NHS boss Sir David Nicholson has rejected calls for him to quit and insisted he is "absolutely determined" to lead the organisation through the coming health reforms.
Sir David warned that the NHS is currently at "maximum risk" and insisted his experience meant he was "absolutely the right person" to be in charge during the transformation.
The NHS chief executive has faced calls to quit in the wake of a damning report into serious failings at Mid Staffordshire NHS Foundation Trust.
He was in charge of the strategic health authority (SHA) for part of the time when patients were mistreated and potentially hundreds died needlessly because of neglect.
Sir David, in evidence to the Health Select Committee, said he would not go back on his vow to see through the Government's radical reforms despite the criticism.
"I said two years ago that I would take the responsibility of leading the NHS through this enormously complex set of changes," he told MPs.
"I promised both the Government and the NHS that I would see that through and I am absolutely determined to do that over the next period."
Sir David (centre) flanked by Sir Bruce Keogh and Liz Redfern Sir David denied he was just a "process man" but admitted patients had been sidelined across the NHS at the time of the scandal because of changes being pushed through.
"I put my hands up to that and I was a part of that, but my learning from that was to make sure it doesn't happen again," he said.
He stressed that, although he was responsible for three strategic health authorities, trusts like Mid-Staffordshire were in control of their own hospitals.
The chair of the SHA had never raised concerns with him about the standard of care and that the wider health authority had "no idea" what was going on, he added.
"I was running three [hospitals] and at the time I was responsible for national work on HR. The amount of time I could spend in each individual one was limited," he said.
Sir David admitted he visited Stafford Hospital during the time of the problems but said he was not alerted to any neglect or poor care, and also had no access to mortality rates.
And he pointed out that many senior figures at Mid-Staffs did go in the wake of the scandal so "it is not true to say that people weren't held to account".
Tory MP and GP Sarah Wollaston asked: "How far do you take personal responsibility for an organisation that has been shown to minimise patient complaints, to gag whistleblowers, to massage mortality data, and bury bad news and frankly to lose sight of the patient in the bed?"
Sir David rejected the description and said: "I have spent 35 years being a chief executive in the NHS and I am completely dedicated to improving services for patients.
"Of course when I hear bad stories about the NHS, of course I feel responsible. I have got the privileged position when I can try and do something about it which it seems to me is what I need to focus my attention on."
Sir David has faced calls to quit because of the Stafford Hospital scandal Amid concerns about clinical staff being gagged to stop them blowing the whistle over patient safety, he insisted the practice was unacceptable and illegal.
"If they want my permission to speak out in public - speak out. Because we will protect them in whatever way we need to do," he said.
Sir David also expressed regret that he had not personally met Cure The NHS campaigners when they first raised concerns about Mid Staffordshire.
But campaigner Julie Bailey, who started the group after her mother Bella died at Stafford Hospital in 2007, said his evidence had been "shameful" and called him an "absolute disgrace".
"He is the chief executive of the NHS. He is paid an awful lot of money to ensure that the NHS is well-managed. He has failed so he needs to resign," she told Sky News.
"In any other profession, he would have been sacked. We are talking about hundreds of people here who have lost their lives - lost their lives years ago and we are still here today fighting for accountability."
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