Use of abciximab-modified thrombelastography in patients undergoing cardiac surgery

Thrombelastography (TEG) is a reliable coagulation monitoring system that c an guide blood product transfusion in cardiac surgery. The maximum amplitud e (MA) of TEG measures clot strength, which is dependent on both fibrinogen level and platelet function. Inhibition of platelet function with abcixima b-fab is suggested to permit quantitative assessment of the contribution of fibrinogen to clot strength. We hypothesized that abciximab-modified TEG p ermits prediction of plasma fibrinogen levels and that the difference of st andard MA and abciximab-modified MA (Delta MA) is a correlate for platelet function. We correlated abciximab-modified MA with plasma fibrinogen levels and Delta MA with platelet count in patients undergoing coronary revascula rization. Correlation between plasma fibrinogen levels and abciximab-modifi ed MA was significant (adjusted r(2): 0.8; P < 0.0001). Correlation of Delt a MA with platelet count was not significant when calculated in millimeters (adjusted r(2): 0.04; P = 0.73). However, when Delta MA was calculated in dynes per square centimeter (Delta GMA), it correlated significantly with p latelet count (adjusted r(2): 0.51; P < 0.0001). We conclude that abciximab -modified TEG may therefore help to discriminate between hypofibrinogenemia and platelet dysfunction as a cause of decreased MA. Implications: We exam ined the use of abciximab-modified thrombelastography in patients undergoin g cardiac surgery. Modification of thrombelastography with abciximab-fab al lows prediction of fibrinogen levels, despite coagulation altered by cardia c surgery. The difference of standard maximum amplitude and abciximab-modif ied maximum amplitude correlates with platelet function when expressed in d ynes per square centimeter.