Thromboelastographic Study to Assess Age-related Coagulation Profile Differences in Parturients Undergoing Elective Cesarean Delivery
Abstract Number: O2 5
Abstract Type: Original Research
Background: Epidemiologic studies indicate that women of advanced maternal age (AMA) are at increased risk of postpartum venous thromboembolism (VTE).(1,2) However, it is uncertain whether these differential risk profiles are explained by differences in the peripartum coagulation profile of AMA women compared to non-AMA women. The aim of this prospective study was to compare the peripartum coagulation profiles of AMA women (age >35 y) vs. non-AMA women (age ≤35 y) undergoing elective cesarean delivery (CD).
Methods: After IRB approval, we enrolled 46 healthy term parturients undergoing scheduled CD with neuraxial anesthesia. AMA and non-AMA women were recruited using block randomization. Kaolin-activated thromboelastography (TEG) and laboratory coagulation parameters (PT, APTT, platelets, fibrinogen) were compared between groups prior to CD and on postoperative days (POD) 1 and 3. Longitudinal analyses of individual TEG and laboratory coagulation indices were performed using a linear mixed-effects regression model (using SAS PROC MIXED) with study group and time as fixed effects; possible interaction of these factors were also examined. Data are presented as mean (SD), median [IQR]; P<0.05 as statistically significant.
Results: TEG and laboratory data prior to surgery and on POD 1 and 3 are presented in the Table. Based on individual models, no significant between-group differences were observed for any TEG or laboratory coagulation parameter at any time point. We found a significant time-effect overall for specific TEG parameters: MA (P<0.001), G (P<0.001), CL30 (P=0.004), and laboratory parameters: PT, APTT, platelets, fibrinogen (P<0.001 respectively). No time x group interaction was observed for any TEG or laboratory coagulation parameter.
Conclusion: Based on the TEG and laboratory coagulation data in this study, healthy AMA women have similar peripartum coagulation profiles as healthy non-AMA women undergoing elective CD. Temporal-related changes in fibrinogen concentration and platelet count may influence maximal clot formation during the early period after elective CD. Future mechanistic and etiologic studies are needed to fully investigate the pathophysiology of postpartum VTE in AMA women.
Refs: (1) Ann Intern Med 2005 2005;143:697-706. (2) Br J Haematol 2012;156:366-73.