Perioperative beta-blocker use in noncardiac surgery questioned

MedWire News: Researchers have questioned the use of beta blockers for the prevention of adverse clinical outcomes in patients undergoing noncardiac surgery.

Their meta-analysis found no evidence for any reduction in mortality or heart failure with beta blocker use, while reductions in the risks for nonfatal myocardial infarction (MI) and myocardial ischemia were offset by more than a doubling of the risk for nonfatal stroke.

Querying the validity of current American College of Cardiology and American Heart Association guidelines stating that the weight of evidence, in aggregate, supports the use of beta blockers during noncardiac surgery in high-risk patients, Franz Messerli (Columbia University, New York, USA) and team critically reviewed 33 relevant randomized, controlled trials involving over 12,000 patients.

In an advance online publication by The Lancet time to coincide with presentation of the findings at the AHA annual scientific sessions in New Orleans, Louisana, they report that beta blockers were not associated with any significant reduction in the risk for all-cause mortality, cardiovascular mortality, or heart failure.

Beta blockers were associated with significant 35% and 64% reductions in the risks for nonfatal MI and myocardial ischemia, giving numbers needed to treat of 63 and 16, respectively. But these reductions were seen at the expense of the two-fold increase in nonfatal strokes, giving a number needed to harm of 293.

Patients who received beta blockers also had an increased risk for bradycardia and hypotension, at numbers needed to harm of 22 and 17, respectively.

“Beta blockers should not be routinely used for perioperative treatment of patients undergoing noncardiac surgery unless patients are already taking them for clinically indicated reasons,” the authors conclude in their article.

Eric Boersma and Don Poldermans, from the Erasmus Medical Center in Rotterdam, The Netherlands, said in an accompanying Comment article that the net clinical outcome of beta blocker treatment should not be based on the sum of its effects found in the study.

But they call for investigators to release data about clinical conditions and perioperative hemodynamic changes that may have resulted in the observed complications.

“These data will be key for updates of treatment guidelines,” they concluded.

Lancet 2008; Advance online publication