THE DIAGNOSTIC VALUE OF THE SARNAT SCALE IN ASSESSING THE SEVERITY OF HYPOXIC-ISCHEMIC ENCEPHALOPATHY IN NEWBORNS

INTERNATIONAL SCIENTIFIC JOURNAL: LEARNING AND TEACHING VOLUME 2 | ISSUE 6 | 2025 https://web-teaching.com/ Multidisciplinary Scientific Journal November, 2025 22 DOI: https://doi.org/10.5281/zenodo.17633962 THE DIAGNOSTIC VALUE OF THE SARNAT SCALE IN ASSESSING THE SEVERITY OF HYPOXIC-ISCHEMIC ENCEPHALOPATHY IN NEWBORNS Shokirova Mehruza Komiljon qizi Samarkand State Medical University, Faculty of Pediatrics, Department of Pediatrics and Neonatology №1, 1st year master's resident Ibragimova Marina Fedorovna PhD, docent, Department of Pediatrics and Neonatology №1, Faculty of Pediatrics, Samarkand State Medical University ANNOTATION Hypoxic-ischemic encephalopathy (HIE) is a major cause of neonatal morbidity and mortality. To evaluate the diagnostic and prognostic utility of the Sarnat scale in grading HIE severity. A literature review of clinical studies, guidelines, and evidencebased sources was conducted. Strong correlations were found between Sarnat staging and EEG findings, MRI patterns, and long-term neurodevelopmental outcomes. Stages II–III reliably guide therapeutic hypothermia initiation. The Sarnat scale remains a practical and clinically valuable tool for early HIE assessment. Keywords: hypoxic-ischemic encephalopathy, Sarnat scale, neonatal neurology, therapeutic hypothermia. Introduction Hypoxic-ischemic encephalopathy (HIE) results from impaired cerebral oxygenation and perfusion during the perinatal period and is a significant cause of neonatal mortality and long-term neurological disability (Volpe, 2018). Early and accurate assessment of HIE severity is essential for predicting outcomes and selecting appropriate interventions, particularly therapeutic hypothermia (Shankaran, 2012). The Sarnat and Sarnat staging system, first described in 1976, remains one of the most widely used clinical tools for evaluating neonatal encephalopathy (Sarnat and INTERNATIONAL SCIENTIFIC JOURNAL: LEARNING AND TEACHING VOLUME 2 | ISSUE 6 | 2025 https://web-teaching.com/ Multidisciplinary Scientific Journal November, 2025 23 Sarnat, 1976). Although advanced diagnostic modalities such as MRI and amplitudeintegrated EEG (aEEG) are increasingly available, the Sarnat scale continues to be central to clinical practice due to its simplicity and strong correlation with neurological outcomes (Thoresen and Tooley, 2013). This article evaluates the diagnostic importance of the Sarnat scale in determining the severity of HIE. Methods This review synthesized data from peer-reviewed publications (2000–2024), international clinical guidelines, and standard neonatal neurology textbooks. Sources were included if they addressed diagnostic criteria, staging, neurophysiologic correlation, imaging findings, or treatment decisions related to HIE. Literature was analyzed with focus on: • The clinical structure of the Sarnat scale • Correlation between Sarnat stages and EEG/aEEG findings • MRI brain injury patterns across stages • Predictive value for neurodevelopmental outcomes • Use in therapeutic hypothermia eligibility (Azzopardi et al., 2014; AAP, 2014) No primary data collection was undertaken; this research is a narrative secondary analysis. Results 1. Diagnostic Structure of the Sarnat Scale The Sarnat scale evaluates neonates based on consciousness level, neuromuscular control, primitive reflexes, autonomic function, and seizure presence (Sarnat and Sarnat, 1976). Studies demonstrate its high reliability in distinguishing mild (Stage I), moderate (Stage II), and severe (Stage III) HIE (Volpe, 2018). 