Whistleblowers at one of England's worst performing hospital trusts have said a climate of fear among staff is putting patients at risk.
Former and current clinicians at University Hospitals Birmingham (UHB) NHS Trust allege they were punished by management for raising safety concerns, a BBC Newsnight investigation found.
One insider said the trust was "a bit like the mafia".
The trust said it took "patient safety very seriously". It said it had a "high reporting culture of incidents" to ensure accountability and learning.
Staff concerns included a dangerous shortage of nurses and a lack of communication leading to some haematology patients dying without receiving treatment.
The deaths of 20 patients in the haematology department of the Queen Elizabeth Hospital, which is run by the trust, led to a review in 2017 by consultant Emmanouil Nikolousis.
Mr Nikolousis, who left the trust in 2020, told the BBC he was shocked by the failings he found and believes patients' lives could have been saved.
A report by Mr Nikolousis criticised a lack of "ownership" of patients and a lack of communication among senior clinicians. In some cases this led to patients dying without having received treatment, he said.
"Certainly there should have been different actions done," he said. "They could be saved. Certainly, when you don't have an action done, then you don't really know the outcome."
Mr Nikolousis said he felt he had no option but to quit after his findings were ignored and his position was made "untenable". He left the NHS after 18 years.
"They were trying, as they did with other colleagues, to completely sort of ruin your career," he said.
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Source: BBC News, 1 December 2022