New animal research suggests that common practice in caring for premature infants might exacerbate a condition that can lead to permanent brain damage.
The article, entitled “Effects of Body Temperature Maintenance of Glucose, Insulin, and Corticosterone Responses to Acute Hypoxia in the Neonatal Rat,” is published in the American Journal of Physiology – Regulatory, Integrative, and Comparative Physiology.
Hershel Raff, PhD, professor of medicine at the Medical College of Wisconsin and director of the Endocrine Research Laboratory at Aurora St. Luke’s Medical Center, is the lead author of the study.
Premature infants’ immature lungs and frequent dips in blood pressure make them especially vulnerable to hypoxia, a condition in which their tissues do not receive enough oxygen, and can lead to permanent brain damage.
In this study, researchers found that rat pups exposed to low oxygen, but kept warm, had changes in insulin and glucose regulation that lead to hypoglycemia. However, when the rats were allowed to spontaneously cool, which is a natural response to decreased oxygen in the blood, they kept their glucose and insulin values more stable over time.
The findings suggest that cooling premature infants who have undergone oxygen deprivation, rather than placing them in incubators or under warmers, could help stave off brain damage associated with this condition.
Additionally, researchers suggest that keeping the animals warm may encourage swings in blood sugar that increase metabolic and physiologic demands and decrease the amount of glucose available to tissues. In rats, and perhaps in premature babies as well, this effect could lead to a variety of problems, including neurological damage. The authors note that, to their knowledge, there are no specific guidelines that address body temperature management for human premature babies with hypoxia.
“We hope that our studies in the neonatal rat will translate to appropriate studies and guidelines for the control of body temperature in the hypoxic newborn,” Dr. Raff said.
The other authors of the paper are Mitchell A. Guenther and Eric D. Bruder, of Aurora St. Luke’s Medical Center in Milwaukee.