Cardiac dysrhythmias during outpatient dental anaesthesia with enflurane. The role of "beta blockade".

In a study of 120 unpremedicated outpatients presenting for outpatient dental anaesthesia, the incidence of dysrhythmias was lower with enflurane than had previously been found with halothane (1). The intravenous use of the cardioselective beta adrenergic blocking agents practolol and metoprolol, in a dose of 0.05-0.22 and 0.16-0.17 mg/kg body weight, respectively, proved effective in the treatment of sinus tachycardia in excess of 150 beats/min and/or ventricular dysrhythmias. Although metoprolol, unlike practolol, has no intrinsic sympathetic activity, there were no side-effects related to either beta-blocker in the dosages used during enflurane anaesthesia.