A daily pill could dramatically cut the 30,000 deaths caused by blood clots in hospitals each year, according to a study published in the Lancet medical journal today.

The number of post-surgery deaths from blood clots or venous thromboembolism (VTE) in hospitals each year is higher than the number of deaths caused by breast cancer, Aids and road traffic accidents - yet health professionals argue they are preventable and avoidable.

A report by England's chief medical officer Sir Liam Donaldson said around 25,000 people a year died from the condition in hospitals in England and Wales. The figure for the UK as a whole is estimated to be around 30,000. Sir Liam added "there was significant room for improvement".

Patients aged 60 and over, with a history of congenital heart disease and a family or personal history of blood clots, are considered to be in the at-risk group. Patients undergoing surgery are particularly likely to develop blood clots, with one-third of patients who are readmitted suffering deep vein thrombosis.

Dabigatran, developed by German pharmaceutical giant Boehringer Ingelheim, has been submitted to European authorities for approval of its primary use to prevent VTE following major orthopaedic surgery, such as total knee or hip replacements.

It is also being evaluated in an extensive global clinical trial programme and is considered a potential treatment for stroke prevention.

Clinical trials have shown the drug can be given in a fixed oral dose, acts quickly with limited side effects and has little interaction with food or other prescribed drugs, while it has a predictable and consistent anticoagulation effect without need for monitoring.

Thrombosis or blood clots can form when people are sitting for long periods in one place, especially where the legs may be cramped or circulation restricted.

According to the trial, Dabigatran, available early next year, is as effective as the current treatment, enoxaparin, that has to be injected and administered by a healthcare professional or patients willing to self-inject.

A much more convenient treatment, Dabigatran will be the first medicine available as a pill for these patients, many of who are elderly and unable to self-inject.

Recently published evidence highlighted the average time for a patient who has undergone a total hip replacement going on to develop a blood clot was 21 days. For three-quarters of patients this was after they had been discharged from hospital.

Professor Simon Frostick, professor of orthopaedics at the University of Liverpool and author of the Lancet study, said: "Given the trend for shorter hospital stays following joint replacement surgery, it is becoming increasingly important to have anticoagulant treatments available, which are safe and easy to use in an out-patient setting."

He added: "Based on the encouraging results demonstrated in the trial, once daily oral Dabigatran may be an attractive alternative to other regimens currently used to prevent VTE in patients undergoing hip replacement surgery."

Dr Beverley Hunt, medical director for thrombosis charity Lifeblood, said thrombosis is "a hidden, silent epidemic".