Xa, with some direct anti-thrombin activity as well. The disadvantage of danaparoid includes a 10–20% in vitro cross-reactivity with HIT antibodies and long half-life. [Q7:

B, C, E]

IVC filters are intended to prevent pulmonary emboli following filter insertion. Anticoagulation should be continued whenever possible to prevent further thrombosis.25,26 The primary indication for the insertion of an IVC filter is the occurrence of a complication of or contraindication for anticoagulation therapy. Less frequent indications for the insertion of an IVC filter are recurrent thromboembolism despite adequate anticoagulation therapy and chronic recurrent pulmonary embolism with pulmonary hypertension.

Finally, IVC filters have been used for pulmonary embolism prophylaxis in patients with proximal DVT who are at high risk for bleeding and selected trauma patients (pelvic fracture) who are at high risk for VTE and cannot be managed with effective prophylaxis.

[Q8: A, B, D]

Restoring patency by eliminating the thrombus in the deep venous system is the ideal goal of therapy for acute DVT. Many reports have shown that lysis can be achieved and patency restored with thrombolysis, and that long-term sequelae occur less often with successful treatment.27 Systemic thrombolytic therapy for lower-extremity DVT is associated with a 40–60% success rate. While recanalisation is better than standard anticoagulation, the increased risk of bleeding complications has reduced enthusiasm for thrombolysis.

It has been shown that patients with iliofemoral DVT treated with catheter-directed thrombolysis have better functioning and wellbeing than patients treated with anticoagulation alone.28 Currently, it is recommended that lytic agents be delivered via catheterdirected technique into the thrombus. Thrombolytic therapy is recommended for patients with iliofemoral DVT and selected patients with infrainguinal DVT who are severely symptomatic due to multilevel thrombosis. [Q9: C, D]

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