Early Hypophosphatemia in High-Risk Preterm Infants: Efficacy and Safety of Sodium Glycerophosphate From First Day on Parenteral Nutrition

Background: Early hypophosphatemia is common in premature infants ≤1250 g. The aim of this study was to assess the frequency and severity of hypophosphatemia after sodium glycerophosphate supplementation from first day of life in parenteral nutrition and to address the safety of this practice.

Methods: Prospective cohort study of infants ≤1250 g birth weight born in a tertiary-care level neonatal intensive care unit and supplied with sodium glycerophosphate from the first day of life. Primary outcome was the presence of hypophosphatemia (<4 mg/dL) on the first week. Data were compared with our 2014 prospective subcohort of infants ≤1250 g receiving phosphate after 48 hours of life and morbidity with that of our 2016 retrospective cohort of ≤1250 g.

Results: Fifty-four neonates were included. The frequency of hypophosphatemia was 29.6%. Only 1 patient presented hypophosphatemia <2 mg/dL. Mild hypokalemia was found in 8 patients (50%). No cases of hypernatremia were observed. Patients with hypophosphatemia had significantly lower gestational age (27.4 vs 28.8 weeks, P = .032) and lower z-score birth weight (-1.68 vs -0.47; P = .001). When compared with the 2014 subcohort, we found a lower frequency of hypophosphatemia (29.6% vs 69.2%; P = .008) and a lower rate of samples with hypophosphatemia (20.4% vs 51.4%; P = .0002) and critical hypophosphatemia (0.68% vs 11.4%, P = .0005). No differences were found in morbidity or mortality.

Conclusions: Sodium glycerophosphate supplementation in parenteral nutrition from the first day of life significantly decreased the frequency of hypophosphatemia. No adverse events were reported.