Venous thromboembolism: reducing the risk for patients in hospital – NICE guideline

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This National Institute for Health and Care Excellence (NICE) guideline covers assessing and reducing the risk of venous thromboembolism (VTE or blood clots) and deep vein thrombosis (DVT) in people aged 18 and over in hospital. It aims to help healthcare professionals identify people most at risk of VTE. It describes treatments and interventions that can be used to prevent VTE.

Key recommendations

Assessing the risks of VTE and bleeding

  • Assess all patients on admission to identify those who are at increased risk of VTE. [2010]
  • Regard medical patients as being at increased risk of VTE if they:
    • have had or are expected to have significantly reduced mobility for 3 days or more or
    • are expected to have ongoing reduced mobility relative to their normal state and have one or more of the risk factors shown in box 1. [2010]
  • Regard surgical patients and patients with trauma as being at increased risk of VTE if they meet one of the following criteria:
    • surgical procedure with a total anaesthetic and surgical time of more than 90 minutes, or 60 minutes if the surgery involves the pelvis or lower limb
    • acute surgical admission with inflammatory or intra‑abdominal condition
    • expected significant reduction in mobility
    • one or more of the risk factors shown in box 1. [2010]
  • Assess all patients for risk of bleeding before offering pharmacological VTE prophylaxis [3]. Do not offer pharmacological VTE prophylaxis to patients with any of the risk factors for bleeding shown in box 2, unless the risk of VTE outweighs the risk of bleeding. [2010]
  • Reassess patients' risks of bleeding and VTE within 24 hours of admission and whenever the clinical situation changes, to:
    • ensure that the methods of VTE prophylaxis being used are suitable
    • ensure that VTE prophylaxis is being used correctly
    • identify adverse events resulting from VTE prophylaxis. [2010]

Reducing the risk of VTE

  • Encourage patients to mobilise as soon as possible. [2010]
  • Offer pharmacological VTE prophylaxis to general medical patients assessed to be at increased risk of VTE (see section 1.1). Choose any one of:
    • fondaparinux sodium
    • low molecular weight heparin (LMWH)[4]
    • unfractionated heparin (UFH) (for patients with severe renal impairment or established renal failure). [2010]
  • Start pharmacological VTE prophylaxis as soon as possible after risk assessment has been completed. Continue until the patient is no longer at increased risk of VTE. [2010]

Patient information and planning for discharge

  • Before starting VTE prophylaxis, offer patients and/or their families or carers verbal and written information on:
    • the risks and possible consequences of VTE
    • the importance of VTE prophylaxis and its possible side effects
    • the correct use of VTE prophylaxis (for example, anti‑embolism stockings, foot impulse or intermittent pneumatic compression devices)
    • how patients can reduce their risk of VTE (such as keeping well hydrated and, if possible, exercising and becoming more mobile). [2010]
  • As part of the discharge plan, offer patients and/or their families or carers verbal and written information on:
    • the signs and symptoms of deep vein thrombosis and pulmonary embolism
    • the correct and recommended duration of use of VTE prophylaxis at home (if discharged with prophylaxis)
    • the importance of using VTE prophylaxis correctly and continuing treatment for the recommended duration (if discharged with prophylaxis)
    • the signs and symptoms of adverse events related to VTE prophylaxis (if discharged with prophylaxis)
    • the importance of seeking help and who to contact if they have any problems using the prophylaxis (if discharged with prophylaxis)
    • the importance of seeking medical help and who to contact if deep vein thrombosis, pulmonary embolism or another adverse event is suspected. [2010]

[3] Prescribers should consult the summary of product characteristics for the pharmacological VTE prophylaxis being used or planned for further details.

[4] At the time of publication (June 2015) some types of LMWH do not have UK marketing authorisation for VTE prophylaxis in medical patients. Prescribers should consult the summary of product characteristics for the individual LMWH. Informed consent for off‑label use should be obtained and documented.

VTE is an important cause of death in hospital patients, and treatment of non‑fatal symptomatic VTE and related long‑term morbidities is associated with considerable cost to the health service.

The risk of developing VTE depends on:

  • the condition and/or procedure for which the patient is admitted and
  • any predisposing risk factors, such as:
    • age
    • obesity
    • concomitant conditions.

This guideline makes recommendations on assessing and reducing the risk of VTE in patients in hospital. It offers guidance on the most clinically and cost‑effective measures for VTE prophylaxis in these patients. The recommendations take into account the potential risks of the various options for prophylaxis and patient preferences.

You can read the guideline on NICE's website.