedation, tranquillization more noticeable than hypnosis, ease of control of anaesthetic procedure (between anaesthesia and analgesia), possibility of decreased amounts of anaesthetic agents, antisecretory effects enabling the use of atropine to be avoided in adults, normal response to vasopressors, tranquil postoperative course, decreased incidence of postoperative nausea and vomiting.

The drug was relatively non-toxic to the cardiovascular and respiratory systems. Dangerous potentiation of narcotics was not seen.

Irritation at the site of injection can occur. The drug is rapidly eliminated and postoperative depression is unusual However, if anaesthetic agents (particularly Pentothal or ether) are used in moderate amounts following Pacatal administration, postoperative depression may be prolonged for two to three hours.

Further investigation of this agent is considered desirable.

Note:

A phenothiazine derivative

Presented at the meeting of the Western Divisions, Canadian Anaesthetists' Society, Vancouver, BC, April 5–7, 1956