Enflurane reduces ventilation as depth of anesthesia increases. High PaCO 2 levels can be obtained at deeper levels of anesthesia if ventilation is not supported. Enflurane provokes a sigh response reminiscent of that seen with diethyl ether. There is a decrease in blood pressure with induction of anesthesia, followed by a return to near normal with surgical stimulation. Progressive increases in depth of anesthesia produce corresponding increases in hypotension.
Heart rate remains relatively constant without significant bradycardia.
Electrocardiographic monitoring or recordings indicate that cardiac rhythm remains stable. Elevation of the carbon dioxide level in arterial blood does not alter cardiac rhythm. Studies in man indicate a considerable margin of safety in the administration of epinephrine-containing solutions during enflurane anesthesia. Enflurane anesthesia has been used in excision of pheochromocytoma in man without ventricular arrhythmias. The concomitant administration of lidocaine enhances the safety of the use of epinephrine during enflurane anesthesia.