These speciic ibrin degradation products are generated when fibrinolysin degrades ibrin, as occurs in thromboembolism (Chap. 41, p. 783). heir measurement is frequently incorporated into diagnostic algorithms for VTE in nonpregnant patients (Wells, 2003). Screening with the D-dimer test in pregnancy, however, is problematic for several reasons. As shown in the Appendix (p. 1256), depending on assay sensitivity, D-dimer serum levels rise with gestational age along n= 205Lost to follow-up Untreated during ortreated despite..follow-up Treat noDVT n = 177
Diagnosed with
VTE within 3 mas n= 3 (0.8%)
FIGURE 52-3 Findings from two studies of serial and nonserial compression ultrasound examinations in pregnant and postpartum women. CUS = compression ultrasonography. Df = deep vein thrombosis. VfE = venous thromboembolism. (Data from Chan, 2013;
Le Gal, 201o2.) with substantively elevated plasma fibrinogen concentrations (Murphy, 2015). Levels are also afected by multifetal gestation and cesarean delivery (Morikawa, 2011). D-Dimer concentrations can also be elevated in certain pregnancy complications such as placental abruption, preeclampsia, and sepsis syndrome. Moreover, higher levels have been observed in sickle-cell carriers and in women of Mrican and South Asian racial origin (Grossman, 2016). For all these reasons, their use during pregnancy remains uncertain, but a negative D-dimer test should be considered reassuring (Lockwood, 2012; Marik, 2008).
Optimal management ofVTE during pregnancy has not undergone major clinical study to provide evidence-based practices. here is, however, consensus for treatment with anticoagulation and limited activity. If thrombophilia testing is performed, it is done before anticoagulation. Heparin induces a decline in antithrombin levels, and warfarin lowers protein C and S concentrations. The results of these tests do not change treatment (Connors, 2017).
Anticoagulation is initiated with either unfractionated heparin (UFH) or LMWH. lthough either type is acceptable, most recommend one of the LMWHs (Bates, 2016; Kearon, 2016). For example, the American College of Chest Physicians suggests preferential use of LMWH during pregnancy because of better bioavailability, longer plasma half-life, more predictable dose response, reduced risks of osteoporosis and thrombocytopenia, and less frequent dosing (Bates, 2012). Dosages are shown in Table 52-5.
During pregnancy, heparin therapy is continued, and for postpartum women, anticoagulation is begun simultaneously with warfarin. Recall that pulmonary embolism develops in s many s 60 percent of patients with untreated venous thrombosis, and anticoagulation decreases this risk to less than 5 percent. In nonpregnant patients, the mortality rate with a pulmonary embolism approximates 1 percent (Douketis, 1998; Pollack, 2011).
Over several days, leg pain dissipates. Mter symptoms have abated, graded ambulation is begun. Elastic stockings are itted, and anticoagulation is continued. Recovery to this stage usually takes 7 to 10 days. Graduated compression stockings are continued for 2 years after the diagnosis to reduce the incidence of postthrombotic syndrome (Brandjes, 1997). This syndrome can include chronic leg paresthesias or pain, intractable edema, skin changes, and leg ulcers.