Sodium supply from administered blood products was associated with severe intraventricular haemorrhage in extremely preterm infants

AIM: The aim of this study was to investigate the associations between sodium supply, fluid volume, sodium imbalances and severe intraventricular haemorrhage (IVH) in extremely preterm (EPT) infants. METHODS: We used data from the EXtremely PREterm infants in Sweden Study (EXPRESS) cohort consisting of all infants born at 22 to 26 gestational weeks from 2004 to 2007 and conducted a nested case–control study. For every infant with severe IVH (grade 3 or peri‐ventricular haemorrhagic infarction), one IVH‐free control infant with the birthday closest to the case infant and matched for hospital, sex, gestational age and birth weight was selected (n = 70 case–control pairs). RESULTS: Total sodium supply and fluid volume were higher in infants with severe IVH compared with controls [daily total sodium supply until postnatal Day 2: mean ± SD (mmol/kg/day): 5.49 ± 2.53 vs. 3.95 ± 1.91, p = 0.009]. These differences were accounted for by sodium and fluid from transfused blood products. High plasma sodium concentrations or large sodium fluctuations were not associated with severe IVH. CONCLUSION: Our results suggest a relationship between sodium‐rich transfusions of blood products and severe IVH in EPT infants. It is unclear whether this is an effect of sodium load, volume load or some other transfusion‐related factor.