title: Correlation between point-of-care platelet function testing and bleeding after coronary artery surgery.
abstract: OBJECTIVE
  To investigate whether point-of-care platelet function testing immediately before coronary artery bypass grafting correlates to postoperative blood loss and transfusion requirements.
  
  
  METHODS
  Blood samples from 50 patients on antiplatelet therapy were analysed by Plateletworks(®). Thirty-three of the patients had received clopidogrel, 300-600 mg loading dose followed by 75 mg once daily, within 7 days. Postoperative chest drainage volume was recorded every hour.
  
  
  RESULTS
  Plateletworks(®) ADP-induced platelet aggregation correlated significantly to postoperative chest drainage volume at 5 hours (r = -0.83; p < 0.01) and 12 hours (r = -0.55; p < 0.01), and the tertile of patients with the lowest aggregation had higher postoperative transfusion requirements (p < 0.01) and about three times larger chest drainage volume than remaining patients during the first 5 hours after surgery (p < 0.01). Cessation of clopidogrel correlated to chest drainage volume at 5 hours (r = -0.48; p < 0.01) and 12 hours (r = -0.47; p < 0.01) after surgery.
  
  
  CONCLUSIONS
  The significant correlation between Plateletworks(®) ADP-induced platelet aggregation and blood loss suggests that this test may be useful to predict risk of excessive bleeding and to guide timing of surgery and bleeding treatment in patients undergoing coronary artery bypass grafting.
authors.affiliation: Department of Cardiothoracic Surgery and Anesthesiology, Karolinska University Hospital, Stockholm, Sweden. magnus.dalen@karolinska.se
authors.forename: Magnus
authors.initials: M
authors.lastname: Dalén
authors.forename: Jan
authors.initials: J
authors.lastname: van der Linden
authors.forename: Gabriella
authors.initials: G
authors.lastname: Lindvall
authors.forename: Torbjörn
authors.initials: T
authors.lastname: Ivert
mesh_terms: D000368:Aged; D001241:Aspirin / Q000009:adverse effects; D001803:Blood Transfusion; D000077144:Clopidogrel; D001026:Coronary Artery Bypass / Q000009:adverse effects; D003331:Coronary Vessels / Q000601:surgery; D005260:Female; D006470:Hemorrhage / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation / Q000502:physiology*; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects / Q000627:therapeutic use; D010979:Platelet Function Tests; D019095:Point-of-Care Systems; D011182:Postoperative Care; D019106:Postoperative Hemorrhage / Q000175:diagnosis*; D013988:Ticlopidine / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin