A woman has been awarded £11million in compensation after a routine operation on her ankle left her brain damaged.
The patient, who has asked to use the false name Deborah, now needs 24-hour care at home after a blunder with the anaesthetic.
The mistake by doctors at NHS' North Middlesex Hospital in Edmonton, north London, caused oxygen supply to her brain to be cut off during the procedure and she went into cardiac arrest.
Her motor and cognitive impairments have severely affected her memory, mental speed and other functions. She has also developed complex psychiatric symptoms.
But the NHS trust has now admitted liability.
Olive Lewin, of lawyers Leigh Day, said: "This was a particularly devastating case of negligence.
"My client went into the hospital a fit and healthy woman for a relatively simple operation.
"Due to failings in her care her life has been completely changed and she now requires 24-hour care.
"Not only is she not able do a job or to take part in the sports she loves, but she cannot live independently.
"I am pleased we managed to secure compensation which will help provide for her care needs going forward."
It was deemed that, on the balance of probabilities, Deborah's cardiac arrest would have been avoided if medics had observed her more directly and closely and detected her respiratory problems sooner.
Due to her injuries, the woman has had to quit the job she loved and stop sporting pursuits.
She has difficulty with fine finger movements, problems with balance and has weakness in both hands.
She also tires easily, and has lost her sense of taste and chokes on liquids.
She has developed a condition that causes involuntary muscle jerks called myoclonus.
The legal case was told Deborah was administered a drug called Doxapram when she was slow to wake at the end of the operation.
The respiratory stimulant though is only effective for a short amount of time.
It can therefore wear off before the effects of the drug it is being used to reverse.
It leaves the patient at risk of significant breathing problems caused by the paralysis of breathing during the operation.
And in Deborah's case, it was deemed the anaesthetist ought to have been aware of this danger.
They also should have instructed the recovery room nurse both of the fact that Doxopram had been given and that there was a need for particularly close monitoring of Deborah's breathing, particularly for signs that the effect of the drug may be wearing off before she was able to breath spontaneously.
It is believed that either this instruction was not given or, if it was given, it was not heeded.
After the operation, Deborah was transferred to the recovery room and the anaesthetist left her in the care of the recovery nurse but the emergency bell rang 15 minutes later.
North Middlesex Hospital accepted responsibility at the earliest opportunity.
