New Kiwi-led research looks set to prevent one of the most common causes of brain damage in babies.
The study has identified the safe threshold for a treatment given to infants born with hypoglycaemia or low blood sugar, a risk for almost thirty percent of all newborns.
The study, led by Professor Jane Harding and her team at Auckland's Liggins Institute, examined 404 babies who were born at risk of hypoglycaemia at Waikato Hospital and whose blood sugar levels were raised with either dextrose gel, dextrose injection or extra food, if needed.
That information has helped researchers identify the exact minimum blood sugar safety threshold doctors need to meet when treating these babies, which is 47 milligrams per decilitre.
"We know that a baby with a blood glucose level that is too low for too long will suffer neurological damage, but there has been debate about just how low, for how long, and in which babies," said Professor Harding.
"This is the first clear evidence that treating babies to keep their blood sugar above a widely-used safety intervention threshold does indeed protect them."
We know that a baby with a blood glucose level that is too low for too long will suffer neurological damage"
Professor Jane Harding
The study, part-funded by the Health Research Council, also identified that babies whose glucose levels rise too high or fluctuate widely in the first forty-eight hours of life are the ones most likely to end up with brain damage.
"It may be that it's not only important to keep blood glucose levels from dropping too low, but also to keep them from swinging too high, too fast, but we need further studies to confirm that link," says Professor Harding.
The babies were again tested at age two for cognitive and developmental progress to strengthen the findings.
Being born premature, or small or extra large at birth are the biggest risk factors for hypoglycaemia, along with the pregnant mother being diagnosed with gestational diabetes.