Optimum Platelet Inhibition After Coronary Bypass Surgery

Optimum Platelet Inhibition After Coronary Artery Bypass Surgery: A Randomised Trial Comparing Platelet Aggregation Using Low, Medium Dose Aspirin and Clopidogrel

To investigate the effect of different dosages of aspirin on platelet aggregation and to determine the possible mechanisms of aspirin resistance, we intend to compare the effects of low, medium dose aspirin with clopidogrel (an alternative antiplatelet agent) in patients after coronary artery 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