Induction of general anesthesia with diazepam or thiopental: a comparison of the cardiorespiratory effects.

Detailed cardiorespiratory studies were performed in 10 volunteers in whom general anesthesia was induced with thiopental 3 mg/kg and diazepam 0.4 mg/kg.Minimal changes in blood pressure were noted with both agents. Depression of total peripheral resistance lasted in excess of 20 minutes with diazepam but had returned to control levels with thiopental, elevations in cardiac rate and output were most evident and lasted longer with diazepam. In the healthy volunteer induction of anesthesia with diazepam causes alterations in cardiovascular parameters which are more profound than with thiopental. The data presented is in contrast to that obtained when patients with cariovascular disease are studied.With diazepam, considerable individual variation and long recovery times were confirmed.Following extensive clinical use, a detailed study demonstrated minimal cardiovascular depression following intravenous induction of sedation with diazepam, in patients who had prior cardiovascular disease. Subsequent studies suggested that diazepam would be a more suitable alternative for induction of general anesthesia in patients with cardiovascular disease. This was confirmed by Ikram and Rubin. It has been used extensively for sedative techniques in dentistry, and therefore it was logical to extend this concept to the induction of general anesthesia by intravenous diazepam. It was decided to evaluate the use of intravenous diazepam for induction of general anesthesia and to compare the detailed cardiovascular and respiratory effects of this drug with thiopental.