Cooling down the bodies of babies who suffer a lack of oxygen at birth may save their brains, according to new research from the U.K.
When babies lack oxygen at birth, it can lead to cerebral palsy, brain damage, or even death. Now, researchers have found that forcing a four-degree Celsius drop in a baby's body temperature for 72 hours after a difficult birth can improve the baby's outcome.
The study, published in the New England Journal of Medicine, showed a 57 per cent reduction in the risk of brain damage when babies were given the cooling therapy compared with standard treatment.
Doctors are not exactly sure why body cooling helps, but think that slowing the babies' metabolism reduces the shock of the birth trauma, giving the brain's neurons that have been injured irreparably a chance to recover.
The study recruited 325 newborn babies who were suffering from oxygen deprivation from hospitals across Britain over four years. Outward symptoms included being unable to breathe unaided, a slow heartbeat, low blood pressure, and abnormal neurological signs.
Half the group received intensive care with cooling and the other half were given standard intensive care, which meant keeping the babies in incubators and maintaining their body temperatures at 37C.
The babies in the cooled group were wrapped up in a specially designed blanket with circulating cold fluid so that their body temperature was lowered to 34-35C. After 72 hours of cooling, the babies were slowly warmed back to a normal body temperature.
In the standard care group, 42 of the infants were found to have severe disabilities 18 months later, compared with only 32 of the infants who had received the cooling treatment. Death rates were not significantly different between the groups.
The co-chief investigator, Dr. Denis Azzopardi, from Imperial College London, believes the proof is "irrefutable" that cooling reduces brain damage in newborns.
"The study builds on a 20-year body of research but gives, for the first time, irrefutable proof that cooling can be effective in reducing brain damage after birth asphyxia," he said.
The researchers estimate brain damage caused by lack of oxygen at birth could be avoided for over 100 babies a year in the U.K. if infants were given cooling treatment within the first six hours of life.
Dr. Marianne Thoresen, who worked on this study and was among the first to show that mild cooling reduces injury in newborns after hypoxia, is now planning to research the effect of treating affected newborns with inhaled xenon gas as well as hypothermia, to see if that will give added brain protection.
