Sudden Neurologic Worsening.

Generating a comprehensive, yet focused, differential diagnosis for sudden neurologic worsening in the postoperative patient can be challenging. It must take into consideration the procedure itself, the structures manipulated, preceding events, the timing of the neurologic decline, and the patient's medical history. A thorough understanding of these factors facilitates evaluation and intervention to address reversible etiologies. Nonstructural causes of encephalopathy are common and include toxic-metabolic insults and hypoxia or hypercapnia, as well as iatrogenic phenomena such as overnarcotization and intensive care unit delirium-all of which may influence neurologic status and are potential confounders.