RWJF Scholar Recognized for Research to Protect Preemies from Hypothermia
Robin Knobel, PhD, RN, is an associate professor at the Duke University School of Nursing and a Robert Wood Johnson Foundation (RWJF) Nurse Faculty Scholar (2010-2013). The University of Carolina at Chapel Hill (UNC-CH) School of Nursing recently recognized her with its Distinguished Alumna award.
Human Capital Blog: Congratulations on the award! What does it mean for you and for your research?
Robin Knobel: I was truly honored to receive this award from UNC-CH because it recognizes my achievement thus far in my career in my area of research around improving thermal stability with premature infants. I was given great support as a doctoral student at UNC-CH through mentorship in research from faculty who are leaders as nurse scientists. To be recognized by alumni and faculty of the UNC-CH School of Nursing is a tremendous honor.
HCB: You received the award for your research into physiologic processes related to thermoregulation and perfusion in extremely premature infants. Can you explain what this means in lay terms?
Knobel: Yes. Premature infants are born too early to be able to keep themselves warm through the normal methods of heat production. Normally, infants up to one year of age do this through a metabolic production of heat, instead of shivering. Premature infants lack necessary components to accomplish efficient production of heat and consequently can become very cold if exposed to cold air after birth and through stabilization in the neonatal unit. They often experience hypothermic body temperatures during the early weeks after birth, which can lead to instability and possible lasting insults such as brain hemorrhage, infection, or even death. My research is studying the mechanisms around thermal stability in premature infants and ways to prevent bad outcomes from hypothermia.
HCB: You were a neonatal nurse, and then a neonatal nurse practitioner, for more than two decades. What led you to move into scientific research?
Knobel: I last practiced as a neonatal nurse practitioner and often had to deal with infants who were unstable due to hypothermic body temperatures. I recognized how often this occurred and wanted to try to do something to protect infants from hypothermia. I did a study to reduce hypothermia in premature infants after birth using a type of plastic bag. We placed half the infants in these medical grade plastic bags right after birth, to prevent heat loss from their body, and then removed the bag after they were safely placed on a warming table in the neonatal intensive care unit (NICU).
Infants in the bags were much warmer than infants who were not placed in bags, and this intervention was eventually incorporated into the national standard of care for delivery room resuscitation. Conducting this study helped me realize the importance of research to improve care and also made me realize I needed further education to be able to conduct rigorous scientific research. I enrolled in doctoral education the year after completing this study.
HCB: Why did you decide to focus on premature infant body temperature regulation? Is that a common problem in the NICU, and what health risks are associated with it?
Knobel: It is a common problem, still today. Infants arrive from the delivery room cold and even if they come in warm through the use of the plastic bags, once the bag is removed and stabilization procedures are done, they continue to lose heat due to exposure of environmental air. Because they cannot generate their own heat sufficiently, we must protect them from heat loss through heaters, blankets, and protected environments. This poses an ongoing challenge. Hypothermia can lead to a greater risk of death, impaired blood glucose, a greater need for oxygen, and a strain on the cardiovascular and neurological systems, which increases the incidence of illness and instability.
HCB: In your work as an RWJF Nurse Faculty Scholar (NFS), you were trying to find ways to correct for abnormal blood flow among premature infants. What did you find?
Knobel: I examined central and peripheral body temperatures in premature infants over their first two weeks of life to try and understand why I had previously seen infants keeping their feet warmer than their abdomen for many hours of their first day. In my NFS study, I found infants earlier than 29 weeks gestational age were not able to regulate their body temperature through blood flow. Normally, if a person becomes cold in their central core body, they should constrict the vessels in their feet and hands to send blood to warm their core so they can protect central body organs such as the brain, the heart, and the gastrointestinal system.
The reason I’m interested in this mechanism is that about 7 to15 percent of extremely premature infants get a disease called necrotizing enterocolitis (NEC), which is a devastating disease of the gastrointestinal (GI) system. It has an incidence of death in up to 50 percent of infants who get it. If an infant cannot keep his or her central core warm through blood flow, this may explain one pathway to getting NEC. Researchers have been trying to identify the causes of NEC for more than 30 years without much success, but we do know that decreased blood flow to the GI tract is a contributing factor.
I feel that central hypothermia contributes to this problem. In my NFS study, infants continued to have warmer abdominal temperatures than feet temperatures for many time periods throughout their two weeks, which seemed to represent periods of instability. This is important because it will allow us to focus on those time periods with future research.
HCB: Would this research have been possible without your NFS grant?
Knobel: This research would not have been possible without funding from my NFS grant because it was a very complicated study that consumed a good amount of my time over the course of three years. The NFS funded a research coordinator for the study, Becky Jones, RN, BSN, from Duke University Medical Center. She devoted half of her time to making sure the procedures and measures of the study were rigorous. We successfully enrolled 30 infants in the study and have many outcomes to further explore.
HCB: What are your next steps in this area of research?
Knobel: We are designing a study to look at central and peripheral temperature in 500 infants in three different NICUs in relationship to outcomes such as NEC, brain hemorrhage, and death. This will allow us to make definitive conclusions about the importance of monitoring central and peripheral temperature continuously in premature infants, instead of following the current standard of care in monitoring only one temperature on the abdomen or under the arm.
HCB: Your work has led to changes in national guidelines regarding neonatal resuscitation. Can you describe these changes, and what impact do you think they’ll have?
Knobel: As I mentioned above, it is now a national standard for delivery room resuscitation, specified by the American Academy of Pediatrics, to place all infants younger than 28 weeks gestational age in plastic wrap or bags right after birth (without drying the infant) to prevent heat loss. My previous study in 2000 and studies done by colleagues were instrumental in providing evidence for this change. This intervention is now being adopted by low resource countries to help prevent hypothermia in larger infants as well.