A LINE of gas in front of the spine was an “unusual finding” on the post-mortem X-ray of a baby allegedly murdered by nurse Lucy Letby, her trial has heard.

Paediatric radiologist Prof Owen Arthurs told Manchester Crown Court that its appearance was “consistent with, but not diagnostic, of air having been administered”.

Letby, 32, is said by the prosecution to have injected air into the bloodstream of the newborn twin, Child A, who later collapsed and died on the evening of June 8, 2015, just more than 24 hours after his premature birth.

Letby is on trial accused of the murders of seven babies and the attempted murders of 10 others at the Countess of Chester Hospital’s neo-natal unit.

Jurors were told that Prof Arthurs, professor of radiology at London’s Great Ormond Street Hospital, had been instructed to review X-rays taken of Child A – when alive and after death – as well as other babies in the investigation.

Looking at one of the post-mortem X-rays, he highlighted to the court there was gas within the bowel – a normal feature, he said – and also the heart.

Prosecutor Nick Johnson QC asked: “Anything unusual about the X-ray?”

Prof Arthurs replied: “You can also see a line of gas just in front of the spine. That is an unusual finding.”

He said such an image would not be seen in deaths by natural causes but had been documented in cases of road traffic accidents and sepsis infection.

He went on: “In my opinion this was an unusual appearance. In the absence of any other explanation this appearance is consistent with, but not diagnostic, of air having been administered.”

Prof Arthurs said he could not say from the image alone that an air embolism – a gas bubble which enters a blood vessel – was the cause of Child A’s death.

The court has heard previously that Child A did not have intravenous fluids for up to four hours on June 8 before he received glucose through a “long line” plastic tube at 8.05pm – shortly after the defendant came on duty.

Earlier on the shift, a cannula to a blood vessel stopped working, followed by two failed attempts to correctly insert a catheter in the belly button.

Prof Arthurs told the court it was “possible” that gas could have been introduced by one of those above devices.

Mr Johnson asked: “Have you ever seen this much gas in a baby that has not been explained?”

Prof Arthurs replied: “Only in one other case.”

Mr Johnson said: “One of the other children in this case?”

“That’s right,” replied the medic.

Prof Arthurs said he based his opinion on a published peer-reviewed study in 2015 which looked at how common it is that gas occurs in older children who have died, albeit with “very few babies” included in the study.

He went on to review the deaths of 500 infants at Great Ormond Street.

The radiologist also reviewed the X-rays of Child A’s twin sister, Child B, who the Crown say Letby attempted to murder via an injection of air on the following night shift at the neo-natal unit.

Prof Arthurs said he found “no significant abnormalities” on her radiographic images, including on a X-ray taken 40 minutes after Child B suffered a sudden collapse, which the Crown say Letby was responsible for.

Later on October 21, the court heard evidence from a woman who had been a neonatal unit nurse shift leader at the Countess of Chester Hospital on June 7.

She recalled she had "never seen a baby look that way before", with a skin discolouration on a pattern she had "never seen before".

Asked to describe the discolouration, she said he was "white with purple blotches", with a bit of "blue", and it had "come on very suddenly".

A court order prohibits reporting of the identities of surviving and dead children allegedly attacked by Letby, and also prohibits identifying parents or witnesses connected with the children.

Letby, originally from Hereford, denies all the offences said to have been committed between June 2015 and June 2016.