The association between thromboelastographic parameters and total estimated blood loss in patients undergoing elective cesarean delivery.

BACKGROUND: In this study, we assessed the relationship between coagulation parameters using kaolin-activated thromboelastography (TEG ® ) and total estimated blood loss (EBL) in patients undergoing elective cesarean delivery (CD). METHODS: TEG ® parameters were recorded in 52 patients before and after elective CD. Laboratory markers of coagulation (prothrombin time, activated partial thromboplastin time, fibrinogen) were also assessed in a smaller subset (21 patients). Correlation and linear regression analysis was used to assess the relationship among TEG ® parameters, relevant clinical variables, and total EBL. Secondary analysis included comparisons of TEG ® and coagulation profiles pre-CD versus post-CD. RESULTS: EBL weakly correlated with percentage change in maximum amplitude (r = 0.3; P = 0.04) and post-CD maximum rate of thrombus generation (r = 0.31; P = 0.02). Post-CD values for split point, reaction time, time to maximum rate of thrombin generation, prothrombin time, and activated partial thromboplastin time were significantly increased compared with baseline values (P < 0.05). Post-CD α angle, maximum amplitude, total thrombus generation, fibrinogen, and platelet counts were significantly decreased compared with baseline values (P < 0.05). CONCLUSIONS: There is a weak association between clot strength (as assessed by kaolin-activated TEG ® ) and EBL in patients undergoing elective CD under neuraxial anesthesia, and a modest reduction in the degree of maternal hypercoagulability occurs in the early postpartum period after elective CD.