Which combination of factors predisposes elderly patients to postoperative delirium?

• A. Young age, no medical problems
• B. Age, baseline cognitive impairment, infection, polypharmacy
• C. Short anesthesia duration only
• D. Absence of delirium risk factors

Answer: (B)

Recognizing risk factors that predispose elderly patients to postoperative delirium. Age lowers physiologic reserve and makes the brain more vulnerable to delirium after surgery. Baseline cognitive impairment signals reduced cognitive reserve, so even routine stressors from surgery, analgesia, or sleep disruption can precipitate delirium. An active infection provides a systemic inflammatory insult that can precipitate delirium in a susceptible brain. Polypharmacy increases exposure to anticholinergic burden and drug interactions, worsening cognitive function and delirium risk. When these factors are present together, the likelihood of postoperative delirium is markedly higher than with any single factor.