Factors Affecting Mortality in Cases of Perinatal Asphyxia Treated with Hypothermia;a 10-Year Experience; A Retrospective Cohort Study

Introduction: Birth asphyxia and intrapartum brain injury can cause death or irreversible brain damage. The only known treatment that has been shown to improve prognosis is therapeutic hypothermia. Our goal was to assess the parameters associated with death in newborns receiving therapeutic hypothermia. Methods: This retrospective cohort study was conducted in a neonatal intensive care unit and included neonates who underwent therapeutic hypothermia due to perinatal asphyxia over ten years. Patients were categorized into survivors and non-survivors based on in-hospital outcomes. Demographic characteristics, clinical parameters, laboratory findings, and complications were retrieved from medical records. Prognostic factors were compared between groups using appropriate statistical methods, and multivariate logistic regression was performed to identify independent predictors of mortality. Results: A total of 114 newborns treated with therapeutic hypothermia were analyzed, of whom 11 (9.6%) died due to perinatal asphyxia (PA). Non-survivors had significantly lower gestational age (37±2 vs. 38.4±1.6 weeks, p=0.042), lower 5-minute Apgar scores [5 (1–5) vs. 5.5 (4–7), p=0.048], and higher cesarean delivery rates (81.8% vs. 41.7%, p=0.011). Severe findings on aEEG and Sarnat Stage 3 were more common among non-survivors (p<0.001 for both). Non-survivors also exhibited significantly lower admission rectal temperatures [33.8°C (32–36) vs. 35.8°C (34.5–36), p=0.023], higher rates of thrombocytopenia (81.8% vs. 42.7%, p=0.013), acute renal failure (90.9% vs. 39.8%, p=0.001), and cranial ultrasound abnormalities (27.3% vs. 3.9%, p=0.019). In multivariate logistic regression analysis, only lower admission rectal temperature remained an independent predictor of mortality (OR: 1.520, 95% CI: 1.061–2.178, p=0.023). Conclusion: Factors such as lower Apgar scores, acute renal failure, and hypothermia severity on admission are strongly associated with mortality. Early identification and management of these risk factors are critical for improving outcomes in neonates treated with therapeutic hypothermia.