Prospective Observational Multimodal Neuromonitoring During High-Risk Adult Surgery

Inclusion Criteria: * Age 18 years or older * Scheduled to undergo major spine surgery, liver transplantation, on-pump cardiac surgery, major vascular surgery, major thoracic surgery, major abdominal surgery, or neurosurgical craniotomy at UT Southwestern Medical Center * Able to provide informed consent (self or legally authorized representative when applicable) * Safe and feasible placement of SedLine and/or Brain4Care monitoring as determined by the clinical and research teams * Anticipated availability of perioperative clinical data needed for study analyses Exclusion Criteria: * Age younger than 18 years * Prisoner status * Pregnancy * Unable to provide informed consent in English (consent documents available in English only) * Declining participation * Lack of subject or legally authorized representative consent when required * Clinical condition preventing safe or feasible placement of study monitors (e.g., incompatible surgical field location, significant facial or scalp injury, open wounds at intended sensor placement site) * Operative workflow or clinical urgency precluding reasonable completion of consent and monitor placement prior to start of surgery * Anticipated clinical data capture insufficient for meaningful analysis