Dr Stephen Bolsin is the man widely credited with blowing the whistle on Bristol - endangering his own future in the process.

He claims he was virtually driven out of medicine in this country after proving the catalyst for the ensuing scandal.

But what drives a relatively junior consultant anaesthetist to take the extreme step of risking everything in this way?

Dr Bolsin's own words sum it up: "In the end I just couldn't go on putting those children to sleep, with their parents present in the anaesthetic room, knowing that it was almost certain to be the last time they would see their sons or daughters alive."

I got the impression he'd been told his career would be under threat if he persisted

Dr Andy Black, of Steve Bolsin

Campaigner Maria Shortis toldBBC News Online how she arranged to meet Bolsin on seeing him quoted in a newspaper in 1995.

Bolsin was doing the unthinkable - accusing his own team of failing the very babies it was trying to save.

She said: "When I read it, I thought: 'My God - this guy's just lost his job."

However, it had been a long journey to reach this point.

The young anaesthetist arrived from London's Royal Brompton Hospital in 1988.

He says he noticed almost straight away that operations seemed to be taking much longer in his new hospital.

He also suspected that death rates were higher - but had no firm evidence of this.

Confrontation

The young doctor raised the issue, briefly, in a letter to hospital trust chief executive Dr John Roylance.

There followed, he claimed, a confrontation