Diazepam causes no adverse cardiocirculatory effects in cardiac patients

The effects of diazepam on hemodynamic measures and catecholamine levels were studied in 25 patients before administration of any other anesthetic or analgesic agent, for coronary artery bypass graft surgery. The patients were spontaneously breathing 40% oxygen in air, and no postural changes or surgical manipulations were allowed before or during the study. Before and ten minutes after completion of the intravenous infusion of 0.4 mg/kg of diazepam over five minutes, the following hemodynamic variables were determined: direct radial artery pressure, pulmonary artery pressure, central venous pressure, cardiac output by thermodilution in triplicate via a balloon-tipped pulmonary artery catheter and electrocardiograms. Norepinephrine, epinephrine, and dopamine levels were determined by liquid chromatography. Significant (P less than 0.05) reductions in pulmonary artery systolic pressure, systolic systemic blood pressure, and epinephrine levels were observed after diazepam administration. No other hemodynamic changes were statistically significant. Thus diazepam alone caused no adverse hemodynamic or endocrine effects in cardiac surgical patients. It is concluded that the use of diazepam is not contraindicated in cardiac patients with reduced myocardial oxygen supply as a consequence of coronary sclerosis.