What is the treatment for Pulmonary Embolism (PE) in pregnancy?

From the Guidelines

The treatment of pulmonary embolism (PE) in pregnancy requires low molecular weight heparin (LMWH) as the first-line therapy, with a weight-adjusted dose and consideration of anti-Xa monitoring in high-risk situations, as recommended by the most recent guidelines 1. The use of LMWH is preferred due to its predictable pharmacokinetics, low risk of heparin-induced thrombocytopenia, and lack of placental crossing, making it a safer option for both the mother and the fetus 1. Some key points to consider in the management of PE in pregnancy include:

• LMWH should be administered at a weight-adjusted dose, with consideration of anti-Xa monitoring in women at extremes of body weight or with renal disease 1
• Unfractionated heparin can be used as an alternative, particularly in situations requiring rapid reversal or in severe renal impairment, but it requires aPTT monitoring and may have a higher risk of osteoporosis with long-term use 1
• Warfarin and direct oral anticoagulants (DOACs) are contraindicated during pregnancy due to their teratogenic effects and ability to cross the placenta, though warfarin may be used postpartum 1
• Thrombolytic therapy is reserved only for massive PE with hemodynamic instability
• For delivery planning, LMWH should be discontinued at least 24 hours before planned induction or cesarean section, and can be resumed 12-24 hours after delivery if there are no bleeding complications 1
• Anticoagulant treatment should be administered for at least 6 weeks after delivery and with a minimum overall treatment duration of 3 months, with consideration of LMWH and warfarin as safe options for breastfeeding mothers 1

From the Research

Diagnosis of Pulmonary Embolism (PE) in Pregnancy

• The diagnosis of PE in pregnancy should not rely solely on clinical symptoms, as they can be non-specific and may lead to delayed or missed diagnosis 2, 3, 4.
• Imaging studies, such as ventilation/perfusion scans or CT pulmonary angiography, should be used to diagnose PE in pregnancy, as the fetal radiation exposure is within safe limits 2, 5.
• The pregnancy-adapted YEARS diagnostic algorithm is a useful tool for diagnosing PE in pregnancy, and can help reduce the need for computed tomographic pulmonary angiography 5.

Treatment of Pulmonary Embolism (PE) in Pregnancy

• Low-molecular-weight heparin (LMWH) is the preferred anticoagulant for the treatment of PE in pregnancy, and should be continued for at least 3 months, including 6 weeks postpartum 2, 4, 5, 6.
• The treatment of PE in pregnancy should be individualized, and may require a multidisciplinary approach, including input from obstetricians, emergency physicians, and other specialists 3, 5, 6.
• Thrombolysis or embolectomy may be considered for pregnant women with PE complicated by hemodynamic instability 6.
• Direct oral anticoagulants should be avoided in women who are pregnant or breastfeeding 5, 6.

Management of Anticoagulants at the Time of Delivery

• The management of anticoagulants at the time of delivery should involve a multidisciplinary individualized approach, using shared decision making to take patient and caregiver values and preferences into account 6.
• Neuraxial analgesia can be given in most patients, provided time windows since last LMWH dose are respected 5.
• Induction of labour or planned caesarean section may be required to allow an appropriate transition to unfractionated heparin, and to avoid delivery in women on therapeutic doses of anticoagulation 2.