George J. Despotis, MD

Research Interests

Initial studies were designed to validate point-of-care coagulation and platelet function instruments with respect to accuracy, reproducibility and ability to identify patients at risk for bleeding. Subsequent studies have examined the clinical utility of these methods. Point-of-care (POC) diagnostic systems, when incorporated into treatment algorithms, were shown to optimize the perioperative management (i.e., using either pharmacologic or transfusion-based therapies) of bleeding patients. Initial use of whole blood PT, aPTT and platelet count have been enhanced by incorporation of new, point-of-care platelet function tests.

After identifying factors that were associated with excessive bleeding and transfusion, several studies were performed to validate point-of-care methods with respect to monitoring of heparin anticoagulation/neutralization. Optimal management of anticoagulation/reversal (i.e., heparin and protamine dosing) led to reduced transfusion requirements and blood loss after cardiac surgery. Maintenance of patient-specific heparin concentrations during extracorporeal circulation resulted in preservation of coagulation factors (i.e., factors V, VIII, fibrinogen, AT III), platelets (i.e., using bleeding time) secondary to better suppression of thrombin (fibrinopeptide A) and fibrinolytic (D-dimers) activity. Point-of-care methods, as well as antithrombotic agents, also were used to optimize anticoagulation for ventricular assist devices in two recent reports. Several projects involving platelet donor safety, plasma apheresis and stem cell collection procedures have been pursued in the transfusion medicine environment. Other projects have focused on the use of novel (recombinant antithrombin III) agents to preserve hemostasis during extracorporeal circulation to minimize transfusion-related and thrombotic sequalae