title: Preoperative renin-angiotensin system inhibitors protect renal function in aging patients undergoing cardiac surgery.
abstract: BACKGROUND
  Renal failure (RF) represents a major postoperative complication for elderly patients undergoing cardiac surgery. This observational cohort study examines effects of preoperative use of renin-angiotensin system (RAS) inhibitors on postoperative renal failure in aging patients undergoing cardiac surgery.
  
  
  RESULTS
  We retrospectively analyzed a cohort of 1287 patients who underwent cardiac surgery at this institution (2003-2007). The patients included were ≥65 years old, scheduled for elective cardiac surgery, and without preexisting RF (defined by the criteria of the Society of Thoracic Surgeons as described in Method). Of all patients evaluated, 346 patients met the inclusion criteria and were divided into two groups: using (n = 122) or not using (n = 224) preoperative RAS inhibitors. A comparison of the two groups showed no significant differences in baseline parameters, including creatinine clearance, body mass index, history of diabetes and smoking, preoperative medicines (except that more patients with RAS inhibitors had a history of hypertension or congestive heart failure, fewer RAS inhibitor patients had chronic lung disease), in intraoperative perfusion and aortic cross-clamp time, and in postoperative complications and 30-d mortality. Multivariate logistic regression analysis demonstrated, however, that preoperative RAS inhibitors significantly and independently reduced the incidence of postoperative RF in the patients undergoing cardiac surgery compared with those not taking RAS inhibitors: 1.6% versus 7.6%, yielding an odds ratio of 0.19 (95 % CI 0.04-0.84, P = 0.029).
  
  
  CONCLUSIONS
  Preoperative RAS inhibitors may have significant renoprotective effects for aging patients undergoing elective cardiac surgery.
authors.affiliation: Department of Anesthesiology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Viachaslau
authors.initials: V
authors.lastname: Barodka
authors.forename: Scott
authors.initials: S
authors.lastname: Silvestry
authors.forename: Ning
authors.initials: N
authors.lastname: Zhao
authors.forename: Xiangyin
authors.initials: X
authors.lastname: Jiao
authors.forename: David J
authors.initials: DJ
authors.lastname: Whellan
authors.forename: James
authors.initials: J
authors.lastname: Diehl
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Sun
mesh_terms: D018674:Adrenergic Antagonists / Q000494:pharmacology* / Q000627:therapeutic use; D000368:Aged; D000375:Aging / Q000502:physiology*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D013504:Cardiovascular Surgical Procedures; D005260:Female; D006801:Humans; D015994:Incidence; D007668:Kidney / Q000187:drug effects* / Q000502:physiology; D016015:Logistic Models; D008297:Male; D011183:Postoperative Complications; D011300:Preoperative Care; D051437:Renal Insufficiency / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D012084:Renin-Angiotensin System / Q000187:drug effects*; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D018674:Adrenergic Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors