Introduction:
Angiotensin-converting enzyme (ACE) inhibitors are commonly prescribed antihypertensives. This class of drugs is advantageous for control of blood pressure because of its many other therapeutic effects often of value to patients with hypertension. When ACE inhibitors are taken within 8 to 24 hours of general anesthesia, intraoperative hypotension is more likely. This hypotension can occur following the induction of anesthesia and can occasionally be refractory to standard treatments such as administration of a fluid bolus, ephedrine, or phenylephrine.
In addition, continued preoperative use of ACE inhibitors can be associated with a more profound and persistent hypotension in surgical patients undergoing cardiopulmonary bypass (CPB). This form of ACE inhibitor–associated refractory hypotension is a type of a vasodilatory shock known as vasoplegic syndrome (VS). Vasopressin and methylene blue have emerged as treatment options that are effective in the treatment of VS.
WHAT GUIDELINES SAYS?
The American College of Cardiology and American Heart Association 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery detail specific guidelines for continuing or withholding several classes of antihypertensives in the perioperative period. Noticeably lacking is an unequivocal statement for the perioperative use of ACE inhibitors.
Some recommendations suggest withholding ACE inhibitors the day of surgery and resuming therapy once normal intravascular volume has been restored to prevent renal dysfunction. Withholding of ACE inhibitors preoperatively remains controversial because not all patients develop ACE inhibitor–associated hypotension during anesthesia.
Two 2014 guidelines (2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery; 2014 ESC/ESA Guidelines on non-cardiac surgery: cardiovascular assessment and management) suggested to consider discontinuing ACE inhibitors and ARBs the day before surgery because of the risk of ‘intractable’ hypotension, and increased kidney injury.
After these guidelines were published, a sub-study of the VISION study showed that withholding of ACE inhibitors or ARBs perioperatively reduced the need for vasopressors and decreased the composite outcome (all-cause death, stroke, myocardial injury).
The Canadian Cardiovascular Society perioperative guidelines published in 2017 included an updated review of the literature and provided a strong recommendation to hold ACEIs and ARBs for 24 hours before surgery.
However, a recent meta-analysis including patients from the Vascular Events In Noncardiac Surgery Patients Cohort Evaluation (VISION) cohort study found no association between continuation of these drugs and major adverse cardiac events.
Yoon et al. (2018) systematic review and meta-analysis concluded that no sufficient available evidence to recommend discontinuing ACEIs/ARBs on the day of surgery was found in this literature review and meta-analysis.
Recently published retrospective cohort study Yoon U et al. (2021) in the Journal of Cardiothoracic and Vascular Anesthesia, concludes that continuation of ACE-I/ARB on the day of surgery was not associated with increased risk of intraoperative hypotension upon induction and within 15 minutes of general anesthesia in elective noncardiac surgeries.
CONCLUSION:
Thus ‘consider discontinuing ACE inhibitors and ARBs’ may remain the position of new guidelines. Temporary interruption of ACE inhibitor and ARB therapy is only relevant to arterial hypertension, restarting therapy as soon as possible. In patients with heart failure, ACE inhibitors and ARBs should not be stopped, and adequate monitoring is necessary.
Ref:
- Andrea Thoma, CRNA, MS. Pathophysiology and Management of Angiotensin- Converting Enzyme Inhibitor–Associated Refractory Hypotension During the Perioperative Period. AANA Journal April 2013 Vol. 81, No. 2
- Fleisher LA, Fleischmann KE, Auerbach AD, Barnason SA, Beckman JA, Bozkurt B, et al. 2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery: Executive Summary. Journal of the American College of Cardiology. 2014 Dec;64(22):2373–405.
- 2014 ESC/ESA Guidelines on non-cardiac surgery: cardiovascular assessment and management. European Heart Journal. 2014 Aug 1;35(35):2383–431.
- Foëx P, Sear JW. Implications for perioperative practice of changes in guidelines on the management of hypertension: challenges and opportunities. British Journal of Anaesthesia. 2021 Sep;127(3):335–40.
- Ling, Q., Gu, Y., Chen, J. et al. Consequences of continuing renin angiotensin aldosterone system antagonists in the preoperative period: a systematic review and meta-analysis. BMC Anesthesiol 18, 26 (2018).
- Yoon U, Setren A, Chen A, Nguyen T, Torjman M, Kennedy T. Continuation of Angiotensin-Converting Enzyme Inhibitors on the Day of Surgery Is Not Associated With Increased Risk of Hypotension Upon Induction of General Anesthesia in Elective Noncardiac Surgeries. Journal of Cardiothoracic and Vascular Anesthesia. 2021 Feb;35(2):508–13.
- Duceppe E, Parlow J, MacDonald P, Lyons K, McMullen M, Srinathan S, et al. Canadian Cardiovascular Society Guidelines on Perioperative Cardiac Risk Assessment and Management for Patients Who Undergo Noncardiac Surgery. Canadian Journal of Cardiology. 2017 Jan;33(1):17–32.
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