Effective Prophylaxis for Deep Venous Thrombosis After Stroke
Both Low-Dose Anticoagulation and Stockings for Most Cases
Geoffrey A. Donnan MD, FRACP Section Editors: Stephen M. Davis MD, FRACP
What are the factors that underline the benefits achieved by stroke unit care? Although incompletely understood, an increased adherence to a range of processes of care is important.1 Many of these processes are directed at the prevention of poststroke complications. Among the most important of these is prophylaxis against deep venous thrombosis (DVT) and pulmonary embolism. Although there have been a number of small trials in stroke patients demonstrating the relative safety and usefulness of low-dose anticoagulants, the evidence base is relatively small, as pointed out by Dennis.2 Both protagonists consider that in patients at very high risk, there is no debate, and low-dose heparin or low-molecular-weight heparin/heparinoids should be used. Nonetheless, it would appear that Adams would advocate anticoagulation more often. Interestingly, neither seems to favor stockings as routine. Although relatively uncommon in stroke, most of us will have managed patients who are about to go from acute care to a rehabilitation unit, and who suddenly deteriorate because of life-threatening pulmonary embolism.
The risk of low-dose anticoagulation, specifically the development of symptomatic hemorrhagic transformation, appears to be quite low. The accumulated evidence for this is now quite strong.2 Although Dennis draws attention to the discomfort and potential risks of stocking use, we find that they are generally well-tolerated. Systematic overview shows that graduated compression stockings are effective in diminishing the risk of DVT in hospitalized patients, even more so when combined with a form of antithrombotic therapy.3
What do we do in our practice? We recognize the inadequacy of the evidence in guiding clinical practice and look forward to the completion of trials such as CLOTS and new DVT prevention trials using low-dose anticoagulation. At present, we routinely use below-knee stockings in most stroke patients in our Stroke Care Units and use this as a quality indicator of the unit performance. In patients at higher risk, particularly those who are difficult to mobilize or have major leg weakness, we use a combination of stockings and low-dose anticoagulation. We also apply these principles to patients with intracerebral hemorrhage, but only after their conditions have stabilized. There is also uncertainty about the type of anticoagulation. Following an earlier small trial,4 a larger study is comparing unfractionated heparin with a low-molecular-weight heparin.5 Direct thrombin inhibitors, such as ximelagatrin, might have a role in the future.6 On this occasion, while awaiting more evidence, we favor a more aggressive approach.
- Received July 19, 2004.
- Accepted July 26, 2004.
Cadilhac DA, Ibrahim J, Pearce DC, Ogden KH, McNeill J, Davis SM, Donnan GA. A multi-center comparison of processes of care between Stroke Units and conventional care wards in Australia. Stroke. 2004; 35: 1035–1040.
Counsell C, Sandercock P. Low-molecular-weight heparins or heparinoids versus standard unfractionated heparin for acute ischaemic stroke (Cochrane Review). In: The Cochrane Library. Chichester, UK: John Wiley & Sons, Ltd; 2004: 2.
Amaragiri SV, Lees TA. Elastic compression stockings for prevention of deep vein thrombosis (Cochrane Review). In: The Cochrane Library, Chichester, UK: John Wiley & Sons, Ltd; 2004: 2.
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