A Solihull mother-of-four endured an agonising death after she was wrongly given 10 times the normal concentration of a solution during a routine medical procedure, an inquest heard.

Rosemary McFarlane, aged 64, of Kingshurst Way, Kingshurst, was administered a lethal dose of phosphate buffer saline which caused her lungs to burn, by a consultant at Heartlands Hospital, who was unaware the concentration’s strength.

The inquest into Mrs McFarlane’s death was told how she suffered from an underlying lethal condition called cryptogenic fibrosing alveolitis, which causes scar tissue to replace normal lung tissue.

The grandmother-of-five was admitted to Heartlands on August 4, 2008, after months of feeling unwell and experiencing difficulty walking and climbing stairs.

On August 12, she underwent a routine bronchoscopy, where an instrument is passed through the mouth or nose into the lungs and fluid is squirted into a small part of the lung and then re-collected for examination.

Birmingham and Solihull Coroner Aidan Cotter heard how Dr Adel Mansur, who had 16 years experience of conducting bronchoscopies, was handed a bottle of phosphate buffer saline from a new batch with no additional information, by staff nurse Karen Richardson.

Dr Mansur told the inquest he was assumed the ‘10X’ written on the bottle was part of the long labelling code, was the same strength as other bottles he had always used for so many years and carried on with the 10 minute procedure.

When he injected Mrs McFarlane, the high dose caused water to move out of living cells leaving them damaged, dehydrated and causing adult respiratory distress syndrome, the inquest was told.

Nurse Richardson said she became greatly alarmed after the patient, who was expected to experience just mild discomfort after a bronchoscopy, started complaining of “severe burning” in her chest and other pains - something she had never seen in 14 years of practice.

Nurse Richardson said the batch was immediately withdrawn as Mrs McFarlane’s condition continued to deteriorate.

The patient was given steroids, oxygen and antibiotics, in the hope her condition would improve, as investigations were launched into how the solution had been supplied.

Mrs McFarlane’s family were informed the next day by Dr Mansur who became very emotional and went down on his knees to apologise.

Mrs McFarlane died on August 22, from multiple organ failure which had been caused by the chemical accident, pneumonia, a bacterial infection and other complications.

When asked by Mr Cotter why he didn’t check to see if he didn’t know what 10Xs meant, Dr Mansur said: “Because to me it was a pure replacement to a normal phosphate buffer solution, it didn’t alert me.”

Earlier in the inquest, pathologist Dr Adrian Warfield told how the wrong dose was so strong, it would have been enough to leave a fit, 30-year-old person, fighting for survival.

Dr Mark Goldman, the chief executive of Heart of England NHS Foundation Trust, has been summoned to give evidence at the inquest, which is expected to last until Wednesday.