A nurse looking after a four-year-old boy recovering from heart surgery on a controversial hospital ward admitted making mistakes in his care, an inquest has heard.
Diane Barlow, a cardiac nurse specialist, was caring for Sean Turner on the day he suffered a cardiac arrest on Ward 32 of Bristol Children's Hospital.
Sean, from Warminster, died in March 2012 from a brain haemorrhage, six weeks after he underwent vital corrective heart surgery at the hospital.
His parents, Steve, 47, and Yolanda, 45, say they begged doctors and nurses on the ward to help their desperately ill son.
They have both given harrowing accounts of Sean's care and treatment during the inquest at Avon Coroner's Court.
The inquest heard the little boy, who loved Spider-Man, suffered the cardiac arrest on February 16, having undergone the Fontan heart procedure on January 25.
Giving evidence, Mrs Barlow said she had made a mistake when changing Sean's chest drains and had not created an underwater seal but insisted she noticed it immediately and quickly rectified it - but had not made a note of it on Sean's records.
She said her mistake in the changing the fluid drains could have led to a nemothorax - a collection of air or gas in the chest that causes part or all of a lung to collapse - but a chest X-ray carried out that morning showed that had not happened in Sean's case.
"I think in the stress of the day I didn't put it down on the nursing notes," she told the hearing.
"I think I had alerted my nurse in charge, the outreach nurse and the medical staff.
"In my head I knew there had been an X-ray which showed no nemothorax.
"I should have recorded it and didn't."
Mrs Barlow told the inquest that her role as a cardiac nurse specialist also included non-clinical work and she worked one shift a month on Ward 32 caring for sick children.
She said that because of his parents' concerns and after observing his deterioration she asked for him to be examined by other nurses and doctors.
Mrs Barlow said Sean had a swollen leg, was pale in colour, had a restless night and had also vomited.
The hearing has heard that Sean suffered the cardiac arrest shortly after his femoral line, which was inserted in his groin, was removed by a nurse.
The boy's parents maintain that Mrs Barlow removed the femoral line on her own while Sean was being cradled in his father's arms.
Hospital protocols say the procedure should be carried out by two nurses while the patient is lying horizontal.
Giving evidence, Mrs Barlow rejected Mr and Mrs Turner's evidence and said she assisted as Sue Conner - the nurse in charge of the ward that day - removed Sean's femoral line, as he lay on the bed being comforted by his father.
Also present, she said, was outreach nurse John Daly, and Dr Guido Pieles, a cardiac registrar.
Adam Korn, the barrister representing the Turner family, asked whether Mrs Barlow could have been mistaken about Mr Turner cradling his son when the femoral line was removed.
"No, Sean was in bed," she insisted.
Mr Korn asked Mrs Barlow how it was that while she said Mr Daly, Mrs Conner and Dr Pieles were present when the femoral line was removed they did not make any reference to it in their statements to the court.
Mr Turner also maintains that Mrs Barlow removed the femoral line on her own.
"Is it possible that you are mistaken?" Mr Korn asked.
Mrs Barlow replied: "My recollection is that Sue Conner removed the femoral line and I assisted her and dad was comforting Sean and John Daly went to get a dressing from the dressing room."
Sue Conner, the nurse in charge on Ward 32, told the inquest she could not remember whether she was present when the femoral line was removed from Sean.
"If somebody says I was involved in the removal of the femoral line then I accept that," she said.
When Sean arrested she was not present but returned when she heard the emergency call.
Mrs Conner was asked specifically about Mr Turner's evidence in which he said she told him immediately after Sean's cardiac arrest "she had been worried about Sean".
"When Mr Turner said that yesterday I could not recall that," Mrs Conner said.
"On February 16 I was concerned about his deterioration over the few hours prior to his arrest."
Dr Pieles told the court he had ordered the removal of the femoral line but was not at Sean's bedside when it was taken out.
"I was not present during the whole of the procedure," he said.
"I did not have the time to spend in detail at Sean's bedside. My role was to delegate tasks and oversee tasks and to delegate. I would have not been present at the bedside."
Mr Korn asked Dr Pieles about Mr and Mrs Turner's view their son had been deteriorating for four days before he suffered the cardiac arrest and "nothing was done to help him".
Sean's parents have told the inquest how they begged doctors on Ward 32 for help and asked that he be transferred back to the intensive care unit.
"I can understand their concerns," Dr Pieles said. "But as a doctor working on that ward during that week we did all the best we could.
"When he came to the ward he was a stable patient and could be medically treated on the ward. It was a decision not made by one person but several cardiologists and the whole intensive care team."
Dr Pieles said Sean was an unwell child with a complex heart defect and had undergone major surgery.
He added: "I have gone through the medical notes and I have thought about his cardiac arrest and asked myself could it have been prevented?
"I think the medical care on the ward was appropriate."
Mr and Mrs Turner claim their son's death was not isolated and other children with heart problems have died at the hospital.
Up 10 families are believed to be taking legal action against the University Hospitals Bristol NHS Foundation Trust over treatment on Ward 32.
The inquest was adjourned until tomorrow