Parker Receives NIH Grants to Study Nutrition in Premature Infants
College of Nursing Clinical Assistant Professor and nursing researcher Leslie Parker, PhD, ARNP has received two National Institutes of Health grants to study nutritional outcomes and breastfeeding in the very low-birth weight infants.
A $1.4 million grant will determine nutrition outcomes and risks in the care of very low-birth weight infants, who weigh less than 3.3 pounds. The funding will allow researchers to study a clinical standard of care for assessing these infants’ nutritional status to determine if this standard is beneficial or risky to the baby.
Parker will lead a four-year study that will examine whether the customary clinical practice of assessing the amount of residual gastric contents in an infant’s stomach actually improves care or whether it can cause harm. Residual gastric contents are the volume of fluid remaining in the stomach after a feeding.
“Research has never evaluated whether this widely accepted clinical practice is beneficial to these very low-birth weight infants and whether it can actually cause real harm to infants,” Parker said. “It is our hope that the results of our study can have translational impact to evidence-based practice for patients.”
Very low-birth weight infants are too immature to coordinate sucking, swallowing and breathing, thus requiring the use of feedings through tubes inserted orally or through the nose traveling down the esophagus into the stomach. The customary clinical practice when tube-feeding is to determine if any breast milk or formula remains in the stomach by removing residual gastric contents through a tube into a syringe prior to each feeding. Future nutritional decisions are based on the volume or color of the fluid removed from the stomach.
Parker and her research team will study two groups of very low-birth weight infants in the neonatal intensive care unit at Shands at the University of Florida. One group will receive routine care. This includes assessment of residual gastric contents, monitoring for vomiting, measuring the size of the abdomen and assessing for bloody stools. The second group will not receive routine removal of residual gastric contents but will be assessed by the other routine methods of care.
Parker will evaluate the nutritional and gastrointestinal outcomes of both groups of infants to assess the risks and benefits of aspiration. All of the infants will receive breast milk from either their mothers or donors.
A second $400,000 National Institutes of Health grant will fund a study to assess the best time to initiate breast milk expression in mothers of very low-birth weight infants. Parker and her team, which includes CON Associate Professor Charlene Krueger and Clinical Assistant Professor Sandra Sullivan from the College of Medicine, will compare different times post-birth for expressing milk in the mothers and evaluate which time frame is optimal for ensuring adequate breast milk production.
It has been well-documented that breast milk is optimal for infants of all ages, and that is especially true for very low-birth weight infants. Breast milk provides vast protection to immature infants including improved digestion, decreased length of stay, and reduced risk of infection and necrotizing enterocolitis—a serious intestinal complication occurring in premature infants which vastly increases mortality and morbidity.
Unfortunately, mothers of very low birth weight infants often delay the initial milk expression session following delivery. Earlier initiation of milk expression has been associated with increased milk volume and an earlier lactogenesis stage II, which is the onset of copious milk production in mothers.
Parker’s pilot study found that women who started pumping within an hour of birth produced twice as much milk than others in the study, and 30 percent of women who waited six hours before initiation pumping produced no milk for the first three days after delivery.
“The literature has shown that most mothers of very low birth weight infants typically don’t initiate milk expression until 12 to 18 hours after birth,” Parker said. “With the results of our pilot study, we would like to see if an earlier milk expression can yield positive results with a larger sample size.”
Parker’s study will assess what is the optimal time for milk expression after birth, specifically comparing expression within one hour, one to three hours and six hours in a group of 180 randomly assigned mothers. The mothers will receive written and oral pumping instructions and will be visited approximately 24 hours after the initial pumping session to ensure they are using the pump successfully and provide additional instruction as needed. Upon discharge, mothers will be given a hospital-grade electrical pump.
The mothers’ milk volumes will be assessed at the initial pumping session, for the first 7 days and at five other days through 42 days after birth.
“I hope that my program of research can improve short- and long-term health outcomes for very low-birth weight infants by improving their nutritional status and decreasing complications due to prematurity.”