Postoperative psychosis is most likely to occur in a patient with which history?

• A. Chronic pain syndrome
• B. Sleep deprivation
• C. Recent surgery requiring anesthesia
• D. Substance intoxication

Answer: (C)

Postoperative delirium is an acute confusional state that commonly follows surgery with anesthesia. The recent history of undergoing surgery requiring anesthesia best explains a postoperative psychosis because the perioperative period brings multiple delirium triggers: the brain’s response to anesthesia, postoperative pain and analgesic use (often opioids), sleep disruption, fluid and electrolyte shifts, infection, metabolic changes, and polypharmacy. These factors together can quickly disrupt attention and cognition, producing delirium with possible psychotic features, especially in older or cognitively vulnerable patients.

Chronic pain syndrome, sleep deprivation alone, or substance intoxication can contribute to confusion in various settings, but they do not specifically point to the postoperative context as the trigger. Recognize delirium by sudden onset, fluctuating alertness, inattention, and disorganized thinking, and manage by addressing underlying causes, optimizing hydration and oxygenation, minimizing deliriogenic medications, and using supportive measures or antipsychotics if agitation is unsafe.