Renal profile of asphyxiated neonates in relation to the severity of asphyxia

Abstract

Background and Objectives:Perinatal asphyxia (PA) is a major problem that contributes significantly to neonatal mortality as well as long term morbidity.Due to their unique characteristics, neonatalKidneys are one of the most common organs involved in multiple organ dysfunction caused by asphyxia. Whereas renal complications in perinatal asphyxia have been well studied, literature regarding degree of renal dysfunction in relation to severity of asphyxia is sparse. This study was conducted to determine the incidence of renal failure in asphyxiated neonates and to correlate severity and type of renal failure with APGAR score and hypoxic ischemic encephalopathy (HIE) grading of neonates.Methodology: This prospective case control study was conducted over 1 year from July 2019 to June 2020 at NICU of our tertiary care hospital. Consecutively admitted neonates of gestational age >34 weeks with PA formed the study group who were carefully matched with equal number of non-asphyxiated neonates of comparable gestational age, weight & gender. Renal function was assessed by urine output, urine microscopy, biochemical parameters & sonographic findings. Observation and Results: 102 asphyxiated neonates were enrolled as cases (group A) in the present study. Of these asphyxiated neonates, 58 (56.9%) had hypoxic ischemic encephalopathy (HIE). Urine output in group A was 1.23 mL ± 0.41 mL/kg/hour which was comparable to 1.31 mL ± 0.39 mL/kg/hour in the control group (P = 0.15). Blood urea and serum creatinine were significantly higher in asphyxiated babies as compared to the control group (P<0.05). Concentration of urea and creatinine increased with progression of the HIE stage. This trend was statistically significant between babies with no HIE and those with HIE stage III (P <0.05). Neonates with asphyxia also had significantly higher incidence of hyponatremia (30.4% vs 10.8%). 44.1% neonates had acute renal failure. Non-oliguric renal failure (29/45, 64.4%) was more common than oliguric renal failure (16/45, 35.6%). Neonates with oliguric renal failure had higher mortality rate. Renal parameters normalized in all survivors by 1 months of age.Conclusion: Renal failure is a significant problem in asphyxiated neonates with majority of neonates having non-oliguric renal failure. Severity of renal function abnormality correlates well with degree of asphyxia.