Perioperative beta-blockers for major noncardiac surgery: Primum Non Nocere.

Recent studies have called into question the benefit of perioperative beta blockade, especially in patients at low to moderate risk of cardiac events. Once considered standard of care, the role of beta-blocker therapy now lies mired in conflicting data that are difficult to apply to the at-risk patient. We provide an overview of the evolution of perioperative beta blockade, beginning with the physiology of the adrenergic system, with emphasis on the biologic rationale for the perioperative implementation of beta-blockers. Although initial studies were small in size and statistically limited, early data showed cardiac benefit with the use of perioperative beta-blockers. However, larger, more recent studies now suggest a lack of benefit and potential harm from this practice. This paradigm holds true especially in those at low-to-moderate cardiovascular risk profiles. Potential explanations for these paradoxical results are discussed, stressing the key differences between earlier and current studies that may explain these divergent outcomes. We conclude by commenting on performance measures as they relate to perioperative beta-blockers and make recommendations for the continued safe implementation of this practice.