The aim of this commentary is to discuss from a rehabilitation perspective the recently published Cochrane Review “Graduated compression stockings for prevention of deep vein thrombosis” by Sachdeva et al. (https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD001484.pub4/full) which was developed by the Cochrane Vascular Group.1 This Cochrane Corner is produced in agreement with the American Journal of Physical Medicine & Rehabilitation by Cochrane Rehabilitation.
Patients in rehabilitation are often at risk for a deep venous thrombosis (DVT), condition associated to an increased morbidity, as pulmonary embolism and postthrombotic syndrome, and even mortality. Although rehabilitation populations are very heterogeneous, many of them combine several risk factors for venous thromboembolism, such as recent surgery or trauma, illness, immobilization, paralysis, and malignancy. There is not one overarching guideline for prevention of venous thromboembolism in rehabilitation patients, but mostly, low molecular weight heparin is prescribed in the acute phase.2 A Cochrane Review on the role of graduated compression stockings in the prevention of DVT in the hospital was recently updated.
Graduated Compression Stockings for Prevention of Deep Vein Thrombosis
(Sachdeva et al., 2018)
What Is the Aim of this Cochrane Review?
The aim of this Cochrane Review was to evaluate the effectiveness and safety of graduated compression stockings in preventing deep vein thrombosis in various groups of hospitalized patients.
What Was Studied in the Cochrane Review?
The population addressed in this review comprised patients of either sex and any age, hospitalized for conditions other than stroke. The intervention studied was the use of graduated compression stockings (GCS) for DVT prophylaxis. The intervention was compared with “no prophylaxis” and “no stockings on a background of another method of DVT prophylaxis in both the treatment and control group (eg, aspirin, heparin).” The primary outcome of the study was the diagnosis of DVT, either all DVT or proximal DVT, identified by ultrasound, venogram, or isotope studies. The secondary outcomes of the review were: (a) diagnosis of pulmonary embolism, identified by a ventilation perfusion lung scan, pulmonary angiogram, or post-mortem examination; and (b) complications and adverse effects arising from the use of GCS.
Search Methodology and Up-to-Dateness of the Cochrane Review?
This review is an update of a Cochrane Review first published in 2000 and updated in 2010 and 2014.
The Cochrane Vascular Specialized Register, CENTRAL, MEDLINE Ovid, Embase Ovid, CINAHL Ebsco, AMED Ovid, and trials registries were last searched on June 12, 2018. Furthermore, the authors searched the reference lists of all potentially eligible studies identified from the electronic searches to find additional trials.
What Are the Main Results of the Cochrane Review?
The review included 20 randomized controlled trials with a total of 1681 individual participants and 1172 individual legs (2853 analytic units). Of these 20 trials, 10 included patients undergoing general surgery; six included patients undergoing orthopedic surgery (mainly total knee and hip arthroplasty); three individual trials included patients undergoing neurosurgery (head or spinal pathology including trauma), cardiac surgery, and gynecological surgery, respectively; and only one trial included medical patients (myocardial infarction). Graduated compression stockings were applied on the day before surgery or on the day of surgery and were worn up until discharge or until the participants were fully mobile. In most included studies, DVT was identified by the radioactive I125 uptake test. Duration of follow-up ranged from 7 to 14 days. The included studies were at an overall low risk of bias. The review shows that wearing GCS reduced the overall risk of developing DVT, and probably also DVT in the thighs, and that GCS may reduce the risk of pulmonary embolism among patients undergoing surgery. Because only one trial included medical patients, results for this population are limited. The occurrence of problems associated with wearing GCS was poorly reported in the included studies.
How Did the Authors Conclude on the Evidence?
The authors concluded that there is high-quality evidence that GCS are effective in reducing the risk of DVT in hospitalized patients who have undergone general and orthopedic surgery, with or without other methods of background thromboprophylaxis, where clinically appropriate. They found moderate-quality evidence that GCS probably reduce the risk of proximal DVT and low-quality evidence that GCS may reduce the risk of pulmonary embolism. However, there remains a paucity of evidence to assess the effectiveness of GCS in diminishing the risk of DVT in medical patients.
What Are the Implications of the Cochrane Evidence for Practice in Rehabilitation?
