Increased risk of refeeding syndrome-like hypophosphatemia with high initial amino acid intake in small-for-gestational-age, extremely-low-birthweight infants.

BACKGROUND: Recent nutrition guidelines for extremely-low-birth-weight infants (ELBWIs) recommend implementation of high initial amino acid (AA) supplementation in parenteral nutrition. OBJECTIVE: We sought to evaluate the influence of AA intake on refeeding syndrome-like electrolyte disturbances including hypophosphatemia in ELBWIs. STUDY DESIGN: Medical records of 142 ELBWIs were reviewed. Demographic, nutritional, outcome, and electrolyte data were compared between ELBWIs with initial low (1.5 g/kg/day) and high (3 g/kg/day) AA intake. Multivariate analysis was conducted to determine the odds ratio of hypophosphatemia with high AA intake and small-for-gestational-age (SGA) ELBWIs. RESULTS: The incidence of hypophosphatemia and severe hypophosphatemia increased from 51% and 8% in period I to 59% and 20% in period II, respectively (p = 0.36 and < 0.01). Specifically, SGA ELBWIs showed higher incidence of hypophosphatemia than appropriate-for-gestational age (AGA) ELBWIs in period II, whereas there was no difference in period I. For severe hypophosphatemia, SGA ELBWIs presented a 27% incidence versus a 2% incidence in AGA ELBWIs, even with low initial AA intake. Despite no difference in phosphate intake between infants with and without hypophosphatemia, serum phosphate level reached a nadir at the sixth postnatal day and gradually recovered over the second week in infants with hypophosphatemia. In multivariate analyses, the odds ratios for severe hypophosphatemia were 3.6 and 6.6 with high AA intake and SGA status, respectively, with the highest being 18.0 with combined high AA intake and SGA status. CONCLUSIONS: In summary, high initial AA intake significantly increased the risk of refeeding syndrome-like electrolyte dysregulations including severe hypophosphatemia in ELBWIs. In SGA ELBWIs, the risk of electrolyte disturbance was significantly higher, even with low initial AA intake. Therefore, new tailored parenteral nutrition protocols starting with lower energy intake and a gradual increase over the first week may be warranted for application in high-risk SGA ELBWIs.

Feeding extremely low birth weight infants.

CME EDUCATIONAL OBJECTIVES: 1.List the indications for parenteral nutrition in the preterm infant.2.Estimate protein and calories required by a preterm infant to support appropriate fetal weight gain.3.Discuss the calcium and phosphorus needs of preterm infants. The patient presented as a 5-week-old 26 week preterm infant, with a birth weight of 686 g. Her mother was 25 years old. The child's Apgar scores were 6 and 7 at 1 and 5 minutes. The infant was intubated after birth and placed on the high-frequency oscillator on day of life (DOL) 3 because of worsening respiratory failure. She was placed back on conventional mechanical ventilation on DOL 7, extubated on DOL 15, and placed on 40% oxygen via nasal cannula. She was discharged home on DOL 84 without mechanical ventilation.

Clinical metabolomics and urinary NGAL for the early prediction of chronic kidney disease in healthy adults born ELBW.

BACKGROUND: Clinical metabolomics is a recent "omic" technology which is defined as a global holistic overview of the personal metabolic status (fingerprinting). This technique allows to prove metabolic differences in different groups of people with the opportunity to explore interactions such as genotype-phenotype and genotype-environment type, whether normal or pathological. AIM: To study chronic kidney injury 1) using urine metabolomic profiles of young adults born extremely low-birth weight (ELBW) and 2) correlating a biomarker of kidney injury, urinary neutrophil gelatinase-associated lipocalin (NGAL), in order to confirm the metabolomic injury profile. METHOD: Urine samples were collected from a group of 18 people (mean: 24-year-old, std: 4.27) who were born with ELBW and a group of 13 who were born at term appropriate for gestational age (AGA) as control (mean 25-year-old, std: 5.15). Urine samples were analyzed by (1)H-nuclear magnetic resonance spectroscopy, and then submitted to unsupervised and supervised multivariate analysis. Urine NGAL (uNGAL) was measured using ARCHITECT (ABBOTT diagnostic NGAL kit). RESULTS: With a multivariate approach and using a supervised analysis method, PLS-DA, (partial least squares discriminant analysis) we could correlate ELBW metabolic profiles with uNGAL concentration. Conversely, uNGAL could not be correlated to AGA. CONCLUSIONS: This study demonstrates the relevance of the metabolomic technique as a predictive tool of the metabolic status of exELBW. This was confirmed by the use of uNGAL as a biomarker which may predict a subclinical pathological process in the kidney such as chronic kidney disease.

Results of extremely-low-birth-weight infants randomized to receive extra enteral calcium supply.

