[Early hypophosphataemia in at risk newborns. Frequency and magnitude]

Neonatal Refeeding Syndrome and Clinical Outcome in Extremely Low-Birth-Weight Babies: Secondary Cohort Analysis From the ProVIDe Trial

BACKGROUND

Refeeding syndrome (RS) following preterm birth has been linked to high intravenous (IV) protein intake in the presence of low electrolyte supply. In extremely low-birth-weight (ELBW) babies, we aimed to determine the incidence of RS and associations with birth characteristics and clinical outcomes.

METHOD

Prospective cohort study of ELBW ProVIDe Trial participants in 6 New Zealand neonatal intensive care units. RS was defined as serum phosphate < 1.4 mmol.L^-1 and total calcium > 2.8 mmol.L^-1 . Relationships between RS and other factors were explored using 2-sample tests and logistic regression adjusted for sex, gestation, and birth-weight z-score.

RESULTS

Of 338 babies (mean [SD] birth-weight, 780 (134) g, gestational age, 25.9 [1.7] weeks), 68 (20%) had RS. Mortality was greater in babies with RS (32% vs 11%; P < .0001). More small- than appropriate-for-gestational-age babies developed RS (22% vs 8%; P = .001). Growth from birth to 36 weeks' corrected age was not different between babies who did and did not have RS. In logistic regression, the odds of RS decreased by 70% for each 1 mmol per kg^-1 .d^-1 IV phosphate intake (odds ratio [OR], 0.3; CI, 0.1-0.6; P = .002) and increased by 80% for each 1 g.kg^-1 .d^-1 IV protein intake (OR, 1.8; CI, 1.3-2.7; P = .002).

CONCLUSIONS

Neonatal RS is common in this cohort of ELBW babies and is associated with increased morbidity and mortality. Optimizing phosphate and calcium intakes in IV nutrition solutions may reduce RS and its consequences.

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.