Adenosine diphosphate-induced single-platelet count aggregation and bleeding in clopidogrel-treated patients undergoing coronary artery bypass grafting.
OBJECTIVE
To investigate the association between adenosine diphosphate (ADP)-induced platelet aggregation measured by single-platelet count testing and postoperative blood loss in clopidogrel-treated patients with acute coronary syndromes undergoing coronary artery bypass grafting (CABG).


METHODS
Prospective observational study.


METHODS
Clinical study in one cardiac surgery center.


METHODS
Eighty-eight patients treated with clopidogrel (300-600 mg loading dose followed by 75 mg daily) within 7 days before CABG.


METHODS
Platelet function was assessed preoperatively by single-platelet count ADP-induced platelet aggregation. Postoperative blood loss and transfusion requirements were recorded.


RESULTS
There was no significant association between ADP-induced platelet aggregation and blood loss 12 hours postoperatively (estimate -7.51; 95% confidence interval [CI]: -16.9-1.9; p = 0.12). ADP-induced platelet aggregation was associated significantly with the number of platelet concentrates administered within 24 hours after surgery (incidence rate ratio [IRR] 0.95; 95% CI: 0.92-0.98; p<0.01), but not to the number of packed red blood cells (IRR 0.98; 95% CI: 0.95-1.01; p = 0.14).


CONCLUSIONS
Preoperative ADP-induced platelet aggregation measured by single-platelet count testing in clopidogrel-treated patients with acute coronary syndromes undergoing CABG was not associated with postoperative blood loss or packed red blood cells transfused, but was associated significantly with number of platelet concentrates administered during the initial 24 postoperative hours.
Department of Cardiothoracic Surgery and Anesthesiology, Karolinska University Hospital; Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden. Electronic address: magnus.dalen@karolinska.se.
Magnus
M
Dalén
Department of Cardiothoracic Surgery and Anesthesiology, Karolinska University Hospital; Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
Jan
J
van der Linden
Department of Cardiothoracic Surgery and Anesthesiology, Karolinska University Hospital; Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
Manne
M
Holm
Department of Cardiothoracic Surgery and Anesthesiology, Karolinska University Hospital; Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
Gabriella
G
Lindvall
Department of Cardiothoracic Surgery and Anesthesiology, Karolinska University Hospital; Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
Torbjörn
T
Ivert
D054058:Acute Coronary Syndrome / Q000097:blood / Q000601:surgery; D000244:Adenosine Diphosphate / Q000494:pharmacology*; D000368:Aged; D000758:Anesthesia; D001241:Aspirin / Q000627:therapeutic use; D001803:Blood Transfusion; D015505:Chest Tubes; D000077144:Clopidogrel; D016001:Confidence Intervals; D001026:Coronary Artery Bypass; D003422:Critical Care; D004906:Erythrocyte Count; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D010976:Platelet Count; D010979:Platelet Function Tests; D019106:Postoperative Hemorrhage / Q000453:epidemiology*; D011446:Prospective Studies; D012307:Risk Factors; D013988:Ticlopidine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use
D010975:Platelet Aggregation Inhibitors; D000244:Adenosine Diphosphate; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin
clopidogrel; coronary artery bypass; platelet function tests; platelets; postoperative bleeding