Why this case is anchor-load-bearing
In a multi-count indictment of a nurse accused of a pattern of killing, the first indicted death functions as the anchor. The Crown’s framing of every subsequent collapse and death — the pattern argument, the air-embolism framework, the shift chart — starts from the premise that the first death was deliberate. If that premise fails, the subsequent pattern argument loses its starting point.
Baby A is that first death. What the jury accepted about Baby A determined what they could accept about everything else. The International Expert Panel’s February 2025 summary report states a positive alternative cause of death for this case — not merely a doubt about the Crown’s theory.
The clinical record, as the Panel sets it out
The Panel records Baby A (its Baby 1) as a 31+2 week, 1.66 kg, male infant, the second of twins, delivered by emergency caesarean section for maternal hypertension. His mother had anti-phospholipid syndrome and gestational cholestasis — neither of which, the Panel notes, was charted in the medical records. At birth he required resuscitation but stabilised.
On the following day, the Panel records this sequence:
- At about 1600 hours, the peripheral intravenous line tissued and IV fluids were stopped.
- An umbilical venous catheter was inserted, but replaced for malposition.
- A long peripheral line was inserted at about 1900 hours.
- Fluids were reinfused at about 2000 hours.
- Soon after, he suddenly became pale, poorly perfused, apnoeic and desaturated. He was intubated, resuscitated, and given seven doses of adrenaline — but no blood gases were taken during the 30 minutes of resuscitation. His heart rate dropped and small ECG complexes were noted. Skin discolouration was observed: blotchy patches of brighter pink on a bluey-grey background. He did not respond, and treatment was withdrawn.
The prosecution theory
As the Panel summarises the conviction: it was alleged that Baby A died from injection of air into the intravenous line, causing air embolism resulting in collapse, patchy discolorations of the skin, and death. The Crown’s medical experts relied on the Lee & Tanswell 1989 paper when interpreting the skin signs. See our line-by-line comparison.
What the Panel actually concluded
The Panel’s conclusions on Baby 1 are two, and they are stated flatly:
- Baby 1 died from thrombosis.
- There was no evidence of air embolism.
The reasoning the Panel gives for those conclusions is as follows.
- Patchy skin discolouration is not a sign of air embolism. In December 2024, Zhou and Lee published new research showing that patchy skin discolouration has never been reported in infants with venous air embolism, including intravenous injection of air. When air is injected into the veins, the bubbles must first traverse the lungs, where they are filtered out by a vast bed of small blood vessels. In infants a hole in the heart (the foramen ovale) normally closes shortly after birth, so it is possible for bubbles to escape into the arterial system — but Zhou and Lee reported no patchy skin discolorations in infants given intravenous air. Patchy skin discolouration is caused by dilation and contraction of small blood vessels in the skin in response to hypoxia, which can occur in many conditions.
- The mother had anti-phospholipid syndrome. In this condition the immune system creates antibodies that attack the body’s own tissues and can trigger blood clots in arteries and veins. In pregnancy these antibodies can cross the placenta to the neonate and lead to thromboembolism, particularly where there is concurrent infection. The Panel notes this diagnosis was not charted in the medical records.
- Post-mortem showed a recent thrombotic event. The post-mortem of Baby A found a recent non-occluding thrombus in the liver — which means there had been a recent thrombotic event.
- Two central catheters were left without infusion for up to four hours. On the day of the collapse Baby A had two central catheters left without infusion for up to four hours, which predisposes to thrombosis. Shortly after infusion was started in the most central line, he collapsed. The Panel’s mechanism: a thrombus from the catheter tip likely migrated to an artery supplying the brain stem, causing sudden collapse and the inability to resuscitate him.
- A second thrombotic route is also possible. The Panel adds that Baby A may have had placental fetal vascular malperfusion, in which small thrombi in the fetal villi of the placenta travel to and occlude small blood vessels in major organs such as the heart, brain and liver. A small thrombus landing in the artery supplying a critical structure such as the brain stem can cause sudden death, and such thrombi are very hard to find at post-mortem. Collapse associated with fetal vascular malperfusion can occur one to two days after birth.
The impact on everything else
If the Panel’s reading is correct — that Baby A died of thrombosis, in an infant predisposed to it by maternal anti-phospholipid syndrome and by two central lines left unperfused — then the Crown’s anchor fails. Every subsequent count was presented in the context of a pattern that started on 8 June 2015. The pattern is only a pattern if each of its constituent events was deliberate. If Baby A’s death was thrombotic, the pattern argument does not begin.
The twin, and the shared maternal exposure
Baby A’s twin sister (Baby B) collapsed the following night and was resuscitated. The Panel reviewed her as Baby 2 and concluded that she too collapsed from thrombotic emboli originating from a central intravenous catheter, potentially aggravated by the same maternal anti-phospholipid syndrome, with no evidence to support air embolism. In the Panel’s account of Baby 2, Baby A’s post-mortem liver thrombus is cited as one of the reasons Baby B was at high risk of thrombosis herself. The two collapses share a maternal cause and a catheter-related mechanism. See our Baby B deep-dive and our twins and multiples deep-dive.
Sources
- International Expert Panel — Summary Report (February 2025), Panel Baby 1 (Trial child A).
- Zhou Q, Lee SK. Am J Perinatol, 27 December 2024. doi: 10.1055/a-2508-2733 — the paper the Panel cites for the finding that patchy skin discolouration has never been reported in infants with venous air embolism.