Evidence Base for the Management of Venous Thromboembolism in Pregnancy

Abstract

Venous thromboembolism (VTE), comprising deep vein thrombosis (DVT) and pulmonary embolism (PE), is a leading cause of maternal mortality during pregnancy. DVT and PE are commonly suspected due to many mimicking signs and symptoms that are normal in pregnancy. However, validated diagnostic approaches are lacking, and a fear of teratogenic/oncogenic exposure from imaging procedures affects the acceptability of diagnostic approaches used for VTE during pregnancy. DVT and PE treatment in pregnancy is also challenging due to this lack of validated diagnostic approaches, changes in maternal physiology, and the need for intact hemostasis at the time of delivery/epidural analgesia. Prevention requires an optimal balancing of absolute increased bleeding risk from pharmacologic thromboprophylaxis and the absolute benefit of reduced DVT and PE, which, while serious, are relatively uncommon.

Venous thromboembolism in obese pregnant women: approach to diagnosis and management

“…Whereas this may render the CT-PA a better modality form the fetal perspective, it should be noted that the degree of fetal radiation for both CT-PA and the perfusion portion of the V/Q scan are well below the safety thresholds, lack teratogenic associations, and reflect extremely low absolute risks [33]. Conversely, CT-PA delivers 10 mGy of radiation to the maternal breast in contrast to the perfusion part of a V/Q scan which delivers 0.28 mGy; a dose 40 times higher at a sensitive time of rapid breast tissue proliferation, potentially increasing the lifetime risk of breast cancer [27,31].…”

“…Additional relevant elements, such as immobilization, unequal calf-size differing by > 3 cm (measured 10 cm below the tibial tuberosity), or unilateral swelling affecting the entire extremity warrant in-depth assessment [26]. Similarly, less typical presentation consisting of abdominal discomfort, or reports of pain solely in the flank, buttocks, or groin are suspicious in women with an increased risk of VTE and clarification of their etiology should be pursued, as they may be indicative on an iliac vein thrombosis, the risk of which is increased in pregnancy [27].…”

“…In individuals presenting with respiratory symptoms suggestive of a PE, investigation for a DVT is still warranted [16,27,31]. Should a DVT be identified, weight-based therapeutic anticoagulation is required as for a PE, thus further imaging for a PE may be unnecessary, avoiding its inherent radiation exposure [27,31].…”

“…Should a DVT be identified, weight-based therapeutic anticoagulation is required as for a PE, thus further imaging for a PE may be unnecessary, avoiding its inherent radiation exposure [27,31]. Should DVT imaging be negative or unavailable, a ventilation/perfusion (V/Q) scan or computer tomographic pulmonary angiography (CT-PA) is indicated for the diagnosis of PE [16,31].…”

“…Compression ultrasound (CUS) of the venous system is the principal imaging modality for investigation of DVT during pregnancy, as it is non-invasive and allows for avoidance of radiation exposure [27,29]. Targeted examination extending from the iliac vein to the popliteal vein, incorporating Doppler interrogation of iliac vein flow (normally non-compressible) is crucial in view of the risk of iliac vein DVT in pregnancy [16,22,24,30].…”