Cooling prevents birth asphyxia brain damage
The MRC-funded TOBY trial (see feature) tested the theory that bringing about mild hypothermia in newborn babies with suspected birth asphyxia can reduce the brain damaging effects of oxygen deprivation. It followed 325 infants showing signs of birth asphyxia in hospitals in the UK, Ireland, Hungary, Sweden, Israel and Finland. The babies were randomly assigned to receive either cooling treatments (reducing body temperature to 33 to 34°C for 72 hours) or standard intensive care. Co-chief investigator Professor Denis Azzopardi, from Imperial College London and a member of the MRC Clinical Sciences Centre Neonatal Medicine Group, explains: "Although unfortunately it doesn’t work in every case, our study showed the proportion of babies that survived without signs of brain damage went from 28 per cent to 44 per cent with cooling treatments. This provides irrefutable evidence that cooling can reduce brain damage after birth asphyxia." The brain injury can go on for hours or days after oxygen deprivation first occurs, and this is the critical time when cooling is effective. Dr Azzopardi adds: "Lack of oxygen damages the mitochondria, the powerhouses inside cells. This sets off a chain of events which causes brain cells to go into apoptosis – programmed self-destruct mode. Cooling halts these processes, either by directly affecting apoptosis, stopping the chain reaction which begins it, or suppressing metabolism." The TOBY children will be invited to take part in the next phase of the study which will assess them at age six.
this provides irrefutable evidence that cooling can reduce brain damage after birth asphyxia