This Cochrane Review supports the use of GCS in patients hospitalized for orthopedic surgery, general surgery, or neurosurgery and after myocardial infarction; patients after myocardial infarction and total hip or knee arthroplasty are of rehabilitation interest. We note that 19 of the 20 RCTs included in the review were performed between 1971 and 1996, after which only one more RCT was added, dating from 2009. This implies that in most of the studies diagnostics were different from the current criterion standard, which is duplex ultrasonography, which was only used in the most recent included study of 2009. In addition, pharmacological methods of prevention changed and have nowadays a lower risk profile and may be more user-friendly.
Thirty-five of the excluded studies, of which approximately half were published after 2000 did not have appropriate control arms. Patients with stroke were excluded from the search as a separate Cochrane Review focused on people with acute stroke, suggesting that GCS are less or not effective in stroke patients.3 The rationale for this is that stockings reduce the cross-sectional area of the deep veins, making the calf muscle pump more effective and thereby improving blood flow. The authors of the Clots in Legs Or sTockings after Stroke trials have suggested in 2009 that severe leg weakness in people with acute stroke may therefore account for the ineffectiveness of stockings in this patient group.4 In addition, GCS may have adverse effects in stroke patients, such as skin breaks, ulcers, blisters, and skin necrosis. However, in 2015, the Clots in Legs Or sTockings after Stroke 3 trial showed that intermittent pneumatic compression is an effective and inexpensive method of reducing the risk of DVT and improving survival in immobile stroke patients.5
Another physical agent in the field of prevention of DVT is neuromuscular electrical stimulation. In this regard, a Cochrane Review was published in 2017. The conclusion of the authors is that the best available evidence about the effectiveness of neuromuscular electrical stimulation in the prevention of venous thromboembolism is not adequately robust to allow definitive conclusions, but low-quality evidence suggested that neuromuscular electrical stimulation may be associated with a lower risk of DVT compared with no prophylaxis (moderate-quality evidence) and higher risk of DVT compared with low-dose heparin (low-quality evidence). Adequately powered high-quality randomized controlled trials are required to provide robust evidence.6
From a rehabilitation perspective, GCS seem effective in reducing the risk of DVT in hospitalized patients who have undergone surgery, with or without other methods of background thromboprophylaxis, if there is no contraindication, such as skin problems. Except for one included study on myocardial infarction, there is no evidence of sufficient quality for medical or neurological patients, such as those with stroke.
It has to be considered that in rehabilitation patients, there may also be other motives for wearing graduated compressive stockings, for example, to prevent edema in patients with paralysis of one or both lower limbs. In patients with spinal cord injury, GCS induce an enhanced sympathetic activity, and enhanced postexercise sympathetic activity with GCS may help prevent orthostatic hypotension or postexercise hypotension.7
Finally, we encourage future studies of a good design and using currently available diagnostic tools and drugs.
I thank Cochrane Rehabilitation and Cochrane Vascular Group for reviewing the contents of the Cochrane Corner.
1. Sachdeva A, Dalton M, Lees T: Graduated compression stockings for prevention of deep vein thrombosis. Cochrane Database Syst Rev
2. Kelly BM, Yoder BM, Tang CT, et al: Venous thromboembolic events in the rehabilitation setting. PM R
3. Naccarato M, Chiodo Grandi F, Dennis M, et al: Physical methods for preventing deep vein thrombosis in stroke. Cochrane Database Syst Rev
4. Dennis M, Sandercock PA, Reid J, et al:, CLOTS Trials Collaboration: Effectiveness of thigh-length graduated compression stockings to reduce the risk of deep vein thrombosis after stroke (CLOTS Trial 1): a multicentre, randomised controlled trial. Lancet
5. Dennis M, Sandercock P, Graham C, Forbes J, Smith JCLOTS (Clots in Legs Or sTockings after Stroke) Trials Collaboration: The Clots in Legs Or sTockings after Stroke (CLOTS) 3 trial: a randomised controlled trial to determine whether or not intermittent pneumatic compression reduces the risk of post-stroke deep vein thrombosis and to estimate its cost-effectiveness. Health Technol Assess
6. Hajibandeh S, Hajibandeh S, Antoniou GA, et al: Neuromuscular electrical stimulation for the prevention of venous thromboembolism. Cochrane Database Syst Rev
7. Rimaud D, Calmels P, Pichot V, et al: Effects of compression stockings on sympathetic activity and heart rate variability in individuals with spinal cord injury. J Spinal Cord Med