A comparison of the incidence and nature of cardiac dysrhythmias occurring during enflurane and isoflurane anaesthesia for dental surgery

The incidence and nature of dysrhythmias with equipotent concentrations of enflurane and isoflurane during dental surgery were compared. Seventy-six Chinese patients between 17-30 years, of ASA Grade I, randomly received either enflurane or isoflurane with N2O and O2 for spontaneous ventilation during third molar extractions. The cardiac rhythm and the blood pressure were continuously monitored during the procedure. The incidence of dysrhythmias with both enflurane and isoflurane was low and the difference not statistically significant. During surgery one patient exhibited unifocal ventricular ectopics with isoflurane. Sinus tachycardia was common with both agents. No life-threatening dysrhythmias were seen with either agent and no clinically significant lowering of blood pressure occurred in association with the exhibited dysrhythmias. In this Chinese population, as in other studies, the incidence of dysrhythmias with both agents was low thus showing no difference between the races.