Notice: You are viewing an unstyled version of this page. Are you using a very old browser? If so, please consider upgrading

TOBY Xenon: Neuroprotective effects of hypothermia combined with inhaled xenon following perinatal asphyxia

Principal investigators
David Edwards (Imperial College, London), Denis Azzopardi (Hammersmith Hospital, Imperial College, London)
Nicola Robertson (University College London), Mervyn Maze (Imperial College, London), Joseph Hajnal (Imperial College, London), Nicholas Franks (Imperial College, London), Ernest Cady (University College London), Ed Juszczak (NPEU)
Care of the compromised term infant
Medical Research Council
Start year
End year


Perinatal asphyxia severe enough to cause neonatal hypoxic-ischaemic encephalopathy (HIE) occurs in approximately 3/1,000 births in the UK, and over 1,000 moderate to severe cases of HIE are expected every year. The risk of death or severe handicap in survivors of moderate or severe HIE is approximately 25 and 75% respectively. Until recently no specific treatment for perinatal asphyxia was available, but trials of mild hypothermia have recently proved that in principle neuroprotective therapy after delivery is possible. However, the therapeutic benefit of hypothermia is modest and further neuroprotective interventions are urgently needed.

This was a proof-of-concept study to test if following perinatal asphyxia treatment with a combination of hypothermia and inhaled xenon reduces cerebral biochemical abnormality (assessed by Magnetic Resonance Spectroscopy), preserves cerebral structures (assessed by visual and computational analysis of MRI), and leads to improved clinical outcomes at hospital discharge, compared to standard care (therapeutic hypothermia treatment).


Journal Articles