Thromboelastography (TEG®) and Platelet Function in Patients on Anti-platelet Agents

Pilot Study for the Prediction of Post-operative Thrombotic and Bleeding Complications in Non-cardiac Surgery Using Thromboelastography (TEG®) and Platelet Mapping Assay (PMA™) in Patients on Anti-platelet Agents

Can a post-operative analysis using a simple blood test (Thromboelastography(TEG®)) and Platelet Mapping Assay (PMA™) be able to detect the occurence of clotting or bleeding complications in patients on blood thinning (anti-platelet) agents?

Two hundred patients coming for surgery who are taking anti-platelet medications will be enrolled in this study as a pilot, to determine the feasibility for a larger study. A simple blood test for clotting function will be done after surgery. Patients will be assessed daily during their hospital stay to determine if they have any clotting or bleeding complications. For analysis, groups will be divided into normal and increased or decreased ability to make a blood clot based on the TEG® and PMA™ test done. Complications will be recorded for each group and analyzed to determine if there is any difference between groups.

Inclusion Criteria:

• patients on aspirin and/or clopidogrel for at least 10 days, having non-ambulatory, non-cardiac, elective surgery

Exclusion Criteria:

• anemia (Hb < 100) or thrombocytopenia (platelet count < 80), having any known clotting abnormalities
• family history of clotting abnormalities
• concurrently on NSAIDs, warfarin therapy or other treatments affecting platelet function
• renal impairment (Cr > 110 mg for females or Cr > 125 mg) or INR > 1.2