Supplemental protein and postnatal growth of very low birth weight infants: a randomized trial

Abstract

Background: Providing adequate nutritional support to promote optimal postnatal growth for very low birth weight (VLBW) infants has been a difficult problem to surmount in the NICU. During the past 4 decades, improvements in neonatal critical care have made it possible for more VLBW infants to survive to discharge from NICUs. The NICHD Neonatal Network reported that while intrauterine growth restriction was present in 22% of VLBW infants at birth, 91% demonstrated postnatal growth restriction by 36 weeks post menstrual age. The persistence of this nearly universal growth deficit is associated with the inadequacy of protein and energy intake, which may account for 45-50% of the postnatal growth restriction.

Objective: The purpose of this study was to assess whether increasing enteral intake, using supplemental protein, would improve postnatal growth for VLBW infants.

Study design: Randomized clinical trial. Sixty-four infants were enrolled (34 in control group with 15 infants <1000 g, and 30 in intervention group with 13 infants <1000 g).

Result: There were no sustained statistical differences between weekly measurements of weight, length, head circumference, and skinfold thickness between groups. There were no significant differences between laboratory results except blood urea nitrogen at time of peak protein intake for intervention group.

Conclusions: Supplemental enteral protein had minimal to no effect on postnatal weight, length, head circumference, body mass, or length of stay. It may be most important to provide consistent sustained nutritional support with protein from birth to reduce postnatal growth restriction, especially for those infants <1000 g at birth.

Keywords: Extremely premature infants; VLBW; growth restriction; human milk; nutritional requirements.