Even with the healthiest of pregnancies, the birth of a child comes with risk. Major challenges for a full-term baby include the umbilical cord getting wrapped around the child’s neck or the placenta detaching prematurely before the baby is born.
When these incidents occur at birth, newborns may suffer from a severe lack of oxygen and blood flow to the brain, a condition called hypoxic ischemic encephalopathy (HIE). Children born with HIE have a high risk of dying or developing severe neurological and developmental handicaps. HIE affects 1 of every 1,000 newborns.
“It’s hard to be born,” said Associate Director of Neonatology at Cook Children’s Jonathan Nedrelow, M.D. “Some of these babies are starved of oxygen and blood flow for a period of time surrounding their birth.”
Only recently have Neonatal Intensive Care Units been involved in an innovative treatment called whole-body hypothermia. Physicians lower the body temperature of the babies by placing them on a cooling blanket made of soft plastic filled with circulating water, monitoring them with a thermometer placed inside their esophagus and attached to a computer system. After 72 hours, the babies are slowly rewarmed to a normal body temperature. Studies have shown this treatment reduces the risk of death or disability in infants with moderate or severe HIE.
Dr. Nedrelow likened it to children who fall through ice and into freezing water. This slows down their metabolism and in many cases, these children come out unharmed.
Dr. Nedrelow, who joined Cook Children’s four years ago, trained at the Yale School of Medicine. While at Yale, Dr. Nedrelow participated in a multicenter study looking at the effectiveness of whole-body hypothermia treatment for babies who had lost oxygen to the brain (known as asphyxia).
The study, published in the New England Journal of Medicine, found that infants born with severe oxygen loss to the brain have a greater chance of survival if their body temperature is lowered 4 degrees Fahrenheit for 72 hours. The rate of mortality among these infants decreased from 62 percent to 44 percent when they received the cooling treatment within six hours after birth.
Cook Children’s has treated 21 babies using whole-body hypothermia therapy since October 2006. Dr. Nedrelow uses a protocol from the original study that is followed at Cook Children’s as well as at referral centers throughout the state.
After an acute, or severe, event such as an umbilical cord wrapped around the baby’s neck, the pediatrician uses an information card created by Dr. Nedrelow to check the infant’s status. If the newborn meets certain criteria, the doctor immediately calls the Cook Children’s Transport team. Once the infant arrives at Cook Children’s, the Neonatal Intensive Care Unit physician on staff again follows certain steps, and if the baby meets the criteria, begins hypothermia therapy. Doctors have a six-hour window to start the treatment.
“There’s no way to entirely mitigate the risk of childbirth,” said Dr. Nedrelow. “A lot of pregnancies can be totally normal until the time of birth. Term babies have a reserve that others do not. Most of what makes babies better is their own restorative capacity, and we nudge them in the right direction.”