Prevention of Neonatal Infection

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Dr. Richard Polin: "This is Richard Polin, I’m the Director of Neonatology at Columbia Presbyterian Medical Center and Professor of Pediatrics at the College of Physicians. I’m here right now in Salzburg, Austria at the end of a one-week course, which is a course on maternal and infant health. We’ve invited Dr. James McGregor to speak about obstetrical issues, Dr. Robert Clancy who is from the Children’s Hospital Philadelphia to speak about pediatric neurology, Steven Don from the University of Michigan speaking about pediatric cardiology, William Goldman from Wyeth Laboratories speaking about infant nutrition, and Richard Markowitz from the University of Pennsylvania speaking about pediatric radiology.

At this course there are sixty invited fellows from just about every country east of Vienna that used to belong to the Soviet Union. So we have people from the Ukraine, Russia, Mongolia, Croatia, and Albania - every former Soviet Republic. They get to spend a week here in Salzburg at the site where they hold the Salzburg Seminars, all their expenses are paid including meals and airfare. At the end of the course, they’re given a set of slides they can take back to their own country and the hope is that the information they learn here will be delivered to their friends and peers through lectures and informal conversation."

Dr. James McGregor: "This is Jamie McGregor, and I’d like to ask Dr. Richard Polin about new advances in terms of infection and inflammation during pregnancy and the problem of cerebral palsy which has so far resisted all of our attempts at doing better."

Dr. Richard Polin: "Yes, I certainly agree with your last statement that the incidence of cerebral palsy has not changed substantially despite many improvements in the quality of both obstetrical and neonatal intensive care. The greatest areas that I believe for improvement in the outcome of high-risk neonates will come from interventions aimed at in utero or intrauterine inflammation. And there’s mounting evidence, some of it fairly direct, much of it epidemiological studies demonstrating a relationship between chorioamnionitis and a later development of cerebral palsy both in premature and term-newborn infants. The other focus that I think we are learning to do better at is avoiding many of the complications of newborn intensive care such as intraventricular hemorrhage and paying closer attention to blood pressure and stabilization of vital signs. The final area which I think may have an impact on the outcome of cerebral palsy is the use of head cooling or hyperthermia in babies that have, unfortunately, been asphyxiated."

Dr. James McGregor: "What do you mean by head cooling?"

Dr. Richard Polin: "The notion is that there’s a critical period of time after an infant has been asphyxiated, no one’s quite sure of the exact time period, it’s probably up to about six hours. There is both animal data and now human data on about thirty newborn infants that cooling of the head and body - and we do this by using a plastic cap that fits over the skull through which cold water circulates - the baby’s body core temperature is reduced to 34 ½ degrees centigrade. The temperature of the brain is even cooler than that, probably a couple of degrees cooler. And the animal data says that if you cool the head of an animal that’s been asphyxiated, you can prevent the apoptotic injury, which occurs probably over a period of months after prenatal asphyxia. Even if head cooling is not a major intervention, the hope is that head cooling will prolong the critical time period for other kinds of interventions such as insulin-like growth factor which is now being talked about as a intervention for perinatal asphyxia."

Dr. James McGregor: "What about other suggestions of using agents which can scavenge oxygen radicals which are released during hypoxemia?"

Dr. Richard Polin: "If the mechanisms of brain injury are multiple and hypoxic, ischemic encephalopathy and include almost assuredly free radical injury, glutamate induced neurotoxicity, direct cytokine induced neurotoxicity, and finally apoptotic injury that occurs over a long period of time, and I think for us to be successful, we’re going to have to look at all the mechanisms involved in brain injury. Magnesium was a therapy that we hoped would have looked at the issue of glutamate neurotoxicity but in the studies done today, it doesn’t look like there’s a big enough signal that magnesium will be neuro protective."

Dr. James McGregor: "Would you speculate on which of these ways of possibly preventing cerebral palsy would actually be the most practicable in the near future? Would it be screen, treat, and prevent infections during pregnancy or would it be more rapid recognition of encephalopathy after birth?"

Dr. Richard Polin: "I would say the largest signal is going to be the screen, treat, and prevent infection in pregnancy. As few as 20% of cerebral palsy or as much as 35% may be due to infections which begin in utero. So in terms of the possibilities of preventing cerebral palsy, I think therapies aimed at identifying women with a potential for infection, and identifying that infection at the earliest time point is probably the therapy which is likely to achieve the greatest success."

Dr. James McGregor: "I would like to thank Dr. Richard Polin who is Chief of Neonatology at Columbia University School of Medicine. Thank you Rich."

Dr. Richard Polin: "Thank you."