Amino acid infusions in umbilical artery catheters enhance protein administration in infants born at extremely low gestational age

Early Amino Acids in Extremely Preterm Infants and Neurodisability at 2 Years

BACKGROUND

Whether higher parenteral amino acid intake improves outcomes in infants with extremely low birth weight is unclear.

METHODS

In this multicenter, parallel-group, double-blind, randomized, placebo-controlled trial, we assigned infants with birth weights of less than 1000 g at 8 neonatal intensive care units to receive amino acids at a dose of 1 g per day (intervention group) or placebo in addition to usual nutrition for the first 5 days after birth. The primary outcome was survival free from neurodisability as assessed with the Bayley Scales of Infant and Toddler Development and neurologic examination at 2 years, corrected for gestational age at birth. Secondary outcomes were the components of the primary outcome as well as the presence or absence of neonatal disorders, the rate of growth, and nutritional intake.

RESULTS

We enrolled 434 infants (217 per group) in this trial. Survival free from neurodisability was observed in 97 of 203 children (47.8%) in the intervention group and in 102 of 205 (49.8%) in the placebo group (adjusted relative risk, 0.95; 95% confidence interval [CI], 0.79 to 1.14; P = 0.56). Death before the age of 2 years occurred in 39 of 217 children (18.0%) in the intervention group and 42 of 217 (19.4%) in the placebo group (adjusted relative risk, 0.93; 95% CI, 0.63 to 1.36); neurodisability occurred in 67 of 164 children (40.9%) in the intervention group and 61 of 163 (37.4%) in the placebo group (adjusted relative risk, 1.16; 95% CI, 0.90 to 1.50). Neurodisability was moderate to severe in 27 children (16.5%) in the intervention group and 14 (8.6%) in the placebo group (adjusted relative risk, 1.95; 95% CI, 1.09 to 3.48). More children in the intervention group than in the placebo group had patent ductus arteriosus (adjusted relative risk, 1.65; 95% CI, 1.11 to 2.46). In a post hoc analysis, refeeding syndrome occurred in 42 of 172 children in the intervention group and 26 of 166 in the placebo group (adjusted relative risk, 1.64; 95% CI, 1.09 to 2.47). Eight serious adverse events occurred.

CONCLUSIONS

In infants with extremely low birth weight, extra parenteral amino acids at a dose of 1 g per day for 5 days after birth did not increase the number who survived free from neurodisability at 2 years. (Funded by the New Zealand Health Research Council and others; ProVIDe Australian New Zealand Clinical Trials Registry number, ACTRN12612001084875.).

The Impact of Restricted versus Liberal Early Fluid Volumes on Plasma Sodium, Weight Change, and Short-Term Outcomes in Extremely Preterm Infants

The optimal fluid requirements for extremely preterm infants are not fully known. We examined retrospectively the fluid intakes during the first week of life in two cohorts of extremely preterm infants born at 22-26 weeks of gestation before (n = 63) and after a change from a restrictive to a more liberal (n = 112) fluid volume allowance to improve nutrient provision. The cohorts were similar in gestational age and birth weight, but antenatal steroid exposure was more frequent in the second era. Although fluid management resulted in a cumulative difference in the total fluid intake over the first week of 87 mL/kg (p < 0.001), this was not reflected in a mean weight loss (14 ± 5% at a postnatal age of 4 days in both groups) or mean peak plasma sodium (142 ± 5 and 143 ± 5 mmol/L in the restrictive and liberal groups, respectively). The incidences of hypernatremia (>145 and >150 mmol/L), PDA ligation, bronchopulmonary dysplasia, and IVH were also similar. We conclude that in this cohort of extremely preterm infants a more liberal vs. a restricted fluid allowance during the first week had no clinically important influence on early changes in body weight, sodium homeostasis, or hospital morbidities.