During gestation, an unborn child’s brain is vulnerable to a wide range of threats, including placental or umbilical problems, severe illness with the mother, or a difficult delivery. When a newborn is asphyxiated before or during birth, the ensuing lack of oxygen to the brain can result in a condition termed hypoxic-ischemic encephalopathy, or HIE.
The HIE condition evolves over several hours. The initial oxygen and/or lack of blood supply to the brain kicks off a series of other events as the body tries to repair itself. This natural approach is effective when HIE is mild. But in moderate or severe cases, the body’s desperate attempts to repair itself could cause more brain damage.
This damage does not occur immediately. It is the result of a cascade of chemical reactions, and there is a window of several hours before it becomes permanent. Therefore, researchers theorized that maybe it was possible to block the chemical chain reaction and minimize permanent damage. Up until the past couple of decades no intervention seemed to make much difference.
However, now a new and simple technique is giving brain-damaged babies a chance at a normal, healthy life. Recent research suggests that babies who are starved of oxygen at birth have a much lower risk of brain damage if they are given mild hypothermia, a cooling of the body temperature. This is achieved in one of two ways: through a special water-cooled cap or a fluid-filled blanket. Both methods are designed to reduce brain temperature. It has been found that reducing the temperature by 3-4○C for 72 hours after birth seems to switch off many of the damaging reactions. It is believed that cooling slows down chemical reactions, and gives the repair mechanisms inside cells a chance to work.
Brain hypothermia, induced by cooling a baby to around 33○C for three days after birth, has recently been proven to be the only medical intervention that reduces brain damage and improves an infant’s chance of normal survival after birth asphyxia. Brain cooling has become widely used in neonatal units throughout the United States.
Timing is critical. Brain cooling must be initiated within six hours of delivery. After the baby is born, doctors make some quick decisions to determine if he or she is a candidate for brain cooling. The newborn must have sustained moderate brain damage, be full-term or late pre-term (beyond 36 weeks), and be younger than six hours old. International studies report about a 27% decline in deaths and disabilities with brain cooling.
If your child has a brain injury or cerebral palsy, he or she possibly could have been offered brain cooling as a treatment.