NHS chief Gary Walker 'knew about problems at Mid Staffordshire hospital for FOUR YEARS' Sir David is already under fire after the Mid Staffordshire NHS Trust scandal United Lincolnshire Hospital Trust is now being investigated over poor care Walker 'threatened with legal action because of BBC R4 interview he gave' Former health sec. Stephen Dorrell slams 'corrupt' culture of NHS gagging By Claire Ellicott, Sophie Borland, Mark Duell and Steve Robson NHS boss Sir David Nicholson was warned four years ago about problems at a trust which is being investigated for persistently high death rates, a whistleblower has claimed. It comes as a leaked letter from a doctor alleged a patient being treated at the same trust died after a surgeon was forced to perform three "radical procedures" on the same day due to "target pressure." The letter raised further concerns about the under-fire United Lincolnshire Hospitals NHS Trust and said an "otherwise well patient" had died two days after an operation, reported the Daily Telegraph. Meanwhile whistleblower Gary Walker - sacked in 2010 as chief executive of United Lincolnshire Hospitals - said Sir David ignored him when he raised concerns about patient safety in 2009. The trust is one of 14 being investigated by health chiefs over high mortality rates in the wake of the public inquiry report into serious failures at Mid Staffordshire NHS Foundation Trust. Julie Bailey, who set up the campaign group Cure the NHS after her mother Bella died at Stafford Hospital in 2007, said Mr Walker's comments made Sir David's position untenable. And union Unite called for Sir David's resignation, saying he presided over a "culture of fear and bullying" in the health service. Sir David, who was chief executive of the West Midlands Strategic Health Authority between August 2005 and April 2006 - at the height of the troubles in Mid Staffordshire - and is now head of the NHS Commissioning Board, has ignored calls for his resignation. When asked if she thought Sir David's position was now untenable, Miss Bailey agreed and said: "It is a clear indication that David Nicholson does not take patient safety as a priority - like at Mid Staffs. We do not know how many people lost their lives at United Lincolnshire but there were hundreds who lost their lives at Mid Staffs because of his lack of action. This is a clear indication that the NHS is using public money to gag people who wish to raise concerns about patient safety and a clear indication that David Nicholson knew about it. Rachael Maskell, head of health at union Unite, added: "Today, we call again for Sir David Nicolson, at last, to accept that he has presided over a culture of fear and bullying in the NHS in recent years and that he acknowledges that this regime, which has damaged patient care, has been cruelly exposed. He should resign. But last week, Sir David said he was "not ashamed" of being in his job following the publication of the Francis Report highlighting the "appalling and unnecessary suffering" of hundreds of patients at Mid Staffordshire between 2005 and 2009. Mr Walker was sacked in 2010 for gross professional misconduct over alleged swearing at a meeting. He claims he was forced to quit for refusing to meet Whitehall targets for non-emergency patients and was then gagged from speaking out as part of a settlement deal. Mr Walker said the trust came under pressure because of soaring demand for emergency beds. Because of the rising demand he felt like he needed to abandon the Government target of treating non-emergency cases within 18 weeks. He said Dame Barbara Hakin, who was then head of the East Midlands strategic health authority and is now national director for commissioning development at the NHS Commissioning Board, ordered him to meet the national targets regardless of demand. "The pressure I came under from Barbara Hakin specifically was, and I quote, "to meet the targets whatever demand,"" he told BBC Radio 4's Today programme. That is a dangerous thing to be saying in a situation where the hospitals are so full that you just don't have any beds for most of the day. 'This is a culture of fear, a culture of oppression - of information that's either going to embarrass a civil servant or embarrass a minister. These are big problems Gary Walker, former United Lincolnshire Hospital Trust chief executive The authority told the BBC it "utterly refuted" Mr Walker's claims and acted at all times "in the interest of patients." Mr Walker told the programme he accepted a so-called "supergag" as part of a settlement package of an unfair dismissal claim - reported to be at least £500,000 - to protect his family. Last week's damning Francis report into the Mid Staffs scandal recommended a ban on gagging orders imposed on NHS whistleblowers and Mr Walker's case has been raised in the Commons. Unite said that Mr Walker's case demonstrated the need for stronger whistleblowing systems. Ms Maskell said: "The chickens are coming home to roost for those that presided over a culture of fear and bullying across the NHS. Health secretary Jeremy Hunt needs to set up a system of robust whistleblowing procedures immediately in light of last week's Francis report and this latest shameful gagging episode. Gagging clauses should be outlawed. Mr Walker sensationally broke his silence to reveal he was driven from his job after warning Sir David that patients were in danger as long as four years ago. He received £500,000 hush money to prevent him going public with his fears that the "target culture" at the United Lincolnshire Hospitals trust could cost lives - and was reportedly threatened with legal action because of an interview he gave to BBC Radio 4 this morning. Sir David said last week he was "not ashamed" to remain in his job despite calls to quit from relatives of those who died because of his failure to take action during his time as a regional watchdog seven years ago. A Department of Health spokesman said allegations of the nature described by Mr Walker were taken 'extremely seriously'. 