title: Clinical consequences of withholding versus administering renin-angiotensin-aldosterone system antagonists in the preoperative period.
abstract: BACKGROUND
  Hospitalists involved in perioperative care either stop or continue until the day of surgery renin-angiotensin-aldosterone system antagonists (either angiotensin-converting enzyme inhibitors [ACEI] or angiotensin II receptor subtype 1 antagonists [ARA]) in patients who use these agents chronically. This practice variation reflects uncertainty regarding the risks and benefits of either approach.
  
  
  OBJECTIVE
  The purpose of this study was to assess the clinical consequences of preoperatively continuing versus withholding ACEI/ARAs in patients treated chronically with these agents.
  
  
  METHODS
  We comprehensively searched 7 major electronic databases, considered references from selected reviews, hand-searched journals, and communicated with experts. We included randomized trials and observational studies.
  
  
  METHODS
  We evaluated the relative risk (RR) of hypotension requiring vasopressors and of myocardial infarction in patients who did or did not receive an immediate preoperative dose of ACEI or ARA.
  
  
  RESULTS
  Random-effects meta-analysis from 5 studies totaling 434 patients suggested that patients receiving an immediate preoperative ACEI/ARA dose were more likely (RR 1.50, 95% CI 1.15-1.96) to develop hypotension requiring vasopressors at or shortly after induction of anesthesia. Sufficient data were not available to assess other outcomes.
  
  
  CONCLUSIONS
  Preoperative administration of ACEI/ARAs increases intraoperative hypotension. The long-term clinical consequences of continuing versus withholding preoperative ACEI/ARAs are unknown. This uncertainty stems in part from the absence to date of randomized trials designed specifically to examine patient-important consequences of this decision.
authors.affiliation: Knowledge and Encounter Research Unit, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA. Rosenman.david@mayo.edu
authors.forename: David J
authors.initials: DJ
authors.lastname: Rosenman
authors.forename: Furman S
authors.initials: FS
authors.lastname: McDonald
authors.forename: Jon O
authors.initials: JO
authors.lastname: Ebbert
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Erwin
authors.forename: Matthew
authors.initials: M
authors.lastname: LaBella
authors.forename: Victor M
authors.initials: VM
authors.lastname: Montori
mesh_terms: D047228:Angiotensin II Type 1 Receptor Blockers / Q000008:administration & dosage* / Q000009:adverse effects; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D007022:Hypotension / Q000188:drug therapy / Q000503:physiopathology; D009203:Myocardial Infarction / Q000188:drug therapy / Q000503:physiopathology; D011300:Preoperative Care / Q000379:methods*; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment; D016896:Treatment Outcome
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors