title: Preoperative angiotensin-converting enzyme inhibitor use is not associated with increased postoperative pain and opioid use.
abstract: OBJECTIVE
  Angiotensin-converting enzyme inhibitors (ACEIs) increase potent proinflammatory and pain mediators in local tissues. Consistent with these observations, animal and human studies demonstrate that ACEIs have hyperalgesic and proinflammatory properties. However, there is no information in literature whether or not the use of ACEIs is associated with increased postoperative pain. Specifically, we tested the primary hypothesis that use of ACEIs is independently associated with increased opioid requirements and pain scores during the initial 72 hours after surgery.
  
  
  METHODS
  Data from 9993 patients undergoing colorectal resection, hysterectomy, nephrectomy, or open prostatectomy were obtained from the Cleveland Clinic Perioperative Health Documentation System. A propensity-matching procedure was used to pair ACEI users to similar nonusers. Corresponding estimates and Bonferroni-adjusted 95% confidence intervals for the effect of ACEIs on each outcome were also estimated. The exact matching procedure, based on type of surgery and propensity score, identified 1038 matched pairs. The final analyzed subsample size was 212.
  
  
  CONCLUSIONS
  The adjusted difference in mean 72-hour postoperative using a time-weighted average pain score was estimated at +0.17 [-0.40, +0.74] units on the verbal response scale. This was not statistically significant (P=0.50). Opioid use was estimated by the percent difference in mean 72-hour total postoperative intravenous morphine equivalent dose at -8.1% [-46%, +56%], which was not statistically significant (P=0.72). In conclusion, after controlling for all available factors, we found no significant difference that postoperative pain-as defined by either pain scores or opioid requirements-differed between patients taking ACEIs and patients not taking ACEIs.
authors.affiliation: Departments of *Outcomes Research ‡Quantitative Health Sciences and Outcomes Research §Anesthesiology Institute, Cleveland Clinic ∥Case Western Reserve University, Cleveland, OH †Gulhane Military Medical Academy, Ankara, Turkey ¶School of Public Health, Rochester University, Rochester, NY.
authors.forename: Alparslan
authors.initials: A
authors.lastname: Turan
authors.forename: Abdulkadir
authors.initials: A
authors.lastname: Atim
authors.forename: Jarrod E
authors.initials: JE
authors.lastname: Dalton
authors.forename: Worasak
authors.initials: W
authors.lastname: Keeyapaj
authors.forename: Weihan
authors.initials: W
authors.lastname: Chu
authors.forename: Ethan
authors.initials: E
authors.lastname: Bernstein
authors.forename: Alexander
authors.initials: A
authors.lastname: Fu
authors.forename: Lee
authors.initials: L
authors.lastname: Jae Ho
authors.forename: Leif
authors.initials: L
authors.lastname: Saager
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Sessler
mesh_terms: D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000627:therapeutic use*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D006333:Heart Failure / Q000188:drug therapy; D006801:Humans; D006973:Hypertension / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000627:therapeutic use*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy / Q000209:etiology*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000701:Analgesics, Opioid; D000806:Angiotensin-Converting Enzyme Inhibitors; D009020:Morphine