Optimum Platelet Inhibition After Coronary Bypass Surgery

Inclusion Criteria: We intend to invite patients aged 18 to 80 proceeding to primary elective coronary artery bypass surgery, able to give informed consent. Exclusion Criteria: Preoperative exclusion criteria: * patients who are have not stopped aspirin 7 days prior to surgery * patients on concomitant NSAIDS * patients with a previous history platelet disorders, splenectomy or haematological disorders * patients with aspirin induced asthma * patients with any contraindications to aspirin (GI bleed) * patients who are on any medication that may result in a serious drug interaction with aspirin (warfarin) * Women of childbearing potential * Patients of less than 18 years * If informed consent cannot be obtained * If for any reason the consultant surgeon or anaesthetist deems it to be appropriate Operative exclusion criteria: • Concomitant procedures Postoperative exclusion criteria: * patients who receive platelet transfusion * patients who receive NSAIDS * requirement for intra aortic balloon pump support * failure of extubation within 24 hours