Are inflatable sleeves and medication effective to prevent deep vein thrombosis and pulmonary embolism after surgery?

Key message

• The use of inflatable sleeves worn on the legs (intermittent pneumatic leg compression) plus medication may reduce the rate of new cases of blood clots in the lungs and legs compared to inflatable sleeves alone.

• The use of inflatable sleeves plus medication compared to medication alone reduces the rate of new cases of blood clots in the legs and may reduce new blood clots in the lungs.

• The addition of a medication to inflatable sleeves, may increase the risk of bleeding compared to inflatable sleeves alone.

Why is this question important?

Deep vein thrombosis (DVT) and pulmonary embolism are collectively known as venous thromboembolism, and occur when a blood clot develops inside the leg veins and travels to the lungs. They are possible complications of staying in hospital after surgery, trauma or other risk factors. These complications extend hospital stay and are associated with long‐term disability and death. Patients undergoing total hip or knee replacement (orthopaedic) surgery or surgery for colorectal cancer are at high risk of venous thromboembolism. Sluggish blood flow, increased blood clotting and blood vessel wall injury are factors that make it more likely that people will experience a blood clot. Treating more than one of these factors may improve prevention. Mechanical intermittent pneumatic leg compression involves wrapping the legs with inflatable sleeves or using foot pumps. These put gentle pressure on the legs and its veins, reducing sluggish blood flow, while medications such as aspirin and anticoagulants reduce blood clotting. These medications are known as pharmacological prophylaxis (drugs used to prevent blood clots). However, these medications can also increase the risk of bleeding.  We wanted to find out if combining compression and medication to stop blood clots was more effective than either compression or medication alone.

What did we find?

We searched for studies that compared combined compression and medication against either compression or medication alone. We found 34 studies with a total of 14,931 participants. The mean age of participants, where reported, was 62.7 years. Most participants had either a high‐risk procedure or condition (orthopaedic surgery in 14 studies and urology, cardiothoracic, neurosurgery, trauma, general surgery, gynaecology or other types of participants in the remaining studies).

Compared to compression alone, compression plus medication was better by reducing the rate of new cases of pulmonary embolism (19 studies, 5462 participants). DVT was also reduced for compression combined with medication when compared with compression alone (18 studies, 5394 participants). The addition of a medication to compression, however, increased the risk of any bleeding compared to IPC alone, from 1% to 5.9%. Major bleeding followed a similar pattern, with an increase from 0.3% to 2.2%. Further analysis looking at different types of participants (orthopaedic and non‐orthopaedic participants) showed a similar risk for DVT. It was not possible to assess differences between subgroups for pulmonary embolism.

Compared with medication alone, combined compression and medication was better by reducing pulmonary embolism (15 studies with 6737 participants). DVT was also reduced in the combined compression and medication group (17 studies with 6151 participants). No differences were observed in rates of bleeding (six studies with 1314 participants). Further analysis looking at different subgroups of participants did not show any overall difference in incidence of pulmonary embolism or DVT between orthopaedic and non‐orthopaedic participants.

How certain are we in the evidence?

We found our confidence in the evidence ranged from high to very low. We had concerns on how the studies were carried out, because there were small numbers of clots overall and different definitions used for bleeding between the studies.

How up to date is this evidence?