Mr Smeaton received a Queen's Gallantry medal after the airport attack
The prime minister has telephoned his support to the family of car bomb hero John Smeaton, who remains in a hospital intensive care unit.
Mr Smeaton, 32, who helped foil the attack on Glasgow airport in June last year, suffered a serious asthma attack on Thursday night.
He has been in "stable" condition in the Royal Alexandra hospital in his home town of Paisley ever since.
His fiance Christy MacPhedran has flown in from the US to be by his bedside.
Mr Smeaton has met Prime Minister Gordon Brown several times after being catapulted to fame when he told reporters covering the aftermath of the attack: "This is Glasgow, you know - we'll set about you."
The former airport baggage handler was publicly congratulated by Mr Brown at the Labour Party conference in Bournemouth last year.
Mr Smeaton has written about his health in his national newspaper column, and told Asthma Magazine earlier this year how an asthma attack when he was 19 caused him to tear a lung.
Bilal Abdulla, 29, and Mohammed Asha, 28, went on trial at Woolwich Crown Court, south-east London, on Thursday accused of attempting to murder hundreds of people with car bombs in London and Glasgow. They deny all the charges against them.
Mr Smeaton is in the hospital where Mr Abdulla was working as a junior house officer in general surgery at the time of the airport attack.