BACKGROUND AND OBJECTIVE: Bone mineral deficiency continues to occur in extremely-low-birth-weight (ELBW) infants despite formulas enriched in calcium (Ca) and phosphorus (P). This study tested whether extra enteral Ca supplementation increases bone mineral content (BMC) and prevents dolichocephalic head flattening and myopia in ELBW infants. STUDY DESIGN: Infants 401 to 1000 birth weight receiving enteral feeds were randomized to receive feeds supplemented with Ca-gluconate powder or pure standard feeds. The main outcome measures were the excretion of Ca and P by weekly spot urine measurements, the degree of dolichocephalic deformation (fronto-occipital diameter to biparietal diameter ratio, FOD/BPD) at 36 weeks postmenstrual age, and the BMC (by dual-energy x-ray absorptiometry) at discharge. Cycloplegic refraction was measured at 18 to 22 months corrected age. PATIENTS AND RESULTS: Ninety-nine ELBW infants with a gestational age of 26 weeks (23-31) (median [minimum-maximum]) were randomized at a postnatal age of 12 days (5-23) weighing 790 g (440-1700). Urinary Ca excretion increased and P excretion decreased in the Ca-supplemented group. Total BMC was 89.9 ± 2.4 g (mean ±â€ŠSE) in the supplemented group and 85.2 ± 2.6 g in the control group (P = 0.19). The FOD/BPD was 1.50 (1.13-1.69, mean ± SD [standard deviation]) and 1.47 (1.18-1.64) in the supplemented and control groups, and the refraction 0.98  ± 1.23 and 1.40 ± 1.33 dpt (P = 0.68), respectively in 64 ELBW infants (79% of survivors) at 2-year follow-up. CONCLUSIONS: Extra enteral Ca supplementation did not change BMC, head shape, or refraction. The decreased P excretion may reflect P deficiency in infants receiving extra Ca, preventing improved bone mineral accretion.

Metabolic responses to early and high protein supplementation in a randomized trial evaluating the prevention of hyperkalemia in extremely low birth weight infants.

OBJECTIVE: To determine whether early and higher intravenous amino acid (EHAA) supplementation decreases hyperkalemia in extremely low birth weight (ELBW) infants (<1000 g). STUDY DESIGN: Infants were enrolled at birth in a randomized, double-masked, prospective fashion and treated for 7 days. The standard group (SAA) infants received intravenous amino acid (AA) starting at 0.5 g x kg(-1) x d(-1) and increased by 0.5 g x kg(-1) every day to a maximum of 3 g x kg(-1) x d(-1). EHAA group infants received 2 g x kg(-1) x d(-1) of AA soon after birth and advanced by 1 g x kg(-1) every day to 4 g x kg(-1) x d(-1). Data analysis was by SPSS 11.5, with statistical significance at alpha = 0.05 and 90% power to determine a difference in mean K(+) level of 2. RESULTS: Sixty-two patients, mean gestational age of 26.0 +/- 2.0 weeks and birth weight of 775 +/- 136 g, were enrolled. Hyperkalemia (K(+) > or =6.5 mEq/L) occurred in 13% of the studied population; no difference in incidence of hyperkalemia was found between the SAA and EHAA groups (16% vs 10%, respectively, P = .70). Serum blood urea nitrogen was higher in the EHAA group. AA infusion was stopped early in 6 patients for high blood urea nitrogen or elevated ammonia level. CONCLUSIONS: During the study period, hyperkalemia decreased significantly and was not affected by EHAA supplementation in the first week of life.

The corrected blood urea nitrogen predicts the developmental quotient of extremely low-birth-weight infants at the corrected age of 36 months.

BACKGROUND: Currently, there are no nutritional indices to predict cognitive function in extremely low-birth-weight (ELBW) infants. OBJECTIVE: To assess the neonatal blood urea nitrogen (BUN) values in ELBW infants according to their cognitive function at the corrected age of 36 months. METHODS: This was a retrospective study that assessed the neonatal factors affecting the developmental outcome in two groups "developmental quotient (DQ)> or =80" and "DQ<80", the groups were divided based on the DQ at the corrected age of 36 months. Between 1996 and 1999, 178 ELBW infants born at <28 weeks of gestation were admitted to our neonatal intensive care unit (NICU), of these, 32 died. Of the surviving 146 infants, 37 infants without any exclusion criteria (that would affect the cognitive function and BUN) except the nutritional factor, were assessed. Area under the curve (AUC) of corrected BUN (CBUN: BUN x 0.5/serum creatinine) from 28 to 84 days of life was used as an index of protein intake. RESULTS: No significant differences were observed between the two groups with regard to the gestational age, birth weight, Z score of birth weight, and sex. However, compared to 15 infants with DQ<80, 22 infants with DQ> or =80 had significantly shorter duration of artificial ventilation and O(2) supplementation, a higher Apgar score at 5 min, and a higher AUC of CBUN. On multiple regression analysis, DQ> or =80 was observed to be significantly correlated with the AUC of CBUN (Odd's ratio 1.03, 95% confidence interval: 1.002-1.06). CONCLUSION: The CBUN level would provide an estimate of adequate protein intake and the subsequent development of an ELBW infant.