Cardiovascular effects of procaine and lidocaine (xylocaine) during general anesthesia

The cardiovascular effects of intravenous procaine and lidocaine were compared in two series of patients under nitrous-oxide-thiobarbiturate anesthesia. The arterial blood pressure and electrocardiogram of these patients were continuously monitored while standarized doses of 2.2 mg/kg and 1.1 mg/kg of the test drug were administered. It was found that procaine administration was followed by cardiovascular depression in 50 % of the doses administered, while a blood pressure increase was noted following 47 % of the lidocaine injections. The lack of vasomotor depression with the administration of lidocaine is advantageous when this agent is used to supplement general anesthesia.