What are the guidelines for deep vein thrombosis (DVT) prophylaxis and treatment, as well as pulmonary embolism (PE) treatment?

DVT Prophylaxis and Treatment Guidelines, and PE Management

For hospitalized patients with active malignancy and acute medical illness or reduced mobility, pharmacologic thromboprophylaxis is strongly recommended in the absence of bleeding or other contraindications. 1

DVT Prophylaxis

Hospitalized Medical Patients

• Hospitalized patients with active malignancy without additional risk factors may be considered for pharmacologic thromboprophylaxis in the absence of bleeding or contraindications 1
• Pharmacologic prophylaxis options include:
  • Unfractionated heparin (UFH): 5,000 U subcutaneously every 8 hours 1
  • Dalteparin: 5,000 U subcutaneously once daily 1
  • Enoxaparin: 40 mg subcutaneously once daily 1
  • Fondaparinux: 2.5 mg subcutaneously once daily 1

Surgical Patients

• For surgical patients, prophylaxis options include:
  • UFH: 5,000 U 2-4 hours preoperatively and every 8 hours thereafter 1
  • Dalteparin: 2,500 U 2-4 hours preoperatively and 5,000 U once daily thereafter 1
  • Enoxaparin: 20 mg 2-4 hours preoperatively and 40 mg once daily thereafter 1
  • Fondaparinux: 2.5 mg once daily beginning 6-8 hours postoperatively 1

Special Considerations

• Low-molecular-weight heparins (LMWH) or fondaparinux are preferred over IV unfractionated heparin for most patients 1
• Avoid LMWHs in patients with creatinine clearance <30 ml/min 1
• Mechanical prophylaxis with graduated compression stockings is not recommended as monotherapy except when pharmacological methods are contraindicated 1
• Routine prophylaxis is not recommended for patients admitted for minor procedures or short chemotherapy infusion 1

DVT Treatment

Initial Treatment

• For acute DVT, initial parenteral anticoagulant therapy is recommended 1
• Treatment options include:
  • UFH: 80 U/kg IV bolus, then 18 U/kg/h IV infusion (adjusted to achieve aPTT ratio 1.5-2.5) 1
  • Enoxaparin: 1 mg/kg subcutaneously twice daily or 1.5 mg/kg once daily 1
  • Dalteparin: 100 U/kg subcutaneously every 12 hours or 200 U/kg once daily 1
  • Fondaparinux: Weight-based dosing (<50 kg: 5 mg; 50-100 kg: 7.5 mg; >100 kg: 10 mg) subcutaneously once daily 1
  • Rivaroxaban: 15 mg orally twice daily for 21 days, then 20 mg once daily 2, 1
  • Apixaban: 10 mg orally twice daily for 7 days, followed by 5 mg twice daily 3, 1

Long-term Treatment

• For a first proximal DVT provoked by surgery or transient risk factor: 3 months of therapy 1
• For unprovoked DVT: Consider extended therapy if bleeding risk is low or moderate 1
• For cancer-associated DVT: Extended therapy with LMWH preferred over vitamin K antagonists 1
• For recurrent VTE: Extended anticoagulant therapy 1
• For standard vitamin K antagonist therapy: Target INR 2.0-3.0 1

Pulmonary Embolism (PE) Management

Diagnosis

• Diagnosis should be based on clinical probability assessment using validated tools (e.g., Wells score) 1
• D-dimer testing is recommended for patients with low or intermediate clinical probability 1
• Computed tomography pulmonary angiography (CTPA) is the preferred imaging modality for diagnosis 1

Treatment

• Initial treatment options are the same as for DVT 1
• For PE with hypotension (high-risk PE), systemic thrombolytic therapy is recommended 1
• For intermediate or low-risk PE, routine systemic thrombolysis is not recommended 1
• Treatment duration:
  • First PE provoked by surgery or transient risk factor: 3 months 1
  • Unprovoked PE: Consider extended therapy if bleeding risk is low or moderate 1
  • Cancer-associated PE: Extended therapy with LMWH preferred 1

Special Situations

• For pregnant patients with suspected PE:
  • Use therapeutic, fixed doses of LMWH based on early pregnancy weight 1
  • Do not use DOACs during pregnancy or lactation 1
• For chronic thromboembolic pulmonary hypertension (CTEPH):
  • Extended anticoagulation is recommended 1
  • Consider pulmonary thromboendarterectomy for selected patients 1

Key Considerations and Pitfalls

• Renal function: Adjust or avoid LMWH and fondaparinux in patients with severe renal impairment (CrCl <30 ml/min) 1
• Bleeding risk: Always assess bleeding risk before initiating anticoagulation 1
• Cancer patients: LMWH is preferred over vitamin K antagonists for long-term therapy 1
• DOACs: Avoid in patients with severe renal impairment, antiphospholipid antibody syndrome, or pregnancy 1, 3, 2
• Inferior vena cava filters: Not recommended for routine use; consider only when anticoagulation is contraindicated 1, 4
• Follow-up: Routinely re-evaluate patients 3-6 months after acute PE 1

Emerging Evidence

• Recent studies suggest similar efficacy between UFH and LMWH for VTE prophylaxis in ICU patients, though LMWH may be associated with lower mortality 5
• Home treatment with LMWH for DVT is safe and effective in selected patients, reducing hospitalization time 6
• DOACs are now considered first-line therapy for many patients with VTE due to convenience and comparable efficacy to traditional therapy 3, 2, 4