Postpartum haemorrhage (PPH) is the leading cause of pregnancy-related deaths worldwide, responsible for approximately one quarter of maternal deaths.
PPH remains the leading cause of pregnancy-related deaths worldwide. Typically, bleeding is controlled by timely obstetric measures in conjunction with resuscitation and treatment of coagulopathy. Early recognition of abnormal coagulation is crucial and haemostatic support should be considered simultaneously with other strategies as coagulopathies contribute to the progression to massive haemorrhage.
However, there is lack of agreement on important topics in the current guidelines for management of PPH. A clinical definition of PPH is crucial to understand the treatment recommendations. However, reaching a consensus has previously proven difficult. Traditional definitions are based on volume of blood loss, which is difficult to monitor, can be misleading and leads to treatment delay. According to Hofer et al (2022), PPH should be defined as a cumulative blood loss greater than or equal to 1000 ml or any blood loss associated with clinical and/or laboratory signs of shock/tissue hypoperfusion within 24 hours after birth. However, blood loss greater than 500 ml should trigger close patient monitoring and alert obstetric and anaesthesia care providers.
“Early recognition of coagulopathy is crucial for successful patient management. Haemostatic changes during PPH are not well defined and differ from other types of bleeding such as in trauma. For example, prothrombin time and activated partial thromboplastin time (aPTT) in pregnant women were found to remain mostly normal despite large blood loss of up to 5000 ml,” the authors stated.
A multidisciplinary approach to define PPH considering vital signs, clinical symptoms, coagulation and haemodynamic changes is needed.
“Standardised algorithms or massive haemorrhage protocols should be developed to reduce the risk of morbidity and mortality and improve overall clinical outcomes in PPH. If available, point-of-care testing should be used to guide goal-directed haemostatic treatment,” they said.
Tranexamic acid should be administered as soon as abnormal bleeding is recognised. Fibrinogen concentrate rather than fresh frozen plasma should be administered to restore haemostasis where there is elevated risk of fibrinogen deficiency (such as in catastrophic bleeding or in cases of abruption or amniotic fluid embolism) as it is a more concentrated source of fibrinogen. Lastly, organisational considerations are equally as important as clinical interventions in the management of PPH and have the potential to improve patient outcomes.
CLOTTING FACTOR SUPPLEMENTATION
Restoration and maintenance of clot strength can be supported by administering coagulation factors. Fibrinogen is the first factor to fall to critical levels and can be replaced via fresh frozen plasma (FFP), fibrinogen concentrate or cryoprecipitate depending on availability. FFP has a fibrinogen level of approximately 2 g l−1; therefore, infusion of FFP during PPH can further reduce fibrinogen concentration by dilution if the plasma concentration of the patient is above 2 g l−1. If the plasma fibrinogen concentration is lower than 2 g l−1 substitution through cryoprecipitate or fibrinogen concentrate is needed. Advantages of fibrinogen concentrate include easy administration, convenient storage, standardised fibrinogen content, and low risk of complications such as transfusion-transmitted infection and transfusion-related acute lung injury. In comparison, cryoprecipitate contains additional coagulation factors, such as FVIII, VWF and FXIII. However, it requires thawing prior to administration which can delay the treatment.
Recombinant activated factor VII (rFVIIa) was originally developed for the treatment of haemophilic patients with inhibitors and then used successfully for treating haemorrhages in patients with acquired haemophilia. In the last few years, along with the improvement in the knowledge of its mechanisms of action, rFVIIa has also been used with benefit as a ‘universal haemostatic agent’ in many other nonhaemophilic bleeding situations, including congenital FVII deficiencies, quantitative and qualitative platelet disorders, hepatic failure, liver transplantation, major surgery and trauma rFVIIa was approved by the European Medicines Agency (EMA) in May 2022 for treatment of severe PPH unresponsive to treatment with uterotonics, based on a recent study showing a 40% relative risk reduction in women who received a single dose of rFVIIa compared to standard of care.
CONCLUSION
Early recognition and prompt obstetric treatment are essential to avoid development of coagulopathy and severe PPH as well as the associated maternal morbidity. Suggested recommendations include consensus PPH definition for use in clinical practice for prompt recognition of PPH and recommendations for management during bleeding. Standardised algorithms or massive haemorrhage protocols should be developed to reduce the risk of morbidity/mortality and improve overall clinical outcomes. Where available, VET should be used to guide goal-directed haemostatic treatment in PPH. Organisational factors are equally important as clinical interventions in the treatment of PPH and have the potential to improve patient outcomes.
References
Hofer S, Blaha J, Collins PW, et al. Haemostatic support in postpartum haemorrhage: A review of the literature and expert opinion. Eur J Anaesthesiol. 2023;40:29-38. doi: 10.1097/EJA.0000000000001744. Epub 2022 Sep 22. PMID: 36131564; PMCID: PMC9794135.
Kinra P, Kumar H. Recombinant Factor VIIA. Med J Armed Forces India. 2009;65:59-61. doi: 10.1016/S0377-1237(09)80058-0. Epub 2011 Jul 21. PMID: 27408193; PMCID: PMC4921516.
