Should calcium channel blockers and beta blockers be continued on the day of surgery?

Perioperative Management of Beta Blockers and Calcium Channel Blockers

Beta blockers should be continued through the day of surgery in patients already taking them, while calcium channel blockers should also be continued perioperatively. Abrupt discontinuation of beta blockers is harmful and can precipitate severe cardiovascular events, while calcium channel blockers pose minimal risk when continued 1.

Beta Blocker Management

Continue Existing Therapy

• Patients on chronic beta blocker therapy must continue their medication through the day of surgery 1
• Abrupt withdrawal can cause severe exacerbation of angina, myocardial infarction, and ventricular arrhythmias in patients with coronary artery disease 2
• Early studies suggesting benefit from beta blockers may have actually demonstrated harm from withdrawal in patients on long-term therapy 1
• Clinical judgment should be used to titrate doses perioperatively based on hemodynamics, but the medication should be continued through hospital stay and at discharge unless clear contraindications arise 1

Do Not Initiate on Day of Surgery

• Starting beta blockers on the day of surgery is harmful and increases postoperative mortality 1
• The POISE trial demonstrated that high-dose beta blockers initiated on the day of surgery increased stroke risk and all-cause mortality despite reducing cardiac events 1
• If a new indication for beta blockade exists, initiate at least 7 days before surgery (optimally >31 days) to permit dose titration and assessment of tolerability 1
• Patients who initiated beta blockers <7 days before surgery had higher mortality risk compared to those who started >31 days earlier 1

Key Pitfall to Avoid

The critical error is confusing continuation of existing therapy (which is beneficial and prevents withdrawal complications) with initiation of new therapy on the day of surgery (which is harmful). The FDA label explicitly warns that chronically administered beta-blocking therapy should not be routinely withdrawn prior to major surgery 2.

Calcium Channel Blocker Management

Continue Perioperatively

• Calcium channel blockers should be continued during non-cardiac surgery 1, 3
• Unlike ACE inhibitors and ARBs, calcium channel blockers do not typically cause significant intraoperative hypotension that would warrant discontinuation 3
• They have been shown to reduce ischemia and supraventricular tachycardia in the perioperative period 3

Specific Indications for Continuation

• Mandatory continuation in patients with Prinzmetal (vasospastic) angina to prevent coronary spasm 1
• Heart rate-reducing calcium channel blockers (particularly diltiazem) may be considered in patients with contraindications to beta blockers 1, 3
• Continuation is safe in ambulatory surgery patients and simplifies preoperative instructions 4

Important Caveat

Short-acting dihydropyridines (particularly nifedipine capsules) should be avoided perioperatively, as one study showed dihydropyridine use was independently associated with increased perioperative mortality in aortic aneurysm surgery 1. However, this does not apply to long-acting or extended-release formulations of calcium channel blockers.

Practical Algorithm

For patients on chronic beta blockers:

1. Continue medication through day of surgery at usual dose
2. Monitor hemodynamics perioperatively and titrate as needed
3. Ensure continuation at discharge unless contraindications develop
4. Never abruptly discontinue

For patients on calcium channel blockers:

1. Continue all calcium channel blockers through day of surgery
2. Avoid short-acting nifedipine capsules
3. No dose adjustment typically needed
4. Resume immediately postoperatively

For beta blocker-naïve patients:

1. Do NOT initiate on day of surgery
2. If new indication exists, start ≥7 days before surgery with dose titration
3. Surgery alone is not an indication for beta blockade 1