Postoperative Delirium: A Comprehensive Review

Postoperative delirium (POD) is a common acute neuropsychiatric complication following surgery, especially in older patients. Characterized by fluctuating disturbances in attention, awareness, and cognition, POD typically occurs within days after surgery and can last days to weeks. Its pathophysiology involves neuroinflammation, neurotransmitter imbalances, blood-brain barrier disruption, and oxidative stress. Key risk factors include advanced age, baseline cognitive impairment, comorbidities, surgical complexity, environmental factors and excessive deep anesthesia. Incidence varies by surgical type, with highest rates in cardiac surgery (~23%) and hip fracture repair (30-50%). Prevention strategies encompass nonpharmacological approaches (early mobilization, reorientation, sleep promotion) and pharmacological interventions (optimized anesthesia, dexmedetomidine, melatonin). For established delirium, management focuses on treating underlying causes, supportive care, and judicious use of antipsychotics for severe agitation. Beyond its immediate impact, POD is associated with concerning long-term outcomes: accelerated cognitive decline, increased dementia risk, functional deterioration, and higher mortality. Studies show patients who experience POD have a 40% faster rate of cognitive decline and approximately double the mortality risk within one year compared to non-delirious patients. This relationship with adverse outcomes underscores that POD is not a transient phenomenon; rather, it may be a pivotal event in a patient’s long-term health trajectory. Implementation of evidence-based prevention and management protocols is essential to improve perioperative outcomes in our aging surgical population.