Clinical neonatal hypoxic ischemic injury: Cranial ultrasound spectrum of findings in neonates admitted to a Newborn Unit in Nairobi, Kenya

Abstract

Introduction: Birth asphyxia causes significant neurologic injury and neurodevelopmental delay in children. Cranial ultrasound (CUS) can be used for the diagnosis, early intervention, and prognostication of birth asphyxia. We determined the CUS findings among term neonates with clinical birth asphyxia and correlated sonographic findings with the modified Sarnat clinical grade. Materials and Methods: We conducted a prospective cross-sectional analytical study in Kenyatta National Hospital New Born Unit (KNH NBU) between June 2018 and October 2018. Term babies, older than 24 h with clinical birth asphyxia, were recruited and CUS was performed. Statistical analysis was done using proportions, means, and frequencies. Chi-square tests were used to assess correlation between imaging findings and the clinical Sarnat grading of asphyxia. Results: Periventricular deep white matter echogenicity and thalamus and/or basal ganglia deep gray matter was reported in 56.4% and 31.1%, respectively. Only 4.4% had cortical gray matter. Normal CUS findings were reported in 40.0% of the neonates. Prolonged labor and meconium-stained liquor were the predominant risk factors for perinatal asphyxia, seen in 58% of the neonates. Prolonged labor was independently reported in 43% of the neonates. Moderate and severe Sarnat grades correlated with abnormal sonographic changes of hypoxic ischemic encephalopathy (HIE) (Grades 2–8) (P = 0.038). There was a trend toward HIE severity with worsening Sarnat stages (trend test P= 0.039). Abnormal resistive indices (<0.5 and >0.8) were strongly associated with the presence of HIE brain changes (P = 0.003). Conclusion: The correlation between birth asphyxia severity and CUS was more robust in Doppler evaluation of the deep cerebral arteries.