Beyond uterine atony: characterizing postpartum hemorrhage coagulopathy

Establishment of Risk Nomogram Model of Postpartum Hemorrhage After Second Cesarean Section

Objective

To establish and evaluate a nomogram model for predicting the risk of postpartum hemorrhage in second cesarean section.

Methods

A total of 440 parturients who underwent the second cesarean section surgery and were registered in our hospital from August 2019 to July 2021 were selected as the study subjects. They were randomly divided into 220 modeling group and 220 validation group based on simple randomization. The two groups were divided into postpartum hemorrhage group and postpartum non bleeding group according to whether postpartum hemorrhage occurred.

Results

In the modeling group, the incidence of postpartum hemorrhage in the second cesarean section was 15.00%; the Logistic regression model showed that placenta previa, operation time, prenatal anemia, placenta accreta, uterine inertia were the independent risk factors of postpartum hemorrhage in the second cesarean section (P < 0.05). ROC results showed that AUC of predicting the risk of postpartum hemorrhage in the second cesarean section was 0.824. The slope of calibration curve is close to 1, Hosmer-Lemeshow goodness of fit test showed x2= 7.585, P = 0.250. The external verification results show that the AUC is 0.840, and the predicted probability of the calibration curve is close to the actual probability.

Conclusion

Based on the five risk factors of postpartum hemorrhage in the second cesarean section, including placenta previa, operation time, prenatal anemia, placenta accreta and uterine inertia, the nomogram model for predicting the risk of postpartum hemorrhage in the second cesarean section has good accuracy and differentiation.

CT-001, a novel fast-clearing factor VIIa, enhanced the hemostatic activity in postpartum samples

ABSTRACT

The hemostatic system is upregulated to protect pregnant mothers from hemorrhage during childbirth. Studies of the details just before and after delivery, however, are lacking. Recombinant factor VIIa (rFVIIa) has recently been granted approval by the European Medicines Agency for the treatment of postpartum hemorrhage (PPH). A next-generation molecule, CT-001, is being developed as a potentially safer and more efficacious rFVIIa-based therapy. We sought to evaluate the peripartum hemostatic status of pregnant women and assess the ex vivo hemostatic activity of rFVIIa and CT-001 in peripartum blood samples. Pregnant women from 2 study sites were enrolled in this prospective observational study. Baseline blood samples were collected up to 3 days before delivery. Postdelivery samples were collected 45 (±15) minutes after delivery. Between the 2 time points, soluble fibrin monomer and D-dimer increased whereas tissue factor, FVIII, FV, and fibrinogen decreased. Interestingly, the postdelivery lag time and time to peak in the thrombin generation assay were shortened, and the peak thrombin generation capacity was maintained despite the reduced levels of coagulation proteins after delivery. Furthermore, both rFVIIa and CT-001 were effective in enhancing clotting activity of postdelivery samples in activated partial thromboplastin time, prothrombin time, thrombin generation, and viscoelastic hemostatic assays, with CT-001 demonstrating greater activity. In conclusion, despite apparent ongoing consumption of coagulation factors at the time of delivery, thrombin output was maintained. Both rFVIIa and CT-001 enhanced the upregulated hemostatic activity in postdelivery samples, and consistent with previous studies comparing CT-001 and rFVIIa in vitro and in in vivo, CT-001 demonstrated greater activity than rFVIIa.