Acute obstetric coagulopathy during postpartum hemorrhage is caused by hyperfibrinolysis and dysfibrinogenemia: an observational cohort study

• Published in: Journal of thrombosis and haemostasis Vol. 21; no. 4; pp. 862 - 879
• Main Authors: de Lloyd, Lucy, Jenkins, Peter V., Bell, Sarah F., Mutch, Nicola J., Martins Pereira, Julia Freyer, Badenes, Pilar M., James, Donna, Ridgeway, Anouk, Cohen, Leon, Roberts, Thomas, Field, Victoria, Collis, Rachel E., Collins, Peter W.
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01.04.2023
• Subjects: Afibrinogenemia - complications; Afibrinogenemia - diagnosis; Antifibrinolytic Agents; Blood Coagulation Disorders; coagulopathy; Cohort Studies; dysfibrinogenemia; Embolism, Amniotic Fluid; Female; fibrinogen; Fibrinogen - metabolism; Fibrinolysin - metabolism; fibrinolysis; Hemostatics; Humans; Infant, Newborn; Placenta; postpartum hemorrhage; Postpartum Hemorrhage - diagnosis; Postpartum Hemorrhage - etiology; Pregnancy; fibrinolysis; postpartum hemorrhage; dysfibrinogenemia; coagulopathy; fibrinogen
• DOI: 10.1016/j.jtha.2022.11.036
• ISSN: 1538-7836

Postpartum hemorrhage (PPH) may be exacerbated by hemostatic impairment. Information about PPH-associated coagulopathy is limited, often resulting in treatment strategies based on data derived from trauma studies. To investigate hemostatic changes associated with PPH. From a population of 11 279 maternities, 518 (4.6%) women were recruited with PPH ≥ 1000 mL or placental abruption, amniotic fluid embolism, or concealed bleeding. Routine coagulation and viscoelastometric results were collated. Stored plasma samples were used to investigate women with bleeds > 2000 mL or those at increased risk of coagulopathy defined as placenta abruption, amniotic fluid embolism, or need for blood components. Procoagulant factors were assayed and global hemostasis was assessed using thrombin generation. Fibrinolysis was investigated with D-dimer and plasmin/antiplasmin complexes. Dysfibrinogenemia was assessed using the Clauss/antigen ratio. At 1000 mL blood loss, Clauss fibrinogen was ≤2 g/L in 2.4% of women and 6/27 (22.2%) cases of abruption. Women with very large bleeds (>3000 mL) had evidence of a dilutional coagulopathy, although hemostatic impairment was uncommon. A subgroup of 12 women (1.06/1000 maternities) had a distinct coagulopathy characterized by massive fibrinolysis (plasmin/antiplasmin > 40 000 ng/mL), increased D-dimer, hypofibrinogenemia, dysfibrinogenemia, reduced factor V and factor VIII, and increased activated protein C, termed acute obstetric coagulopathy. It was associated with fetal or neonatal death in 50% of cases and increased maternal morbidity. Clinically significant hemostatic impairment is uncommon during PPH, but a subgroup of women have a distinct and severe coagulopathy characterized by hyperfibrinolysis, low fibrinogen, and dysfibrinogenemia associated with poor fetal outcomes. •Hemostatic failure may exacerbate postpartum hemorrhage, but the coagulopathy is not well defined.•This study described hemostasis in a cohort of women with postpartum hemorrhage (PPH) to inform evidence-based treatment.•Hemostatic impairment was uncommon during PPH, but dilution of coagulation factors occurred with bleeds >3000 mL.•Severe coagulopathy due to hyperfibrinolysis and hypodysfibrinogenemia occurred in 1/1000 cases.