Marilyn Smith (74), first attended the emergency department at Hinchingbrooke Hospital on 8 September having injured her shin on a plant pot.
The wound was dressed but staff failed to ask Mrs Smith about her tetanus vaccination status.
Nine days later, Mrs Smith returned to Hinchingbrooke Hospital experiencing trismus, a spasm of the jaw muscles commonly known as lockjaw, which is a strong indicator of tetanus.
Mrs Smith was transferred to the emergency department at Peterborough City Hospital, where she was placed in a respiratory medical ward.
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Two days later, her condition deteriorated, at which point she was admitted to surgery for the insertion of a Vacuum Assisted Closure (VAC) dressing to her leg wound.
Between Mrs Smith being admitted shortly after the injury and her eventual surgery two weeks later, medical staff across the NWAFT potentially missed numerous opportunities to discover her tetanus immunisation status.
Knowing this sooner would have allowed medical staff to take appropriate action straight away.
The claims made in letters sent to Mrs Smith by “A group of staff at Hinchingbrooke Hospital” raise concerns surrounding the care which was “far below the standard expected” and claims there have been “serious concerns” raised in the past.
According to the letters, Mrs Smith missed out on the thorough cleaning of the wound with disinfectant and a tetanus injection she should have received.
Tetanus is rare in England because an effective vaccine forms part of the NHS childhood vaccination programme.
However, patients born before 1961 are far likelier to be unvaccinated.
NWAFT says that in response to shortcomings in Mrs Smith’s care, it has reminded all staff to ask about tetanus immunisation history and promised to include tetanus immunisation in staff training.
Speaking on behalf of Mrs Smith’s family, Tees Law solicitor, Tim Deeming, said: “While NWAFT’s internal report has acknowledged potential failings in Mrs Smith’s care, it is hard to believe that something as obvious and fundamental as tetanus was missed. We want to ensure that wider lessons are learnt across all clinical settings to improve patient safety in such situations.
“If the anonymous letters were written by staff at the hospital and the issues are credible, they are deeply concerning, especially given that they highlight concerns having been raised over the past five years. Reassurance is urgently needed from the Trust`s leadership about these potential allegations and any investigations undertaken.”
Caroline Walker, chief executive of North West Anglia NHS Foundation Trust, which runs Peterborough City, Hinchingbrooke and Stamford and Rutland Hospitals, was due to meet with Mrs Smith last week to discuss the report.
She said: “I would like to apologise to Marilyn Smith for the failure to identify her condition as quickly as we should have.
“Due to the rarity and severity of Mrs Smith’s condition, a clinical investigation took place to review the level of care experienced.
“We welcome the fact that our staff feel able to raise concerns. We have worked hard, with the support of our Freedom To Speak Up Guardian, to encourage an environment where speaking up is something people can do with confidence.
“When issues are raised we take action to investigate and learn from them.
“We are currently reviewing the details of this letter carefully to understand the nature of the allegations being made.”