Effects of intravenous bupivacaine on cardiovascular function and plasma catecholamine levels in humans.

The effects of the intravenous infusion of bupivacaine (2 mg/min for 3 hr) on cardiovascular function and various endocrine metabolic parameters were studied in a randomized single-blind crossover study in eight normal subjects. Bupivacaine infusion resulted in plasma concentrations about 1-2 micrograms/ml. Heart rate increased significantly from approximately 60 to 70 beats/min. Mean arterial blood pressure increased from 87 to about 100 mm Hg, and cardiac output decreased about 20%, both of these statistically significant. Oxygen consumption did not change significantly. Plasma epinephrine concentrations increased significantly from 0.03 to 0.08 ng/ml, but plasma norepinephrine levels did not change significantly, nor did blood concentrations of glucose, lactate and plasma cortisol, and free fatty acids. These results demonstrate that systematically administered bupivacaine results in plasma concentrations of bupivacaine comparable to those that may be observed during regional anesthesia, including a positive chronotropic and an arterial vasoconstrictive effect. These effects are probably caused mainly by a direct effect of bupivacaine on the cardiovascular system, because only quantitatively minor changes in plasma catecholamines and other endocrine metabolic parameters were observed.