Canadian Journal of Anesthesia, Vol 19, 129-137, Copyright © 1972 by Canadian Anesthesiologists' Society

Double-Blind Evaluation of Doxepin Hydrochloride (Sinequan®) for Preanaesthetic Medication

¹ Department of Anesthesiology, state University Hospital, State University of New York, Upstate Medical Center, Syracuse, New york, 13210, U.S.A.

A double-blind evaluation of randomly-assigned placebo, secobarbital (100 mg), diazepam (10 mg) and doxepin (25 mg) was carried out in 442 consenting, adult patients who were scheduled for elective major operations under general anaesthesia. A capsule of the test compound was given orally the night before to aid induction of sleep with provision for supplementary medication with secobarbital if sleep did not occur within two hours. About one hour before induction of anaesthesia, scopolamine (0.3 or 0.4 mg) and one of the test compounds were injected intramuscularly from separate syringes. Data were collected by a specially trained nurse from the patients' records and interviews of patients and anaesthetists. Upon completion of the study, all pertient information was punched on ibm cards and tabulated. The code was then revealed to allow statistical analysis by the chisquare test.

The data were found to be comparable in the four treatment groups, as to sex, age, physical state, and anaesthetic agent used. Vital signs were not affected by the medication and no adverse reactions were observed, although patients appeared to be heavily sedated in some instances. Although the over-all effects of the sedative drugs on the patients were not significantly different from those that received placebo, there were more patients with inadequate sedation in the placebo group. There was no striking difference in the effect of diazepam and doxepin, which appeared to be marginally better than secobarbital and the placebo.