Should Angiotensin Receptor Blockers (ARBs) or Calcium Channel Blockers (CCBs) be stopped prior to surgery?

Management of ARBs and CCBs Prior to Surgery

In patients with hypertension undergoing major surgery, discontinuation of ACE inhibitors or ARBs perioperatively may be considered, while CCBs can generally be continued until surgery. 1

ARB Management Before Surgery

Recommendations for ARBs:

• Discontinuation of ARBs 24 hours before major surgery may be considered to reduce the risk of intraoperative hypotension 1, 2
• If ARBs are held before surgery, they should be restarted as soon as clinically feasible postoperatively when volume status is stable 1, 2
• For patients with left ventricular systolic dysfunction, continuing ARBs perioperatively under close monitoring may be reasonable 1, 3

Rationale for ARB Management:

• Perioperative use of ARBs carries a risk of severe hypotension under anesthesia, particularly following induction and with concomitant β-blocker use 1, 3
• Recent evidence from a large cohort study demonstrates that patients who stopped their ARBs 24 hours before noncardiac surgery were less likely to suffer the primary composite outcome (all-cause death, stroke, or myocardial injury) and intraoperative hypotension than those continuing these medications until surgery 1
• Meta-analyses have confirmed that perioperative continuation of ARBs is associated with an increased incidence of intraoperative hypotension, although no significant difference in mortality or major adverse cardiac events has been demonstrated 4

CCB Management Before Surgery

Recommendations for CCBs:

• Calcium channel blockers can generally be continued during non-cardiac surgery 1
• Heart rate-reducing calcium channel blockers, particularly diltiazem, may be considered before non-cardiac surgery in patients who have contraindications to β-blockers 1
• Calcium channel blockers are recommended to be continued during non-cardiac surgery in patients with Prinzmetal angina pectoris 1

Rationale for CCB Management:

• Unlike ARBs, CCBs do not typically cause significant intraoperative hypotension that would warrant discontinuation 1
• Calcium channel blockers have been shown to significantly reduce ischemia and supraventricular tachycardia in the perioperative period 1
• There is no specific recommendation to discontinue CCBs before surgery in major guidelines 1

Special Considerations

High-Risk Scenarios:

• For patients with planned elective major surgery and SBP ≥180 mm Hg or DBP ≥110 mm Hg, deferring surgery may be considered 1
• Patients with intraoperative hypertension should be managed with intravenous medications until oral medications can be resumed 1
• For patients with left ventricular systolic dysfunction, continuing ARBs perioperatively under close monitoring may be beneficial 1, 3

Medication Restart Protocol:

• ARBs should be restarted postoperatively once the patient is hemodynamically stable 1, 2
• Ensure volume status is adequate before restarting ARBs to prevent postoperative hypotension 2, 3
• Monitor blood pressure closely after restarting ARBs or CCBs 1

Common Pitfalls and Caveats

• Abrupt discontinuation of certain antihypertensives (particularly beta-blockers or clonidine) is potentially harmful and should be avoided 1
• Beta-blockers should not be started on the day of surgery in beta-blocker-naïve patients 1
• Continuing ARBs may increase the need for vasopressor support during surgery 2, 4
• Clear communication about which medications to take or withhold on the morning of surgery is essential to avoid confusion 2
• Ensure appropriate monitoring for patients who continue ARBs during surgery due to increased risk of hypotension 1, 4

By following these evidence-based recommendations, clinicians can optimize perioperative management of ARBs and CCBs to reduce the risk of adverse events while maintaining appropriate blood pressure control.