title: Bleeding outcomes associated with coronary artery bypass graft surgery and recent clopidogrel exposure.
abstract: BACKGROUND
  Guidelines recommend discontinuing clopidogrel for at least 5 days before elective coronary artery bypass graft surgery (CABG) to limit blood transfusions and for at least 24 hours before urgent CABG to reduce major bleeding complications. Studies have produced conflicting results regarding whether recent exposure to clopidogrel increases bleeding, the need for intraoperative and postoperative blood products, postoperative complications, and hospital length of stay. We evaluated the effect of clopidogrel exposure on major bleeding at our institution within 5 days of CABG.
  
  
  METHODS
  We conducted a retrospective review of patients who underwent CABG at a tertiary academic medical center. The primary outcome was major bleeding, defined as transfusion of 4 units of packed red blood cells (PRBCs) and/or a need for reexploration. Secondary outcomes included non-life-threatening bleeding, defined as transfusion of 2 units but <4 units of PRBCs; postoperative complications; hospital length of stay; readmission within 30 days of the procedure; and hospital mortality. Major bleeding events were analyzed with a logistic regression model that adjusted for covariates of bleeding risk factors.
  
  
  RESULTS
  Of the 715 patients we reviewed, 169 patients received clopidogrel within 5 days before CABG, and 546 patients did not. A significantly higher incidence of major bleeding was observed in the clopidogrel group compared with the group not exposed to clopidogrel (32% versus 17%, P = .002). After adjusting for covariates, patients exposed to clopidogrel had significantly higher odds of major bleeding (odds ratio, 2.1; 95% confidence interval, 1.3-3.4; P = .003). The groups were similar with respect to postoperative complications, except for infection. The clopidogrel-exposed group had a significantly higher rate of leg site infections (3% versus 0.2%, P = .003).
  
  
  CONCLUSIONS
  Clopidogrel exposure within 5 days of CABG is associated with an increased risk of major bleeding.
authors.affiliation: Department of Pharmacy, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA. Danielle.blais@osumc.edu
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Blais
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Zukkoor
authors.forename: Charles
authors.initials: C
authors.lastname: Hayes
authors.forename: Kerry K
authors.initials: KK
authors.lastname: Pickworth
authors.forename: Kyle
authors.initials: K
authors.lastname: Porter
authors.forename: Michael S
authors.initials: MS
authors.lastname: Firstenberg
mesh_terms: D015984:Causality; D000077144:Clopidogrel; D015897:Comorbidity; D001026:Coronary Artery Bypass / Q000401:mortality*; D064420:Drug-Related Side Effects and Adverse Reactions / Q000401:mortality*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009820:Ohio / Q000453:epidemiology; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D019106:Postoperative Hemorrhage / Q000401:mortality*; D015995:Prevalence; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D015996:Survival Rate; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine