Propranolol for the prevention of postoperative arrhythmias in general thoracic surgery

Background. Prevention of postoperative arrhythmias in patients undergoing general thoracic surgery is desirable to prevent morbidity. Methods. A randomized, double-blind, placebo controlled trial of propranolo l (10 mg every 6 hours) for 5 days was undertaken in patients undergoing ma jor thoracic operations to determine whether arrhythmias requiring treatmen t could be reduced. Secondary outcomes included overall arrhythmia rate, ad verse events, and length of stay. Arrhythmias were assessed by 72-hour Holt er monitoring. Patients with a history of heart failure, asthma, advanced h eart block, preexisting arrhythmias, sensitivity to propranolol, or use of antiarrhythmic drugs were excluded. Results. Using the intention-to-treat principle there was a 70% relative ri sk reduction from 20% to 6% in the rate of treated arrhythmias with propran olol (p = 0.071, 95% confidence interval 0.6% to 27.2%). Overall arrhythmia s were common but usually benign. Adverse effects were common, although gen erally mild with hypotension and bradycardia being reported more often in t he propranolol group. Length of stay was not different. Conclusions. There was a trend to a reduction in the risk of perioperative arrhythmias with propranolol. Moreover, propranolol was well tolerated show ing a slight increase in minor adverse events. (C) 1999 by The Society of T horacic Surgeons.