Association between impaired renal function based on decline in serum creatinine level and brain injury in neonates...

Impaired renal function (IRF), defined as the rate of decline in serum creatinine levels during the week after birth, frequently affects neonates with moderate or severe hypoxic-ischemic encephalopathy (HIE). However, its clinical relevance in this vulnerable population requires further investigation.

This study aimed to evaluate the association between IRF and brain injury severity in neonates with HIE.

This retrospective single-center study included neonates treated with therapeutic hypothermia for moderate or severe HIE. A multivariable logistic regression analysis evaluated the association between IRF and the combined outcomes of early death or severe brain injury (ED/SevereBI).

Of the 147 included neonates, 67 (45.6%) had IRF and 32 (22%) had ED/SevereBI. Those with ED/SevereBI were more likely to have a lower 5-min Apgar score (median [interquartile range]: 4 [2-5] vs. 2 [1-3], P<0.01), have a higher initial blood lactate level (mean cord blood lactate level, +34%, P<0.05), be intubated in the delivery room (50% vs. 75%, P=0.01), and have IRF (39% vs. 69%, P<0.01). After the adjustment for neonatal characteristics and perinatal asphyxia parameters, neonates with IRF had a 2- to 3-fold higher odds of ED/SevereBI than those without IRF (adjusted odds ratio [95% confidence interval]: 2.66 [1.09-6.84], P=0.03).

In neonates treated with therapeutic hypothermia for HIE, IRF can be used as a marker of adverse outcomes. Further studies are required to evaluate its long-term prognostic value.