Approaches for primary prevention include pharmacological prophylaxis (e.g., low molecular weight heparin [LMWH], unfractionated heparin, direct-acting oral anticoagulants, fondaparinux) and mechanical thromboprophylaxis (e.g., graduated compression stockings, intermittent pneumatic compression).
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The efficacy of inferior vena cava filters for the prevention of PE remains unclear.[68][69][70] Recent studies have found that primary prevention improves with a multi-faceted approach including computer alerts.[71]
The UK National Institute for Health and Care Excellence (NICE) gives specific recommendations for the primary prevention of venous thromboembolism (VTE) in several patient populations.[72]
Surgical patients
Interventions for people having abdominal surgery:[72]
Offer VTE prophylaxis to people undergoing abdominal (gastrointestinal, gynaecological, urological) surgery who are at increased risk of VTE.
Start mechanical VTE prophylaxis on admission for people undergoing abdominal surgery, with either anti-embolism stockings or intermittent pneumatic compression.
Add pharmacological VTE prophylaxis for ≥7 days for people undergoing abdominal surgery whose risk of VTE outweighs their risk of bleeding. This can be done with either LMWH or fondaparinux sodium.
Interventions for people having thoracic surgery:[72]
Consider VTE prophylaxis for people undergoing thoracic surgery who are at increased risk of VTE.
Start mechanical VTE prophylaxis on admission for people undergoing thoracic surgery, with either anti-embolism stockings or intermittent pneumatic compression.
Consider adding pharmacological VTE prophylaxis for ≥7 days for people undergoing thoracic surgery whose risk of VTE outweighs their risk of bleeding. Use LMWH as first-line or, if contraindicated, use fondaparinux sodium.
Interventions for people having head and neck surgery:[72]
Consider pharmacological VTE prophylaxis with LMWH for ≥7 days for people undergoing oral or maxillofacial surgery or ear, nose, or throat (ENT) surgery whose risk of VTE outweighs their risk of bleeding.
Consider mechanical VTE prophylaxis on admission for people undergoing oral or maxillofacial surgery or ENT surgery who are at increased risk of VTE and high risk of bleeding. This can be done with either anti-embolism stockings or intermittent pneumatic compression.
Interventions for people having cardiac surgery:[72]
Consider mechanical VTE prophylaxis on admission for people who are undergoing cardiac surgery who are at increased risk of VTE. Choose either anti-embolism stockings or intermittent pneumatic compression.
Consider adding pharmacological VTE prophylaxis for ≥7 days for people undergoing cardiac surgery who are not having other anticoagulation therapy. Use LMWH as first-line or, if contraindicated, use fondaparinux sodium.
NICE also makes recommendations for patients undergoing bariatric surgery, orthopaedic surgery, spinal or cranial surgery, and vascular surgery.[72] NICE also recommends that patients are advised to stop oestrogen-containing oral contraceptives or hormone replacement therapy 4 weeks before elective surgery and that advice on alternative methods should be provided.[72]
Acutely ill medical patients:[72]
Offer pharmacological VTE prophylaxis for ≥7 days to acutely ill medical patients whose risk of VTE outweighs their risk of bleeding. Use LMWH as first-line or, if contraindicated, use fondaparinux sodium.
Acute stroke patients:[72]
Do not offer anti-embolism stockings for VTE prophylaxis.
Consider intermittent pneumatic compression for people admitted with acute stroke who are immobile (and start within 3 days of acute stroke).
Pregnancy
LMWH is recommended for the prevention of VTE in pregnant women, and in women who gave birth or had a miscarriage or termination of pregnancy in the past 6 weeks who are admitted to hospital and whose risk of VTE outweighs their risk of bleeding. This does not apply to those in active labour where VTE prophylaxis should not be started or should be stopped.[39][72]
People with cancer
Routine pharmacological prophylaxis is not recommended for outpatients with cancer who have no additional risk factors for VTE.[72][73] There are some circumstances where VTE prophylaxis should be considered, such as people receiving chemotherapy for myeloma or pancreatic cancer; further details on this are given in the NICE guidance.[72]
Long-distance travel
The British Society for Haematology does not recommend the use of graduated compression stockings or pharmacological thrombophylaxis in long-distance (>4 hours) travellers. Those travellers at increased risk of VTE (e.g., recent surgery or trauma, active malignancy, pregnancy, severe immobility, previous unprovoked VTE and no longer on anticoagulants) should consider using pharmacological thromboprophylaxis with or without graduated compression stockings for travel more than 4 hours.[36] Compression stockings should be properly fitted, below-knee, and graduated, and provide 15 to 30 mmHg of pressure at the ankle during travel. During travel, people at increased risk of VTE should move or walk about frequently, exercise their calf muscles, and sit in an aisle seat (if possible).