Resting energy expenditure in infants with congenital diaphragmatic hernia without respiratory support at time of neonatal hospital discharge.

BACKGROUND: Infants with congenital diaphragmatic hernia (CDH) are at risk for growth failure because of inadequate caloric intake and high catabolic stress. There is limited data on resting energy expenditure (REE) in infants with CDH. AIMS: To assess REE via indirect calorimetry (IC) in term infants with CDH who are no longer on respiratory support and nearing hospital discharge with advancing post-conceptional age and to assess measured-to-predicted REE using predictive equations. METHODS: A prospective cohort study of term infants with CDH who were no longer on respiratory support and nearing hospital discharge was conducted to assess REE via IC and caloric intake. Baseline characteristics and hospital course data were collected. Three day average caloric intake around time of IC testing was calculated. Change in REE with advancing post-conceptional age and advancing post-natal age was assessed. The average measured-to-predicted REE was calculated for the cohort using predictive equations [22]. RESULTS: Eighteen infants with CDH underwent IC. REE in infants with CDH increased with advancing postconceptional age (r2 = 0.3, p < 0.02). The mean REE for the entire group was 53.2 +/- 10.9 kcal/kg/day while the mean caloric intake was 101.2 +/- 17.4 kcal/kg/day. The mean measured-to-predicted ratio for the cohort was in the normal metabolic range (1.10 +/- 0.17) with 50% of infants considered hypermetabolic and 11% of infants considered hypo-metabolic. CONCLUSIONS: Infant survivors of CDH repair who are without respiratory support at time of neonatal hospital discharge have REE, as measured by indirect calorimetry, that increases with advancing post-conceptional age and that is within the normal metabolic range when compared to predictive equations. LEVEL OF EVIDENCE: III.

Comparison of Feeding Strategies for Infants With Hypoplastic Left Heart Syndrome: A Randomized Controlled Trial.

INTRODUCTION: Infants with hypoplastic left heart syndrome are at risk for growth failure, particularly after stage 1 procedures. The effect of continuous enteral feedings on weight gain has not been previously investigated. METHODS: A randomized controlled trial was performed in infants with hypoplastic left heart syndrome and single ventricle variants after stage 1 procedures. Eligible infants were randomized to a continuous and intermittent feeding regimen or an exclusive intermittent feeding regimen after stage 1 procedures and continued until hospital discharge. Anthropometric measures and markers of nutritional status were assessed throughout hospitalization. RESULTS: Twenty-six infants completed the study. There were no significant differences in weight gain, growth, or nutritional status. Weight gain on full enteral feedings was 24.3 versus 23.6 g/d (P = .88) for the combination (continuous and intermittent) versus intermittent feeding groups. Weight-for-age Z scores at discharge were -1.37 versus -1.2 (P = .59) for the combination versus intermittent groups. CONCLUSIONS: No significant differences in weight gain, growth, or nutritional status were observed at hospital discharge between the two feeding strategies. Despite both groups achieving target daily weight gain after attaining full feeds, growth failure continued to be a problem after stage 1 procedures. Further strategies to improve growth during initial hospitalization are needed.

Comparison of impedance measurements near the skin of newborns and adults.

Electrical impedance tomography (EIT) is a non-invasive imaging technology that has been extensively studied for monitoring lung function of neonatal and adult subjects, especially in neonatal intensive care unit (NICU) and intensive care unit (ICU) environments. The sources of the total impedance in these applications include internal organs, near-boundary tissues, electrode-skin impedance, electrodes and conducting wires. This total impedance must be considered for system design and setting voltage gain since it will contribute to the measured voltage. To adapt a single instrument for use on infants and adults, we studied the difference between the impedance near the skin in both classes of patients. We used a simultaneous multi-source EIT (SMS-EIT) system to make impedance measurements. Characteristic resistance was calculated for two different current patterns: one that is more sensitive to boundary region impedance and another that is more sensitive to interior changes. We present ratios of these resistances to assess the relative contribution of near-skin effects to the overall impedance. Twenty adult ICU subjects (10 male, 10 female, age: 49.05 ± 16.32 years (mean ± standard deviation)) and 45 neonates (23 male, 22 female, gestational age: 37.67 ± 2.11 weeks, postnatal age, 2.56 ± 2.67 d) were studied at Columbia University Medical Center. Impedance measurements at 10 kHz were collected for approximately one hour from each subject. The characteristic resistance ratio for each subject was computed and analyzed. The result shows the impedance at or near the skin of newborns is significantly higher than in adult subjects.