Graduated compression stockings for prevention of deep vein thrombosis during a hospital stay

Hospital patients can develop deep vein thrombosis (DVT) in the legs and pelvic veins immediately after surgery or if they are not mobile because of a medical illness. Symptoms vary from none to pain and swelling in the legs. A blood clot can move from the leg to the lungs, with the danger of pulmonary embolism (PE) and death. Usually the DVT clears up or has long-term effects such as high venous pressure in the leg, leg pain, swelling, darkening of the skin or inflammation.

DVT can be prevented using compression or drugs. Drugs may cause bleeding, which is a particular concern in surgical patients. Graduated compression stockings (GCS) help prevent blood clots forming in the legs by applying varying amounts of pressure to different parts of the leg. We identified 19 randomised controlled trials (2745 analytic units made up of 1681 individual patients and 1064 individual legs). Eight trials compared wearing stockings to no stockings and 10 compared stockings plus another method with that method alone in patients undergoing surgery. The other methods used were Dextran 70, aspirin, heparin, and mechanical sequential compression. Of the 19 trials, nine included patients undergoing general surgery, six included patients undergoing orthopaedic surgery, and only one trial included medical patients. The compression stockings were applied on the day before surgery or on the day of surgery and were worn up until discharge or until the patients were fully mobile. In the majority of the included studies DVT was identified by the radioactive I125 uptake test. Overall, included studies were of good quality.

Our review confirmed that GCS reduce the risk of DVT in hospitalised surgical patients. It also demonstrated that GCS may reduce the risk of developing DVT in the thighs (proximal DVT) and PE in such patients, though these results were based on a much smaller number of participants. The incidence of adverse effects and complications associated with wearing GCS was poorly reported in the included studies. Limited evidence was available for hospitalised medical patients, with only one study suggesting the effectiveness of GCS in preventing DVT in such patients.

Authors' conclusions: 

GCS are effective in diminishing the risk of DVT in hospitalised patients, with strong evidence favouring their use in general and orthopaedic surgery. However, evidence for their effectiveness in medical patients is limited to one trial.

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Background: 

One of the settings where deep vein thrombosis (DVT) in the lower limb and pelvic veins occurs is in hospital with prolonged immobilisation of patients for various surgical and medical illnesses. Using graduated compression stockings (GCS) in these patients has been proposed to decrease the risk of DVT. This is an update of a Cochrane review first published in 2000 and updated in 2010.

Objectives: 

To evaluate the effectiveness and safety of graduated compression stockings in preventing DVT in various groups of hospitalised patients.

Search strategy: 

For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched March 2014) and CENTRAL (2014, Issue 2).

Selection criteria: 

Randomised controlled trials (RCTs) involving GCS alone; or GCS used on a background of any other DVT prophylactic method. Results from both these groups of trials were combined in this update.

Data collection and analysis: 

For this update one review author (AS) extracted the data. These were cross-checked and authenticated by a second author (MJD). Two review authors (AS and MJD) assessed the quality of trials. Disagreements were resolved by discussion.

Main results: 

Nineteen RCTs were identified involving 1681 individual patients and 1064 individual legs (2745 analytic units). Of these 19 trials, nine included patients undergoing general surgery, six included patients undergoing orthopaedic surgery, and only one trial included medical patients. 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 patients were fully mobile. In the majority of the included studies DVT was identified by the radioactive I125 uptake test. Overall, included studies were of good quality.

In the treatment group (GCS) of 1391 units 126 developed DVT (9%) in comparison to the control group (without GCS) of 1354 units where 282 (21%) developed DVT. The Peto odds ratio (OR) was 0.33 (95% confidence interval (CI) 0.26 to 0.41) with an overall effect favouring treatment with GCS (P < 0.00001).

Based on results from eight included studies, the incidence of proximal DVT was 7 of 517 (1%) units in the treatment group and 28 of 518 (5%) units in the control group. The Peto OR was 0.26 (95% CI 0.13 to 0.53) with an overall effect favouring treatment with GCS (P = 0.0002). Based on results from five included studies, the incidence of PE was 5 of 283 (2%) participants in the treatment group and 14 of 286 (5%) in the control group. The Peto OR was 0.38 (95% CI 0.15 to 0.96) with an overall effect favouring treatment with GCS (P = 0.04). Limited data were available to accurately assess the incidence of adverse effects and complications with the use of GCS.