How to prevent bleeding events in on- and off-pump coronary artery bypass patients exposed to clopidogrel preoperatively

Abstract

The effect of clopidogrel on bleeding mainly depends on two factors: (1) observed platelet inhibition, which is depending on inherent platelet activity prior to clopidogrel administration and platelet inhibitory response to clopidogrel and (2) newborn platelets ability to restore normal aggregation after clopidogrel discontinuation.The role of aspirin and clopidogrel on bleeding should separately be assessed by drug specific platelet function tests, facilitating individual therapeutic approach for each antiplatelet agent preoperatively. Such an approach could distinguish patients with high residual platelet activity, thus proclivity to ischemic events, or enhanced platelet inhibition, thus proclivity to excessive bleeding. It would be interesting if authors compared preoperative ischemic events incidence between patients groups with respect to preoperative clopidogrel treatment. Timing of discontinuation as well as intensity of preoperatively administered aspirin and clopidogrel should be tailored according to drug specific platelet function tests in order to minimize both ischemic and bleeding events. In group of patients with pronounced platelet inhibition after aspirin and/or clopidogrel administration, early antiplatelet drug discontinuation should be considered. For elective patients, delaying of surgery in cases of pronounced platelet inhibition after antiplatelet drugs administration should be considered if clinically condition allows. For urgent and/or emergent cases with observed preoperative deep platelet inhibition, the desmopressin administration should be considered [5] as well as intraoperative thromboelastography guided hemostatic therapy which significantly reduces incidence of overall transfusion and mediastinal re-exploration due to excessive bleeding [6]. However, such an approach requires further studies in order to provide platelet function test cut-off values that delineate bleeding as well as ischemic events. According to obtained cut-off values, antiplatelet therapy management should be evaluated in context of clinical outcome.