What happened, according to the Panel’s summary of the record
Child K — “Baby 11” in the Panel’s report — was a 25-week, 692g female infant born by footling breech. At birth she was dusky and floppy, with a heart rate of 60 per minute and no spontaneous respiration. She was resuscitated with bagging and intubated after three attempts with a size 2 endotracheal (ET) tube. Blood-stained secretions were noted. She was mechanically ventilated, and a large air leak of 94% was recorded. Her blood gases showed respiratory and metabolic acidosis.
An hour and a half later she desaturated. A consultant bagged her with a Neopuff, but there was no chest movement, and the capnography test was negative for carbon dioxide. He re-intubated her with a size 2.5 ET tube, re-established chest movement and stabilised her. Her chest X-ray was consistent with respiratory distress syndrome or pneumonia. There were two further episodes of desaturation requiring resuscitation, and she was transferred to Alder Hey Hospital.
What the Crown alleged
The consultant alleged that Child K’s first episode of clinical deterioration was caused by deliberate dislodgement of her endotracheal tube. His reasoning rested on two observations: that bagging failed to move the chest, and that carbon dioxide was not detected by capnography. He also alleged that the incubator alarms had been deliberately turned off to prevent a prompt rescue response, because he did not hear the alarms when he entered the room.
The prosecution case at the retrial rested on Dr Ravi Jayaram’s eyewitness account of entering Child K’s bed space and finding Lucy Letby standing over the baby, with the tube dislodged, without calling for help. The inference invited from that account was that Letby had dislodged the tube herself and was waiting for the baby to collapse.
What the Panel found: an undersized tube and a 94% air leak
The Panel’s opinion is that Child K required a size 2.5 ET tube. Instead she was traumatically intubated with a size 2 tube, with a resulting 94% air leak. A leak of that size means that 94% of each delivered breath escaped around the outside of the tube rather than entering the lung; only 6% reached it.
The consequences, in the Panel’s account, follow mechanically. Ventilation was ineffective, because effective gas exchange could not occur on 6% of each breath. Mechanical ventilation could not generate sufficient pressure to hold the small air spaces in the lung open. That led to gradual collapse of those air spaces and progressively deteriorating gas exchange. When the tipping point was reached, the infant decompensated, desaturated and collapsed.
This is the Panel’s central finding, and it is not a claim that a dislodged tube would have been unremarkable. It is the stronger claim that no dislodgement is required to explain what happened, and that the record contains no evidence to support one. The tube that was actually in place — too small, leaking 94% — is sufficient on its own to account for the deterioration.
Why the Neopuff did not move the chest
The consultant treated the failure of bagging to move the chest as evidence that the tube was out of the airway. The Panel explains it differently. Bagging to reopen collapsed small air spaces in the lung requires relatively high pressures. The Neopuff has a safety feature that limits the air pressures it will deliver. With a 94% air leak, the Neopuff could not generate sufficient pressure to move the chest — not because the tube was displaced, but because the device is designed not to exceed its pressure limit, and almost all of what it delivered was escaping around an undersized tube.
Why capnography read negative
Capnography was the consultant’s second reason for inferring dislodgement: no carbon dioxide detected, therefore no tube in the trachea. The Panel notes that the device measures the build-up of carbon dioxide inside the endotracheal tube during expiration. With a 94% air leak, carbon dioxide could not build up in the tube sufficiently to trigger measurement. A negative reading was the expected result of the leak, not proof that the tube had come out.
The Panel’s conclusions on this point are blunt. It found that the initial intubation was traumatic and poorly supervised, and that the consultant did not understand the basics of resuscitation, air leak, mechanical ventilation, and how equipment that was in common use on the unit — the Neopuff and the capnograph — works. The two observations presented to the jury as signatures of sabotage are, on the Panel’s reading, the predictable behaviour of the equipment in the presence of a 94% leak.
The incubator alarms
The allegation that the alarms were deliberately silenced rests on the consultant’s statement that he did not hear them. The Panel records that a nurse — not Lucy Letby — stated: “When I returned to the unit, I immediately became aware of the alarms sounding from Baby 11’s incubator.” The Panel concluded that there is evidence the incubator alarms were not turned off.
The Panel’s conclusions on Child K
- There is no evidence to support a dislodged endotracheal tube.
- The clinical deterioration was caused by use of an undersized endotracheal tube.
- The initial intubation was traumatic and poorly supervised.
- The consultant did not understand the basics of resuscitation, air leak, mechanical ventilation, and how commonly used equipment such as the Neopuff and the capnograph work.
- There is evidence that the incubator alarms were not turned off.
Source: International Expert Panel — Summary Report (February 2025), “Baby 11”. Every medical statement on this page is drawn from that document.
What Dr Jayaram’s own contemporaneous notes show
Separately from the Panel’s medical review, independent commentators have noted a difference between what Dr Jayaram recorded in his contemporaneous 2016 notes and what he told the retrial jury in 2024. The specific detail that most supports the prosecution inference — the suggestion that Letby was standing passively over the baby without calling for help — is not present in the contemporaneous written record at the same level of emphasis.
This is not an accusation that Dr Jayaram has been dishonest. Memory of a traumatic event on a neonatal unit, reconstructed under oath eight years later, will not match a contemporaneous note perfectly. It is, however, an argument that the jury should have had the contemporaneous note and the 2024 oral testimony in front of it together, with the differences examined.
See our summaries at Dr Ravi Jayaram — witness evidence and day 2 of his Thirlwall evidence.
Why the retrial conviction is a specific CCRC question
The retrial conviction is procedurally separate from the original 2023 convictions. The CCRC application filed by Mark McDonald KC in October 2025 addresses both. The Child K conviction is, in many ways, the cleanest evidential test of the post-conviction expert evidence, because it rests on a single alleged act at a single moment rather than on a pattern aggregated across many babies.
On the Panel’s analysis, the medical foundation of that allegation does not hold. The two pieces of physical evidence offered for a dislodged tube — the chest that would not move and the capnograph that read negative — are what a 94% air leak through an undersized tube produces. If the Panel is right, there was no dislodgement to attribute to anyone, and the inference drawn from Dr Jayaram’s account has nothing left to attach to.