Resistive Index as an Early Prognostic Marker in Term Neonates with Perinatal Asphyxia: Correlation with Hypoxic-Ischemic Encephalopathy Staging

Background: Perinatal asphyxia and hypoxic-ischemic encephalopathy (HIE) are serious neonatal morbidity and mortality conditions. Early prognostic markers are necessary for intervention and for predicting outcome. The Resistive Index (RI), assessed by cranial Doppler ultrasound, has emerged as a possible non-invasive bedside device for measuring cerebral hemodynamics. This is study to determine the estimation of RI in term infants with perinatal asphyxia and its correlations with HIE staging and short-term conditions of the neurological outcomes. Material and Methods: The study was a prospective observational study that involved 130 term neonates (37 weeks) with perinatal asphyxia who were hospitalized after delivery at less than 24 hours. Doppler ultrasound was used to measure RI of the first 24 hours in life. HIE was assessed based on the Sarnat and Sarnat standards. The Short Hammersmith Neonatal Neurological Examination (HNNE) was used to determine neurological outcomes at 40 days. Chi-square tests and ROC curve analysis were used in the statistical analysis. Results: In 130 neonates, 56.9% had normal RI; 6.2%, 19.2%, and 17.7% showed mild, moderate, and severe RI exemptions, respectively. The need for TM: there was a significant relationship between RI and HIE grade (P=0.001), with 85.7% of HIE Grade 1 neonates demonstrating normal RI, compared with 51.3% of Grade 3 neonates demonstrating severe RI. Severe RI was equated with a mortality incidence of 60.9 (P=0.001). Analysis of the ROC curve indicated that RI had an AUC of 0.949, predicting mortality with an optimal cutoff of 0.55 (sensitivity = 100, specificity = 92.24). The failure rates of HNNE were dependent on the severity of the HIE (30.6% in Grade 1, 87.0% in Grade 3, P=0.001) and significantly associated with abnormal RI (P=0.001). Conclusion: The evidence-based practice RI is a valid, non-invasive early prognostic in neonates with perinatal asphyxia. An RI of less than 0.55 is a good prognosticator of mortality and adverse neurological prognosis. Longitudinal RI measurements should be assessed in conjunction with clinical evaluation to inform early therapeutic interventions, especially in resource-constrained environments. Keywords: Resistive Index, Perinatal Asphyxia, Hypoxic-Ischemic Encephalopathy, Doppler Ultrasound, Neonatal Outcomes, Hammersmith Examination.