A catalogue of errors and missed opportunities led up to the death of a grandmother left severely dehydrated at Maidstone Hospital.

Edna Thompson was rushed to the Hermitage Lane facility in September last year with a suspected malignant glaucoma in her right eye. She was prescribed mannitol, a powerful diuretic and died from an acute kidney injury just under a week later, despite family repeatedly warning she was becoming dehydrated.

Over the course of a bruising two-day inquest, the court heard that if doctors and nurses had stopped the medicine earlier the 85-year-old would still be alive.

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The coroner was told how not all doctors and nurses who cared for the Harrietsham mum-of-three were aware of the risks posed by mannitol, which rids the body of unneeded water and salt through urine.

It was prescribed by glaucoma fellow Dr Albrna Dardzhikova on an ongoing basis to Mrs Thompson to reduce the pressure in her eye. This was causing her intense pain and another medicine, diomox, had failed to work. Daily reviews were intended.

After a review a day later which Mrs Thompson was referred to Moorfields Eye Hospital, Dr Dardzhikova decided to continue the mannitol. She said she made this decision in conjunction with Mr Ejaz Ansari, a consultant ophthalmic physician.

But the coroner said there was no evidence from Mr Ansari as to whether he agreed to the continued mannitol use.

The coroner heard it is 'highly unusual' for the drug to be given on more than two occasions or 48 hours. Mrs Thompson received an infusion for five days before her sudden deterioration.

Dr Dardzhikova told the family on Monday: "I just want to apologise and express my condolences to the family and to say I am really sorry for your loss."

Dr Maria Dimitri, an ophthalmologist at Maidstone Hospital, saw the patient in an emergency eye clinic after she was admitted.

She told the court she did not implement daily reviews as she was unaware the former librarian was still taking the drug because her department kept separate records.

The coroner ruled this hampered nurses providing care and led to fluid balance until hours before Mrs Thompson's death and more missed opportunities to stop the drug earlier.

Giving a narrative verdict, senior coroner Patricia Harding said it was clear the use of mannitol was not reviewed and its diuretic effect not recognised until too late.

She said: "It is abundantly clear from the evidence that Mrs Thompson became dehydrated whilst under the care of the medical and ophthalmology teams such that she developed an acute kidney injury from which she died.

"I am further satisfied from the evidence of Dr Busch the medical consultant in charge of Mrs Thompson's care that on the balance of probabilities Mrs Thompson would not have died when she did but for the continued use of mannitol which caused her to become dehydrated."

She said she would not issue any recommendations as the hospital trust in question had made improvements.

Edna Thompson’s family have at last reached the end of their quest to find out why their mother died.

But it has been a long process made more difficult by that fact the coroner’s court investigation was plagued with problems and an inquest was only opened nine months after the death.

In June senior coroner Patricia Harding apologised, blaming “unprecedented pressures” on the court system and staffing issues.

Now they finally have an outcome, Mrs Thompson’s daughters said they are as shocked as they are relieved it is finally over.

Daughter Sue Ealding, said: "It is what we expected I think but at least it has proved the hospital were at fault and things needed to be put right.

"The best thing is the hospital have said that everything is being put into place to make sure it won't happen to anyone else. As long as they stay true to their word that's good enough for us."

Mrs Ealding's sister Ann Brown, added: "I hope they learn something from this and it isn't a waste of everybody's time and our mother's life."

Maidstone and Tunbridge Wells NHS Trust’s own investigation found a catalogue of errors in failing to prevent and act on the mother-of-three’s dehydration, including that she was given drugs known to cause thirst longer than she should have been.

A frank letter to the family admitted grave errors had been made.

Today, a spokesman apologised, saying: “Whilst nothing we can say or do can change the outcome, we have thoroughly investigated the care and treatment she received. As a result, we have implemented a number of improvements to our systems and processes to improve patient care.”