Somatic growth outcomes in response to an individualized neonatal sodium supplementation protocol

Evaluate the impact of a sodium (Na) supplementation protocol based upon urine Na concentration on growth parameters and morbidities.

Retrospective cohort study of infants 26^0/7-33^6/7 weeks gestational age (GA) cared for before (2012–15, n = 310) and after (2016–20, n = 382) implementation of the protocol. Within- and between-group changes over time were assessed using repeated measures generalized linear models.

For infants 26^0/7-29^6/7 weeks GA, utilization of the protocol was associated with increased mean body weight z-score at 8-weeks postnatal age, increased mean head circumference z-score at 16-weeks postnatal age, and decreased time on mechanical ventilation (all p < 0.02). No impact on growth was identified for infants 30–33^6/7 weeks GA. Incidences of hypertension, hypernatremia, bronchopulmonary dysplasia, necrotizing enterocolitis, and culture positive sepsis were unaffected by the protocol.

Protocolized Na supplementation is associated with improved growth and reduced time on invasive mechanical ventilation in extremely preterm infants without increasing incidence of morbidities.