Mr Davies was transferred from the Royal Gwent Hospital

Graham Davies, 77, from Oakdale, near Blackwood, was given the wrong blood type after he was confused with another patient with the same name.

Relatives of the retired builder have said they were "devastated" after a coroner recorded a verdict of natural causes at an inquest last Friday.

The coroner concluded there was no proof that the transfusion of the wrong blood had caused Mr Davies' death.

Solicitor for the Davies family, Tunji Fahm, said he was seeking further advice on the case.

"Members of the family were very distressed and distraught at the verdict," he said.

They [the family] feel that they were let down by the system Tunji Fahm, solicitor

"In view of the fact that previously the chief executive of the Royal Gwent Hospital has issued a fulsome an unconditional apology to them as to the mix-up of the blood specimen, that [civil action] is actively under consideration.

"I have instructions to take further advice."

Mr Davies had been transferred from the Royal Gwent Hospital in Newport to the University Hospital of Wales in Cardiff after the main blood vessel to his heart ruptured.

The hearing in Cardiff was told that a mix up meant the wrong blood was sent with him.

Mr Davies, was a type O positive but he was given three units of A negative blood.

Laboratory technicians realised the error during checks and immediately contacted the surgeon during the emergency operation.

Mr Davies was given fresh blood, but died.

Vascular surgeon Dr Tudor Davies told the hearing the operation's survival rate was very low and Mr Davies only had a small chance of the operation being a success.

Investigation

The coroner, Dr Lawrence Addicott, said it could not be proved that the incorrect blood transfusion directly led to Mr Davies death.

"They [the family] are not seeking retribution they only want to establish what the facts are and to take advice as to what the best steps forward," said Mr Fahm.

"They feel that they were let down by the system."

A spokesperson for the Royal Gwent Hospital said there was a thorough investigation which had highlighted two areas of concern.

Protocols were immediately reviewed and amended where necessary and a rigorous training programme was introduced to raise awareness and prevent any recurrence.

The spokesperson added that Mr Davies' family has received a detailed explanation of what happened and the outcome of the inquiry.