Category: Advancing Modules

• The CLOTS 3 trial was a large multi-centre randomised trial which recruited patients in 94 UK hospitals
• The primary outcome was a proximal (above knee) DVT by 30 days
• Patients were also followed up to identify any DVT, PE for the first 6 months
• Also to measure survival, disability and quality of life at 6 months

• A large number of small randomised trials have shown that IPC reduced the risk of DVT in patients undergoing surgery.
• The CLOTS 3 trial has shown that IPC reduces the risk of DVT in immobile stroke patients.
• The CLOTS 3 trial also suggested that stroke patients treated with IPC have a greater chance of surviving.
  CLOTS 3 trial results paper. CLOTS trial 3 (secondary analyses)
• SIGN guidelines now recommend that use of IPC should be considered in immobile stroke patients

• small trials in surgical patients, where stockings can be applied before immobility, have suggested that they reduce the risk of DVT
• however the large CLOTS 1 trial has conclusively shown that graduated compression stockings do not reduce the risk of DVT after stroke
• they are difficult to fit, apply and maintain
• patients find them uncomfortable
• they cause pressure sores and skins problems in 5% of patients
• they waste valuable nursing resources
• NICE and ESO VTE guidelines recommend that GCS should not be used in stroke patients

CLOTS Trials Collaboration. Effectiveness of thigh-length graduated compression stockings to reduce the risk of deep vein thrombosis after stroke. Reference: (CLOTS Trial 1): a multicentre, randomized controlled trial. Lancet 2009;373:1958-1965. CLOTS Trial 1 paper. CLOTS Trial 1 content from STARs Advancing Module 11. CLOTS trial design

Before starting a patient on prophylactic heparin or low molecular weight heparin the risk (bleeding) and benefits (avoiding DVT and PE) need to be carefully considered. Identifying patients who will definitely benefit from anticoagulation is not easy.

These do reduce the risk of DVT but:

• They significantly increase the risk of important bleeding
• No significant reduction in deaths
• No improvement in functional outcomes
• They are not recommended for routine use after stroke by Intercollegiate (NICE) OR ESO VTE guidelines for ischaemic stroke
• LMWH may be used in patients at high risk of DVT AND low risk of bleeding
• But unclear how these are defined

Reference:

Lederle FA, Zylla D, MacDonald R, Wilt TJ. Venous Thromboembolism Prophylaxis in Hospitalized Medical Patients and Those With Stroke: A Background Review for an American College of Physicians Clinical Practice Guideline. Ann Intern Med 2011;155:602-615. Link to paper.

Aspirin is given to most patients with an ischaemic stroke because it has been shown to reduce the risk of recurrence and a poor outcome (death or disability). The first International Stroke trial (IST-1) also showed that the risk of pulmonary embolism was reduced slightly.

The International Stroke Trial, 1997.

ESO VTE guidelines for ischaemic stroke