A SLOW injection of air caused the sudden collapse of a baby boy who was allegedly injured by a nurse, a court heard.
Lucy Letby33, is accused of try to kill the child in April 2016 while being treated at the Countess of Chester Hopital.
Expert witness Dr. Dewi Evans said he believes air “seeped” into the child’s bloodstream through a connecting port on his IV.
He told Manchester Crown Court it could have been “several minutes” before the child, Child M, deteriorated rapidly and nearly died as staff fought for nearly 30 minutes to resuscitate him.
Letby, is charged with attempted murder Child M on the afternoon of April 9, 2016 while being treated in nursery one at the Countess of the neonatal ward at Chester Hospital.
The defendant co-signed for an antibiotic administered through an IV port at 3:45pm – 15 minutes before Child M stopped breathing, followed by a dip in his heart rate and oxygen levels.


Letby was near the doorway of room one helping a colleague prepare medicine for Child M’s twin brother when the alarm went off at 4 p.m., the court heard Thursday.
Consultant Pediatrician Dr. Evans said using a syringe to inject air through a port would be slower than direct injection into the bloodstream.
Prosecutor Nick Johnson KC asked, “Would it follow that if someone chose to do it that way, they wouldn’t necessarily be standing over the baby at the time of the collapse?”
Dr. Evans replied, “Yes, because you wouldn’t necessarily collapse right away.
“It could have happened in minutes.”
Ben Myers KC, defending, said: “If there was enough air in his system to cause cardiac arrestthere won’t be such a quick recovery in 30 minutes.”
Dr. Evans said: “I disagree.
“The CPR was absolutely incredible.
“This was a very, very robust period of CPR that was needed.
“This is pretty consistent with a baby having air in the bloodstream, I can’t think of any other cause.
“The volume required is quite small. No nurse or doctor would allow an air bubble to enter the bloodstream.”
Dr. Evans said any air bubbles would dissipate when chest compressions were performed.
Mr. Myers told Dr. Evans that he had no empirical research to support his view that air can disappear in 30 minutes.
Dr. Evans said he relied on his knowledge of “basic anatomy and physiology”.
Mr. Myers continued, “You don’t actually know how much air it takes to cause a collapse?”
Dr. Evans replied, “No. ‘Very little’ is all I can say.”


Letby, originally from Hereforddenies the murder of seven infants and the attempted murder of ten others between June 2015 and June 2016.
The trial continues on Friday.