title: The influence of hypothermia on transfusion requirement in patients who received clopidogrel in proximity to off-pump coronary bypass surgery.
abstract: OBJECTIVE
  Hypothermia adversely affects the coagulation that could be of clinical significance in patients receiving clopidogrel. We evaluated the influence of hypothermia on transfusion requirements in patients undergoing isolated off-pump coronary artery bypass surgery (OPCAB) who continued clopidogrel use within 5 days of surgery.
  
  
  METHODS
  Protocol-based, prospectively entered data of 369 patients were retrospectively reviewed. The time-weighted average of intraoperative temperatures and the temperature upon ICU admission (TWA-temp) was assessed. Patients were divided into normothermia (≥36°C, n=224) and hypothermia (<36°C, n=145) group. The transfusion requirement for perioperative blood loss was assessed and compared.
  
  
  RESULTS
  Patients with hypothermia were older and had lower body surface area (BSA) than patients with normothermia. Age and BSA adjusted transfusion requirement was significantly larger in the hypothermia group [patients requiring transfusion: 64% versus 48%, p=0.003; number of units: 0 (0-2) units versus 2 (0-3) units, p=0.002]. In multivariate analysis of predictors of perioperative multiple transfusion requirements, hypothermia was identified as an independent risk factor along with age, female gender, BSA, chronic kidney disease, and congestive heart failure.
  
  
  CONCLUSIONS
  Hypothermia was associated with increased transfusion requirement in patients undergoing OPCAB who received clopidogrel in proximity to surgery. Considering the high prevalence and the possibility of hypothermia being a modifiable risk factor, aggressive measures should be undertaken to maintain normothermia in those patients.
authors: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea. aneshim@yuhs.ac.
authors: Bo Ra
authors: BR
authors: Lee
authors: Jong Wook
authors: JW
authors: Song
authors: Young Lan
authors: YL
authors: Kwak
authors: Kyoung Jong
authors: KJ
authors: Yoo
authors: Jae Kwang
authors: JK
authors: Shim
mesh_terms: D000368:Aged; D000077144:Clopidogrel; D047549:Coronary Artery Bypass, Off-Pump / Q000379:methods*; D005260:Female; D006801:Humans; D007035:Hypothermia / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D000077144:Clopidogrel; D013988:Ticlopidine
keywords: Clopidogrel; hypothermia; off-pump coronary artery bypass surgery; transfusion