The death of a mum-of-two after surgery was the result of a complication so rare the surgeon had never seen it before, a hospital chief has said.
Louise Grant, of Ben Close, Loxley, died after surgery at the Northern General Hospital to remove a benign cyst believed to be on the outside of her lung.
After surgery, sutures used to tie off the pulmonary artery became dislodged and the 46-year-old bled to death internally.
Mrs Grant died at 3pm on July 29, 2011.
Dr David Throssell, medical director at Sheffield Teaching Hospital NHS Foundation Trust, said: “After considering all the evidence from a number of experts, the coroner concluded the tragic death of Mrs Grant was the result of an extremely rare complication which occurred once her surgery was complete.
“Indeed the complication was so rare that the surgeon had never seen it happen in his 17 years of thoracic surgery.
“Sadly if this complication occurs, even while the surgery is still taking place, the chances of survival are not high.
“Extensive resuscitation efforts were made to try to save Mrs Grant but sadly this was not possible.
“Of course no explanation of what happened will ease the loss felt by Mrs Grant’s family at this terrible time and to lose someone who was so dearly loved is devastating for everyone.
“Our thoughts are with Mrs Grant’s family and friends at this time.”
Legal action is to be taken against the hospital trust by Mrs Grant’s relatives after an inquest into her death.
The trust has denied liability.
The coroner recorded a narrative verdict at Mrs Grant’s inquest earlier this week.