A baby girl allegedly harmed by nurse Lucy Letby suffered two unexplained seizures within 30 minutes, a court has heard.
It is alleged the 33-year-old was on shift in the neonatal unit at the Countess of Chester Hospital when the premature baby's blood oxygen levels dropped unexpectedly.
While giving evidence on Monday 13 February, consultant paediatrician Dr John Gibbs, said two “profound” desaturations were “alarmingly low” at around 5am on 27 November 2015.
Manchester Crown Court heard that Child J, remained stable for weeks after undergoing bowel surgery the day after she was born.
Child J recovered rapidly after she received breathing support, but more desaturations followed at 6.56 am, together with a marked fall in heart rate.
Dr Gibbs also noted all of Child J’s limbs were “stiffly extended with her hands clenched” and that her stiffness took 10 minutes to settle which was a “reasonably long seizure”.
Child J was given additional breathing support with a face mask which led to an improvement.
However, jurors were told how a further similar episode took place at 7.24am.
Dr Gibbs, who is now retired, said: “Again, (Child J’s) oxygen and heart rate dropped and she needed support for her breathing just as in the first episode.
"This episode was much shorter. She did display the stiffness of all her limbs and clenches of her hands, and on the second episode her eyes deviated to the left.
"It stopped after three or four minutes.”
Dr Gibbs said that Child J had not suffered a seizure before or since. He also said that Child J had not suffered a seizure either before or since.
Simon Driver, prosecuting, said: “You cannot be certain as to what was the cause?”
Dr Gibbs responded: “All the investigations did not reveal any causes for her seizures.”
Ben Myers KC, defending, said: “It’s not possible to say for sure whether the seizures caused breathing difficulties or breathing difficulties caused the seizures?”
Dr Gibbs said: “That’s correct.”
Mr Myers continued: “To be clear, you favour breathing difficulties first because your assessment was the drop in oxygen [levels] came before seizure?
Dr Gibbs said: “Yes. Exactly why and how the oxygen dropped, I don’t know.”
Speaking in court Dr Stephen Brearey, fellow consultant, said Child J normalised "very quickly" during the day and "all the investigations we had undertaken couldn’t identify why she had the desaturations or explain why she had a seizure.“
He continued: "I do know hypoxia causes seizures so that would be possibly the most likely cause.
"There remains the question why was (Child J) hypoxic when two or three weeks beforehand she had been breathing normally in air and there was no suggestion of infection.
Dr Breary said they had stopped giving her antibiotics three days after starting them because "there was no evidence of infection in the blood tests and she remained well for weeks afterwards.”
Earlier, nurse Mary Griffith – who worked more than 40 years at the Countess of Chester before retiring in 2016 – agreed with Mr Myers that Letby was “knowledgeable”, “caring” and “thorough” in her job.
She also agreed there seemed to a “very high admission rate” to the neo-natal unit between 2015 and 2016.
Child J was discharged home in January 2016 and was described as progressing “very well” at her final outpatient clinic more than a year later.
Letby, originally from Hereford, denies murdering seven babies and attempting to murder 10 others between June 2015 and June 2016.
The trial continues.