Should You Omit Beta Blocker on Day of Surgery in a Known Hypertensive Patient?
No—continue the beta blocker on the day of surgery in patients already taking it chronically for hypertension or any other indication. This is a Class I recommendation with strong evidence that abrupt discontinuation causes life-threatening complications including rebound hypertension, severe angina, myocardial infarction, and ventricular arrhythmias 1, 2, 3.
Core Principle: Never Stop Chronic Beta Blockers Perioperatively
Beta blockers must be continued throughout the perioperative period in all patients already receiving them for ACC/AHA Class I indications, which includes hypertension, coronary artery disease, heart failure, and arrhythmias 1, 2.
The FDA drug label for metoprolol explicitly warns: "Do not abruptly discontinue metoprolol therapy in patients with coronary artery disease. Severe exacerbation of angina, myocardial infarction and ventricular arrhythmias have been reported" 3.
The FDA further states: "Chronically administered beta-blocking therapy should not be routinely withdrawn prior to major surgery" 3.
Evidence Supporting Continuation
Patients who continued beta blockers perioperatively had nearly 50% lower risk of combined adverse cardiac events (cardiac events and/or mortality) compared to those who discontinued them, with odds ratio of 1.97 for adverse events when beta blockers were stopped 4.
This protective effect was even more pronounced in higher cardiac risk patients (odds ratio 5.91 for adverse events when stopped) and persisted up to 1 year postoperatively 4.
The American College of Cardiology and American Heart Association emphasize that the POISE trial's findings about harm from beta blockers do not apply to patients already taking beta blockers chronically—POISE only studied starting high-dose beta blockers acutely on the day of surgery in beta blocker-naïve patients 1, 2.
Practical Management Algorithm
On the Day of Surgery:
- Give the patient's usual morning dose of beta blocker with a small sip of water, even if NPO 2.
- Target heart rate of 60-70 bpm while maintaining systolic blood pressure >100 mmHg 2.
If Patient Cannot Take Oral Medications:
- Switch to intravenous beta blocker to maintain therapy and avoid withdrawal 2.
- The FDA label acknowledges that "the impaired ability of the heart to respond to reflex adrenergic stimuli may augment the risks of general anesthesia," but this risk is far outweighed by the dangers of withdrawal 3.
Intraoperative and Postoperative:
- Continue beta blocker therapy throughout the perioperative period with titrated rate control 1.
- Resume oral beta blocker as soon as the patient can tolerate oral intake 2.
Critical Pitfalls to Avoid
Do not confuse this recommendation with starting new beta blockers perioperatively—starting high-dose beta blockers on the day of surgery in beta blocker-naïve patients is Class III: Harm and increases mortality and stroke risk 2.
Do not hold beta blockers even if blood pressure is well-controlled—the indication for continuation is preventing withdrawal syndrome, not blood pressure management 1, 2.
Do not assume the patient can safely miss "just one dose"—rebound phenomena can occur within 24 hours of discontinuation, particularly in patients with underlying coronary disease 3.
Special Considerations
Even in patients being treated only for hypertension without known coronary disease, it is prudent not to discontinue beta blocker therapy abruptly because coronary artery disease is common and may be unrecognized 3.
If severe bradycardia develops intraoperatively (a known risk), reduce or temporarily stop the beta blocker, but plan to restart as soon as hemodynamically appropriate 3.
For patients with relative contraindications (e.g., bronchospastic disease), the chronic beta blocker should still be continued perioperatively, as the withdrawal risk exceeds the risk of continuing therapy 3, 5.