Canadian Journal of Anesthesia, Vol 23, 395-403, Copyright © 1976 by Canadian Anesthesiologists' Society

The Cardiovascular Effects of Diazepam and of Diazepam and Pancuronium during Fentanyl and Oxygen Anaesthesia

¹ Department of Anesthesiology, University of Utah College of Medicine, 50 North Medical Drive, Salt Lake City, Utah, 84132

The cardiovascular effects of diazepam 0.5 and 1.0 mg/kg and diazepam with pancuronium 0.1 mg/kg after fentanyl 0.5 mg/kg were determined in thirteen dogs premedicated with atropine. Fentanyl produced significant reductions in heart rate, cardiac output and arterial blood pressure. Administration of 0.5 mg/kg of diazepam after fentanyl did not significantly alter stroke volume, arterial blood pressure or peripheral vascular resistance but did increase heart rate and cardiac output. Additional diazepam did not further change the heart rate, but did reduce stroke volume, cardiac output, arterial blood pressure and peripheral vascular resistance. Administration of pancuronium after fentanyl and diazepam produced marked elevations in heart rate, cardiac output and arterial blood pressure. There was no difference in mean heart rate and cardiac output when values prior to fentanyl and those obtained three minutes following pancuronium were compared. These data demonstrate that large doses of fentanyl decrease heart rate, cardiac output and arterial blood pressure in dogs premedicated with atropine but that these changes can be partially reversed with diazepam 0.5 mg/kg and completely antagonized with pancuronium 0.1 mg/kg.