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A Postoperative Evaluation Guideline for Computer-Assisted Reconstruction of the Mandible
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Prospective Randomized Evaluation of Preoperative Angiotensin-Converting Enzyme Inhibition (PREOP-ACEI).

Jason F Shiffermiller1, Benjamin J Monson2, Chad W Vokoun3

  • 1Section of Hospital Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA. jshiffermiller@unmc.edu.

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|September 28, 2018
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Summary

Discontinuing angiotensin-converting enzyme inhibitors (ACEI) before noncardiac surgery reduces intraoperative hypotension. This ACEI interruption also decreased postoperative hypotension but increased postoperative hypertension.

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Area of Science:

  • Anesthesiology
  • Cardiovascular Medicine
  • Pharmacology

Background:

  • Intraoperative hypotension increases risks of end-organ damage and mortality.
  • Preoperative interruption of angiotensin-converting enzyme inhibitor (ACEI) therapy is known to reduce intraoperative hypotension in cardiac and vascular surgeries.

Purpose of the Study:

  • To compare two protocols for preoperative ACEI management.
  • To assess the risk of intraoperative hypotension in patients undergoing noncardiac, nonvascular surgeries.

Main Methods:

  • A prospective, randomized study was conducted at an academic medical center.
  • Patients on ACEI for at least six weeks preoperatively were randomized to either omit or continue their final preoperative dose.
  • The primary outcome was intraoperative hypotension (systolic blood pressure < 80 mm Hg).

Main Results:

  • Intraoperative hypotension occurred less frequently in the ACEI omission group (55%) compared to the continuation group (69%).
  • Postoperative hypotensive events were also less frequent in the omission group.
  • However, postoperative hypertensive events were more frequent in the omission group.

Conclusions:

  • Transient preoperative interruption of ACEI therapy is associated with a reduced risk of intraoperative hypotension.
  • This strategy may be beneficial for patients undergoing noncardiac, nonvascular surgeries.
  • Clinicians should monitor for postoperative hypertension following ACEI omission.