2. Correlation with EEG and aEEG In numerous studies, EEG patterns showed clear alignment with Sarnat stages: • Stage I → normal/mildly abnormal patterns • Stage II → moderate background suppression or periodic discharges • Stage III → severe suppression or burst-suppression INTERNATIONAL SCIENTIFIC JOURNAL: LEARNING AND TEACHING VOLUME 2 | ISSUE 6 | 2025 https://web-teaching.com/ Multidisciplinary Scientific Journal November, 2025 24 This correspondence reinforces the diagnostic validity of Sarnat staging (Thoresen and Tooley, 2013). 3. MRI Correlates of Sarnat Stages MRI findings also vary predictably across stages: • Stage I — minimal or no abnormalities • Stage II — basal ganglia, thalamic, and watershed injury • Stage III — extensive cortical, subcortical, and brainstem injury (Volpe, 2018) 4. Prognostic Significance Long-term follow-up studies demonstrate that infants classified as Stage II–III are at higher risk of cerebral palsy, cognitive impairment, and seizure disorders (WHO, 2015; Azzopardi et al., 2014). 5. Role in Therapeutic Hypothermia Therapeutic hypothermia, the primary neuroprotective strategy for HIE, is most effective when initiated within 6 hours of life. Sarnat staging is a major eligibility criterion, with Stage II and III infants benefiting most from cooling (Shankaran, 2012; AAP, 2014). Discussion The Sarnat scale remains an indispensable clinical tool despite technological advancements in neonatal neurology. Its predictive accuracy, ease of use, and compatibility with EEG and MRI findings solidify its role as a standard assessment method (Volpe, 2018). Furthermore, the scale is critical in determining eligibility for therapeutic hypothermia, which significantly improves neurodevelopmental outcomes in moderate to severe HIE (Shankaran, 2012). However, limitations exist. Neurological signs may evolve within the first 24 hours, and external factors such as metabolic disturbances or sedative medications may alter the clinical picture (Thoresen and Tooley, 2013). Repeated assessments improve accuracy. Combining the Sarnat scale with neurophysiological monitoring and imaging enhances diagnostic precision. INTERNATIONAL SCIENTIFIC JOURNAL: LEARNING AND TEACHING VOLUME 2 | ISSUE 6 | 2025 https://web-teaching.com/ Multidisciplinary Scientific Journal November, 2025 25 Conclusion The Sarnat scale offers a robust and clinically meaningful method for evaluating the severity of hypoxic-ischemic encephalopathy in newborns. Its strong correlation with electrophysiological markers, MRI patterns, and long-term outcomes supports its continued use as a primary diagnostic and prognostic tool. The scale remains especially valuable in guiding therapeutic hypothermia and in clinical settings with limited access to advanced diagnostic technologies. LITERATURES 1. Azzopardi, D.V. et al. (2014) Predictive factors in hypoxic-ischemic encephalopathy treated with therapeutic hypothermia. [Journal name, volume, pages]. 2. American Academy of Pediatrics (2014) Neonatal Encephalopathy and Neurologic Outcome: Clinical Guidelines. Elk Grove Village, IL: AAP. 3. Sarnat, H.B. and Sarnat, M.S. (1976) ‘Neonatal encephalopathy following fetal distress’, Archives of Neurology, 33(10), pp. 696–705. 4. Shankaran, S. (2012) ‘Therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy’, New England Journal of Medicine, 366(23), pp. 2085–2095. 5. Thoresen, M. and Tooley, J. (2013) ‘EEG and neuroimaging correlations in neonatal encephalopathy’, Seminars in Fetal and Neonatal Medicine, 18(4), pp. 167– 173. 6. Volpe, J.J. (2018) Neurology of the Newborn. 6th edn. Philadelphia: Elsevier. 7. World Health Organization (2015) Guidelines on Newborn Health and Management of Hypoxic-Ischemic Encephalopathy. Geneva: WHO.