3- Antiplatelet agents:
Aspirin irreversibly acetylates a serine reside of cyclooxygenase 1, which ultimately decreases the synthesis and release of the platelet-activating molecule thromboxane A2 (TxA2). The aspirin effect is, therefore, permanent and lasts for the lifespan of the circulating platelet (7-10 days).36 There was no increased risk among patients taking perioperative ASA undergoing CABG compared with placebo,37 but it may be associated with increased transfusion requirements.38
Oral P2Y12 receptor antagonists, such as clopidogrel (Plavix) , prasugrel (Effient ) and ticagrelor (Brilinta ), can be more problematic given their more potent antiplatelet effect. Like aspirin, the thienopyridine P2Y12 receptor antagonists clopidogrel and prasugrel covalently modify the receptor and the antiplatelet effect lasts for the lifespan of the platelet. Ticagrelor; however, is a non-thienopyridine P2Y12 receptor antagonist and the antiplatelet effect lasts for approximately 4 days. In patients undergoing urgent CABG with prior ticagrelor administration, serial platelet aggregometry revealed a return to normal platelet function within 3-days.39
The intraoperative use of Cytosorb adsorption, previously used in septic patients, was tested on 55 patients who were on ticagrelor or rivaroxaban and required emergency cardiac surgery, mostly CABG. It was effective in reducing bleeding complications as patients had less postop drainage, with majority not requiring transfusion and none required re-exploration (compared to 37.5% in the non-Cytosorb group).40 Further testing to corroborate their findings and determine its effect on other substrates such as albumin and antibiotics will be important.