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Blood urea nitrogen concentrations in low-birth-weight preterm infants during parenteral and enteral nutrition
Paola Roggero1, Maria Lorella Giannì, Laura Morlacchi
1NICU, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, University Department of Mother and Infant Sciences, University of Milan, Milan, Italy. roggero@unimi.it
Insights
Blood urea nitrogen (BUN) levels in preterm infants do not correlate with protein intake during early parenteral nutrition but can indicate adequate protein intake during enteral feeding. This finding helps optimize nutrition for premature babies.
Area of Science:
- Neonatology
- Pediatric Nutrition
- Biochemistry
Background:
- Early amino acid administration is recommended for preterm neonates to prevent protein catabolism.
- Blood urea nitrogen (BUN) is a potential indicator of protein intake and metabolism.
- Monitoring protein intake is crucial for the growth and development of preterm infants.
Purpose of the Study:
- To investigate the relationship between protein intake and BUN levels in preterm infants.
- To assess BUN as an indicator of protein intake throughout parenteral and enteral nutrition.
- To determine factors influencing BUN concentrations in preterm neonates.
Main Methods:
- Prospective, longitudinal, observational study of 92 preterm newborns.
- Blood urea nitrogen (BUN) levels measured at specific time points: days 2, 5, 15 of parenteral nutrition, at 160 mL/kg milk intake, and 36 weeks postmenstrual age.
- Protein intake calculated from 24-hour periods preceding BUN collection; statistical analyses included multiple regression and simple correlation.
Main Results:
- Gestational age negatively correlated with BUN during parenteral nutrition.
- Protein intake did not correlate with BUN on days 2, 5, and 15 of parenteral nutrition.
- A moderate positive correlation between BUN and protein intake was observed during enteral feeding (160 mL/kg milk intake and 36 weeks postmenstrual age).
Conclusions:
- High BUN in early postnatal period may result from factors other than amino acid intolerance.
- Blood urea nitrogen (BUN) can serve as a useful index for monitoring protein intake adequacy during enteral nutrition in preterm infants.
- Further research may refine BUN's role in assessing nutritional status in neonates.
Objectives:
Early amino acid administration has been recommended in preterm neonates to avoid protein catabolism. In the present work, blood urea nitrogen (BUN) was used to evaluate the quantity of protein intake in preterm infants. The aim of the study was to investigate the relation between protein intake and BUN during the entire duration of parenteral and enteral nutrition.
Patients And Methods:
We conducted a prospective, longitudinal, observational study. BUN was assessed in 92 preterm newborns on days 2, 5, and 15 of parenteral nutrition, on the day when infants consumed 160 mL/kg of milk, and at 36 weeks of postmenstrual infants' age. Protein intakes were calculated from the 24-hour period preceding the time the BUN specimens were collected. The effects of gestational age and protein intakes on BUN concentrations during parenteral nutrition were ascertained by multiple regression analyses. The relation between BUN and protein intakes during enteral feeding was evaluated by a simple correlation analysis.
Results:
Using linear regression analyses, gestational age showed a significant negative correlation with BUN concentrations during parenteral nutrition, whereas protein intakes at 2, 5, and 15 days did not correlate with BUN. A moderately positive correlation between BUN and protein intake was found when the infants consumed 160 mL/kg of milk and at 36 weeks of postmenstrual age (r = 0.5, P = 0.001 and r = 0.49, P = 0.012, respectively).
Conclusions:
In the early postnatal period, high BUN could be the effect of many factors other than amino acid intolerance. In contrast, BUN may represent a useful index in monitoring the adequacy of protein intake during enteral nutrition.
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