An international clinical trial has shown that a head-cooling device developed by New Zealand scientists reduces brain damage in oxygen-deprived newborn babies.
The findings, published in the prestigious medical journal The Lancet, offer new hope for preventing or reducing conditions such as cerebral palsy or severe intellectual impairment, according to the New Zealand scientists behind the research.
“Brain damage from oxygen deprivation is the single most important potentially treatable cause of childhood disability,” author Professor Peter Gluckman, director of The University of Auckland’s Liggins Institute, said in a statement. “The trial showed that in future there will be an effective treatment for many babies at risk of brain damage.”
To treat oxygen-deprived babies, Gluckman and Associate Professor Alistair Gunn at the Liggins Institute, and the late Associate Professor Tania Gunn, a neonatal specialist at National Women’s Hospital in Auckland, developed the Cool Cap, a cap that contains thermostatically controlled cool water circulated by a pump.
Oxygen-deprived babies treated with the Cool Cap in the international clinical trial showed a dramatic reduction in severe disabilities at 18 months of age compared with babies given standard clinical care.
According to Liggins Institute information, the time immediately before and after birth — called the perinatal period — is critical to a child’s development. About one or two in 1,000 newborn babies are at risk of brain damage during birth, despite what are often normal, healthy pregnancies. The result, if these babies survive, can be permanent intellectual disabilities or cerebral palsy.
Liggins Institute researchers have shown that many brain-injured babies appear to recover in the first few hours after birth. Then, however, the cells that initially survive remain at risk of swelling up and dying many hours afterwards. This phenomenon is called apoptosis, or “cell suicide”.
Head cooling can reduce that swelling and the death of brain cells that can occur in oxygen-deprived babies up to 72 hours after birth. The Cool Cap’s function is to lower the temperature of the baby’s brain during that critical 72-hour period, thereby protecting against apoptosis and allowing the body’s natural repair mechanisms to work.
The international clinical trial of the Cool Cap was carried out between July 1999 and January 2002, and involved 234 infants born at 36 weeks or older in 28 centers in the UK, USA, Canada and New Zealand. In the trial, the Cool Cap could not help the most severely affected babies. But among the other babies, the number who died was reduced from 39 per cent to 25 per cent. The incidence of handicap in the survivors was reduced by nearly two thirds, the Liggins Institute says.
The research began more than 20 years ago; the Lancet publication, completes, the Liggins Institute says, “a long journey of discovery.” Since the first informal release of the results of the clinical trial, two other groups have confirmed that the cooling approach is protective, which according to the Liggins Institute, shows that the Cool Cap trial has paved the way for treatment of a previously untreatable condition.
The first baby to have the cooling treatment at New Zealand’s National Women’s Hospital about 8 years ago has, according to the Liggins Institute, since done “very well”.