Version July 2025
| Name or class of drug | Clinical considerations | Recommended pre-operative strategy for surgery with brief NPO state | Recommended post-operative strategy for surgery with prolonged NPO state |
| Beta blockers | Abrupt withdrawal can result in hypertension, tachycardia, and myocardial ischemia. Perioperative initiation can prevent postoperative myocardial ischemic events in patients with significantly-increased cardiac risk but may increase risk for stroke. Perioperative initiation of beta blockers is recommended in patients with CAD or ischemia on stress testing who are undergoing vascular surgery; and reasonable in patients with at least one cardiac risk factor who are undergoing vascular surgery, or with CAD or >1 cardiac risk factor undergoing intermediate risk surgery. Perioperative initiation of beta blockers is not recommended in patients with baseline heart rate <60 beats per minute, systolic blood pressure <90 mmHg, or when time is not sufficient for titration. | Continue therapy up to and including day of surgery. | Substitute IV propranolol, metoprolol, or labetalol during NPO state. |
| Alpha 2 agonists | Withdrawal can cause extreme hypertension and myocardial ischemia. | Continue therapy up to and including day of surgery. | Substitute transdermal clonidine as needed. |
| Calcium channel blockers | Conflicting evidence on whether there is an increased risk of bleeding. | Continue therapy up to and including day of surgery. | No IV substitution necessary unless poor hemodynamics (hypertension or arrhythmia). |
| ACE inhibitors and angiotensin receptor blockers | Continuation can result in hypotension, though withholding can result in hypertension. | Continue therapy, especially if the indication is heart failure or poorly controlled hypertension, unless there is high risk for hypotension. | Use parenteral enalaprilat as needed in postoperative period. |
| Diuretics | Continuation can result in hypovolemia and hypotension. | For most patients, we continue therapy up to the day of surgery but hold the morning dose. For patients with heart failure whose fluid balance is difficult to manage, we often continue the diuretic without interruption. | Use parenteral forms as needed in postoperative period. |
| Statins | Continuation may elevate risk of myopathy, but provides cardiovascular protection. | Continue statins. | Resume with oral intake. |
| Non-statin lipid-lowering agents | Niacin and fibric acid derivatives may cause rhabdomyolysis. Bile acid sequestrants interfere with absorption of other medications. | Discontinue day before surgery. | Resume with oral intake. |
