Attenuation of the cardiovascular responses to subcutaneous adrenaline in neurosurgical patients

Abstract

In 30 neurosurgical patients after induction of anaesthesia and random pretreatment with i.v. propranolol 1 mg or metoprolol 1 mg, heart rate and mean arterial pressure were measured at 30-s intervals after subcutaneous infiltration of adrenaline 1:200000. While metoprolol prevented the cardiovascular effects of adrenaline infiltration, propranolol pretreatment was associated with a highly significant increase (P < 0.01) in mean arterial pressure and a significant decrease (P < 0.05) in heart rate. These results confirm the potentially serious interaction of propranolol and adrenaline during anaesthesia, and support the use of metoprolol instead, to obtund the cardiovascular effects of adrenaline infiltration. © 1992 British Journal of Anaesthesia.