The record of emergency drugs provided to the youngster was written on a paper towel by nurses involved in his successful resuscitation at the Countess of Chester Hospital’s neo-natal unit.
Letby, 33, gave rescue breaths to the infant after she responded to his cot monitor alarm on the afternoon of April 9, 2016, Manchester Crown Court was told on Tuesday, February 21.
The infant, known as Child M, suddenly collapsed in room 1 of the unit at 4pm as he stopped breathing and his heart rate and blood oxygen levels dipped.
Chest compressions commenced when he failed to respond, and six doses of adrenaline were required before his heart rate eventually rose to safe levels about 30 minutes later.
Giving evidence on Tuesday, nurse Mary Griffith said she was responsible for drawing up and checking the resuscitation drugs for Child M.
She told the court the paper towel would have been on the resuscitation trolley and provided a record for doctors of what drugs had been given and when as events unfolded.
Mrs Griffith said she recognised two of the entries for adrenaline administration were in her handwriting.
Simon Driver, prosecuting, told the court the paper towel – along with a blood gas measurement report for Child M – was discovered in a Morrisons shopping bag beneath a bed in a bedroom at the defendant’s former address in Westbourne Road, Chester, on July 4 2018.
Mr Driver asked Mrs Griffith: “Have you ever taken a blood gas record home with you?”
Mrs Griffith said: “No.”
Mr Driver went on: “Have you ever taken home with you the contemporaneous notes for medications given during a resuscitation?”
“No,” repeated the witness.
Ben Myers KC, defending, suggested to Mrs Griffith that some of the notes on the paper towel were also written by Letby.
Mrs Griffith replied: “I can’t say. I’m not going to guess.”
Mr Myers made the same suggestion to another nurse, who cannot be identified for legal reasons, who said she thought “possibly” one of the entries was in Letby’s handwriting, but added: “I can’t be sure.”
Letby, originally from Hereford, denies attempting to murder Child M and his twin brother, Child L, who she is alleged to have poisoned with insulin during the same day shift.
She denies the murders of seven babies and the attempted murders of 10 others between June 2015 and June 2016.
The trial continues on Wednesday, February 22.