'In 2009, Sir David commissioned an independent review to look at Gary Walker's claims of bullying and harassment by East Midlands SHA,' the spokesman said. 'The review concluded there was no evidence whatsoever to back his claims and a summary of the review's findings and Sir David's response has been published publicly. 'Following concerns about the Trust in 2009, Dame Catherine Elcoat, the SHA's Director of Nursing carried out a full review into the quality of services. The review concluded there were no immediate concerns in respect of either patient safety or experience,' the spokesman added. If you consider that the people that have been running the NHS have created that culture of fear, they need either to be held to account or new people need to be brought in to change that culture Mr Walker also told BBC Radio 4's Today this morning: "It's a simple decision: you have emergency care or you have care that could wait. It's not nice to wait but it could wait and therefore we chose as a board - it was not just me - that... emergency care should take priority. He said he was ordered by the East Midlands Strategic Health Authority to meet the 18-week non-emergency target "whatever the demand" and was told to resign when he would not do so. He told the programme: "This is a culture of fear, a culture of oppression - of information that's either going to embarrass a civil servant or embarrass a minister. These are big problems. And if you consider that the people that have been running the NHS have created that culture of fear, they need either to be held to account or new people need to be brought in to change that culture. "I was in danger of losing my house - I have children to support," he went on. And one thing you must remember, that if you're attacking the very top of the NHS the sanctions are pretty dramatic. So I spent 20 years in the health service and I'm blacklisted from it. I can't work in the health service again. Today, we call again for Sir David Nicolson, at last, to accept that he has presided over a culture of fear and bullying in the NHS in recent years and that he acknowledges that this regime, which has damaged patient care, has been cruelly exposed. He should resign Rachael Maskell, head of health at union Unite He added: "You have to remember that if you work in the NHS and you cross the people in power there will be consequences for you and people are appointed to do specific jobs of getting rid of people. I think if you consider that had they got a case against me that was reasonable and it was gross misconduct, then why would they spend so much time, effort and money to silence me? Former health secretary Stephen Dorrell, who chairs the Commons health select committee, said the culture of gagging whistleblowers in the NHS was "corrupt." "This has been going on for far, far too long and I don't think your word corrupt is too strong," he told BBC Radio 4"s Today programme. It is fundamentally wrong that within a service that uses public money to treat patients, that information about patient safety should be regarded as something that is negotiable whether people are accountable for it. We need to deliver a fundamental change in a culture which thinks this kind of practice is acceptable. He said the committee would examine whether criminal sanctions were needed and would grill Sir David and Health Secretary Jeremy Hunt as part of an inquiry into the Francis Inquiry. But he played down the prospect of Mr Walker being called to give evidence. This has been going on for far, far too long Stephen Dorrell, former health secretary Mr Walker has urged MPs to help him expose further details, saying he could not say more "without incurring a much bigger risk of being sued by the NHS." I am still gagged,' he said. 'There's nearly 3,000 pages of evidence of which I have only been able to talk about a few. Those are the things I would like the health committee to expose. Mr Dorrell, who said the committee had been in correspondence with Mr Walker since his dismissal, insisted it was "not the function of Parliament to ... adjudicate different disputes that arise between the health service and its employees." We can't hear every case. The priority needs to be to ensure that action is taken that corrects that culture. As we made clear in our initial response to the Francis Inquiry last week, the culture in the NHS needs to change and high quality patient care must be paramount. 'Following Mr Walker's initial concerns raised in 2009 Sir David commissioned a rigorous independent review, following which it was concluded that no evidence whatsoever was found of bullying and harassment by the Trust or SHA.' A United Lincolnshire Hospitals NHS Trust spokesman told MailOnline: 'The agreement we reached with Gary Walker is not about stopping people from raising any concerns they may have around patient services, it related to his employment proceedings. The issue here is that a legal agreement on employment issues was negotiated by two parties, both of whom had access to legal advice. She added: 'A letter has been sent to Mr Walker by our solicitors, reiterating the terms of the agreement that was made.'