Perioperative Management of Benazepril
Benazepril should be discontinued 24 hours before surgery to reduce the risk of intraoperative hypotension while resuming it postoperatively once volume status is stable. 1
Rationale for Discontinuation
Angiotensin-converting enzyme (ACE) inhibitors like benazepril carry significant risks when continued perioperatively:
- The ACC/AHA guidelines specifically recommend that discontinuation of ACE inhibitors perioperatively may be considered in patients undergoing major surgery (Class IIb, Level B-NR evidence) 2
- Patients who continue ACE inhibitors during surgery experience:
- More frequent episodes of hypotension
- Longer duration of hypotensive episodes
- Increased need for vasoactive drugs 3
- The FDA label for benazepril specifically warns that "in patients undergoing major surgery or during anesthesia with agents that produce hypotension, benazepril may block angiotensin II formation secondary to compensatory renin release" 4
Timing of Discontinuation
- Stop benazepril 24 hours before surgery 1
- This timeframe allows sufficient clearance to minimize the risk of intraoperative hypotension while not being so long as to cause rebound hypertension
Special Considerations
- For patients with left ventricular systolic dysfunction who are in stable clinical condition, continuing ACE inhibitors may be reasonable under close monitoring 1
- If surgery is urgent and benazepril cannot be discontinued, be prepared to:
- Correct hypotension with volume expansion 4
- Have vasopressors readily available
- Monitor blood pressure closely during induction of anesthesia
Postoperative Management
- Resume benazepril as soon as the patient is hemodynamically stable postoperatively 1
- Ensure adequate volume status before restarting
- Monitor blood pressure and renal function when restarting therapy
Comparison with Other Antihypertensive Medications
Unlike ACE inhibitors, some other antihypertensive medications require different perioperative management:
- Beta-blockers should NOT be discontinued abruptly before surgery due to risk of rebound hypertension (Class III: Harm, Level B-NR) 2
- Clonidine should also be continued perioperatively to avoid withdrawal syndrome 2
- For patients on multiple antihypertensive medications, it is reasonable to continue other antihypertensive medications until the day of surgery 2
Potential Pitfalls
- Failing to discontinue benazepril before surgery may lead to severe hypotension that is resistant to vasopressors
- Discontinuing benazepril for too long before surgery (>48 hours) may lead to uncontrolled hypertension
- Not resuming benazepril postoperatively may worsen blood pressure control and increase cardiovascular risk
- Restarting benazepril too early in a volume-depleted patient may cause acute kidney injury
By following these guidelines, you can minimize perioperative cardiovascular risk while avoiding the complications associated with intraoperative hypotension in patients taking benazepril.