More than 10,000 lives could be saved each year under plans to screen everybody going into hospital for blood clots, a watchdog claims.
The National Institute for Health and Clinical Excellence (Nice) published guidance setting out how patients should be assessed for the clots, which kill an estimated 25,000 people admitted to wards in England each year.
It comes after chief medical officer Sir Liam Donaldson announced in 2008 that all patients admitted to hospital should be screened.
Doctors are being told to take action to reduce the risk of clots developing, which can often strike without warning.
Measures include giving patients compression stockings, blood-thinning drugs such as heparin or using foot pumps to keep blood circulating.
The focus of the guidance is on those clots that occur in veins, most commonly in the leg, called deep vein thrombosis (DVT).
Professor Tom Treasure, who chaired the guideline development group, described blood clots as a "silent killer".
He said doctors should be assessing people with a view to offering some sort of treatment or device, with even just one risk factor "triggering the question" of whether treatment is needed.
"It doesn't oblige the doctor to give treatment but it should ring an alarm bell," he said.
"I think it's an opt out situation. If you tick this box, what's your reason for not giving treatment? The default position should be giving (treatment)."
