Written by Peter Liu
Spoon Feed
The POISE trial showed that initiating metoprolol therapy shortly before noncardiac surgery results in increased mortality, stroke, bradycardia, and hypotension.
Avoid beta-blocker initiation on the day of surgery
Perioperative medication management is a complex subject, with many conflicting randomized controlled trials (RCTs) and observational trials, indicating the nuances of medication continuation.
The POISE trial, an RCT, studied whether perioperative extended-release metoprolol succinate reduced major cardiovascular events and surgical outcomes in 8,351 beta-blocker naive patients with cardiovascular risk factors undergoing non-cardiac surgery. In the treatment arm, patients received metoprolol succinate 100mg 2-4 hours before surgery, and continued this therapy as soon as 6 hours post-operatively. While this intervention reduced non-fatal myocardial infarction (HR 0.70; 95%CI 0.57–0.86; p=0.0008), it also increased total mortality (HR 1.33; p=0.031), stroke risk (HR 2.17; p=0.005), hypotension (HR 1.55; p<0.001), and bradycardia (HR 2.74; p<0.001), indicating significant safety concerns with this protocol. Subsequent meta-analyses of RCTs studying beta-blocker therapy initiation within a day before noncardiac surgery have shown these findings to be reproducible.
Due to the clear safety issues established in POISE, it is rare for clinicians to advocate for the initiation of beta-blocker therapy close to a non-cardiac procedure with more than minimal risk. The AHA specifically advises against beta-blocker initiation on the day of a noncardiac surgery. However, POISE offers no clear insight into continuation of long-term beta-blocker therapy or slow titration of beta-blocker therapy far removed from a surgery. Experience has generally shown these practices to be lower risk.
How does this change my practice?
Due to trials like POISE, I have followed AHA guidelines on avoiding initiation of beta blockers in perioperative beta-blocker naive patients. When beta-blocker therapy is warranted, I will generally favor a smaller dose of short-acting medication, titrated as far in advance of the surgery as possible.
Source
Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial. Lancet. 2008 May 31;371(9627):1839-47. doi: 10.1016/S0140-6736(08)60601-7. Epub 2008 May 12. PMID: 18479744
