“Multimodal Neuromonitoring and Cerebral Autoregulation Assessment in Neonatal and Pediatric Intensive Care”

As survival of critically ill neonates and children has improved over recent decades through remarkable advances in pediatric intensive care, increasing attention has shifted toward the prevention of secondary brain injury and the preservation of long-term neurodevelopment. Nevertheless, neurological injury remains a major threat, often arising from dynamic interactions between systemic instability, impaired cerebral perfusion, and limited cerebrovascular reserve. This thesis explores the role of multimodal neuromonitoring as an integrated physiological framework for individualized brain-oreinted care in pediatric critical illness, with a specific focus on continuous cerebral autoregulation assessment. The first part of the work reviews the principles, tools, and clinical rationale of multimodal neuromonitoring in neonatal and pediatric intensive care, emphasizing the limitations of isolated physiological thresholds and the need for patient-specific targets. The second part examines the physiological basis and methodological approaches of cerebral autoregulation monitoring, including invasive pressure reactivity index-based assessment and non-invasive near-infrared spectroscopy-derived indices. The final part presents complementary research lines in two high-risk pediatric populations. In children with severe traumatic brain injury, intracranial pressure-based autoregulation monitoring provided insight into cerebrovascular reactivity and highlighted the limitations of fixed cerebral perfusion pressure targets. In neonates and infants undergoing cardiac surgery for congenital heart disease, near-infrared spectroscopy-based autoregulation monitoring demonstrated reproducible, phase-dependent impairment across the perioperative period and identified clinically relevant associations between exposure to arterial pressure below individualized autoregulatory thresholds and markers of brain injury. Ongoing work in pediatric extracorporeal membrane oxygenation further extends this approach to a population characterized by profound hemodynamic instability and high neurological vulnerability. Overall, this thesis supports the view that cerebral autoregulation is a dynamic and context-dependent process whose continuous assessment may provide greater physiological specificity than population-based thresholds. The integration of autoregulation monitoring with multimodal data streams, advanced signal processing, and real-time decision-support tools may help translate precision physiology into individualized neuroprotective strategies for critically ill children, with the ultimate goal of reducing neurological complications and improving long-term neurodevelopmental outcomes.