DVT Risk in Wheelchair Users: What It Is, What Raises It, and How to Reduce It

A blood clot in a deep vein (deep vein thrombosis, or DVT) is more common in wheelchair users than in the general population. It can develop without obvious symptoms. Here is what you need to know.

A blood clot that forms in one of the deep veins, usually in the leg (deep vein thrombosis, or DVT), can cause pain and swelling. It can also cause no symptoms at all. The serious risk with DVT is that the clot can break loose and travel to the lungs, causing a blockage in the lung's blood vessels (a pulmonary embolism), which is a medical emergency. Understanding this risk, and what reduces it, is genuinely important for wheelchair users.

Why wheelchair users are at higher risk

Blood clots form because of three factors working together: slow blood flow, changes to the blood vessel walls, and blood that clots more easily than normal.

Prolonged sitting in a wheelchair contributes to the first of these directly. When the leg muscles are inactive, they are not performing their usual role as pumps, contracting rhythmically to push blood back up toward the heart. Without this muscular action, blood pools in the lower legs and veins, flows more slowly, and is more likely to clot.

For wheelchair users whose lower limbs are less active, this effect is often stronger. The muscle pump in the legs may be working at reduced capacity, or not working at all.

Other risk factors are common among wheelchair users too. These include not drinking enough fluids (dehydration, which makes the blood thicker), long periods of travel without moving, a previous DVT, certain medications, smoking, and being overweight. Underlying health conditions, including heart and circulation problems and some inflammatory conditions, can also raise the risk.

Recognising the signs

DVT does not always cause obvious symptoms, which is part of what makes it dangerous. When symptoms do occur, they usually affect one leg. They can include swelling, a persistent ache or pain (particularly in the calf), warmth, and redness or a change in skin colour.

A blockage in the lung's blood vessels (a pulmonary embolism) causes sudden breathlessness, chest pain that may get worse with deep breathing, and a rapid heart rate. It can also cause coughing, sometimes with blood, and light-headedness or collapse. This is a medical emergency: call 999 immediately.

If you notice swelling or persistent pain in one leg for no clear reason, contact a GP promptly rather than waiting to see if it settles.

What reduces the risk

• Movement throughout the day. Moving your upper body, and any lower limb movement you can manage, breaks up long periods of sitting still and helps blood flow. Even passive movement of the feet and ankles, where possible, helps push blood back up toward the heart.
• Compression. Special stockings (compression stockings) may help reduce blood pooling in the veins and reduce swelling. They're sometimes recommended for people with vein problems (venous disease) or other DVT risk factors. A GP or nurse can advise whether they're right for you and, if so, the correct grade and fit.
• Hydration. Drinking enough fluids keeps your blood at a normal thickness (viscosity). Not drinking enough (dehydration) makes blood more likely to clot. Pale yellow urine is a sign that you're drinking enough.
• Leg elevation where possible. Raising your legs from time to time reduces blood pooling in the lower limbs. Even brief periods with your legs at or above heart level help blood flow back toward the heart (venous return).
• Anticoagulation medication. For people at high DVT risk, particularly those with a history of previous clots or significant immobility, a GP may recommend blood-thinning medication (anticoagulant medication) to help prevent clots. This is a clinical decision, based on weighing up the overall risks and benefits for that person.
• Long journeys. On long car, train, or air journeys, it's particularly important to take regular breaks to move, wear compression if advised, stay hydrated, and do upper body and any available lower limb exercises.

When to seek advice

If you haven't previously discussed DVT risk with a GP or specialist, it's worth raising at your next appointment, particularly if you have other risk factors. Your risk profile, and whether any preventative measures would help, is worth talking about before a problem occurs, not just afterwards.

This article is for general health information purposes and does not constitute medical advice. If you experience sudden unexplained leg swelling, pain, breathlessness, or chest pain, seek medical attention immediately. If you have concerns about DVT risk, please speak with a healthcare professional.