The national institute for clinical excellence (NICE) has clear guidelines on anticoagulation following a venous thromboembolic event.

NICE states that all patients with a confirmed proximal DVT or pulmonary embolus (PE) should be offered a choice of low molecular weight heparin (LMWH) or fondaparinux, taking into account their clinical condition and comorbid medical problems.

Patients with severe renal impairment (estimated glomerular filtration rate <30ml/min/1.73 m2) should be offered unfractionated heparin (UFH). UFH should also be considered for those patients with an increased risk of bleeding.

For patients with PE and haemodynamic instability, thrombolytic therapy should be considered.

In cases where the patient is started on a vitamin K antagonist (VKA), the LMWH, fondaparinux or UFH should be continued until the international normalised ratio (INR) is 2 or above for at least 24 hours. The VKA should be continued for 3 months, at which time an assessment of the risks and benefits or continuing VKA treatment should be made.

In patients with an unprovoked PE, a VKA should be offered beyond 3 months.

In patients with active cancer and confirmed proximal DVT or PE, LMWH should be commenced and continued for 6 months. At 6 months the risks and benefits of continued anticoagulation should be assessed. VKA are not suitable in patients with active cancer due to an increased risk of recurrent venous thromboembolic events and an increased risk of anticoagulant-related bleeding. In addition cancer patients tend to have a poor appetite and take multiple medications related to their diseases which can lead to an erratic INR and difficulties with Warfarin dosing. Thus, in the question about the fourth stem is the most appropriate answer. knee length mother of the bride dresses