Delirium Superimposed on Dementia in the Hospital
Mrs. R is an 88-year-old woman with moderate Alzheimer's disease (MMSE 16/30) who is admitted to the hospital for a hip fracture after a fall. She is on donepezil 10 mg daily. Postoperatively, she becomes acutely confused, agitated, and is trying to climb out of bed. She is disoriented to time and place, and her speech is incoherent. Vital signs: T 37.8°C, HR 110, BP 150/90, RR 22, SpO2 94% on room air. Labs show mild leukocytosis (WBC 11.5), and urinalysis is positive for nitrites and leukocyte esterase. She is not on any new medications except for postoperative opioids (morphine PCA).
1. What is the most likely diagnosis, and what are the contributing factors?
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The patient has delirium superimposed on dementia. The acute onset and fluctuating course, inattention, disorganized thinking, and altered level of consciousness are hallmarks. Contributing factors include: urinary tract infection (positive urinalysis), pain and opioid use (morphine PCA), possible dehydration, sensory deprivation (hospital environment), and change in routine. The hip fracture and surgery themselves are stressors. The donepezil may have been withheld during hospitalization, contributing to cognitive worsening. Delirium is a medical emergency and requires prompt identification and treatment of underlying causes.
2. Outline your management plan for this patient's delirium, including both nonpharmacologic and pharmacologic interventions.
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First, treat the underlying cause: start antibiotics for UTI (e.g., ceftriaxone or based on culture), optimize pain control (use non-opioid analgesics, reduce opioid dose if possible), ensure hydration, and monitor electrolytes. Nonpharmacologic measures: reorientation, involvement of family, sleep hygiene, mobility, and avoiding restraints. Use of a sitter may be necessary. Pharmacologic: antipsychotics are not FDA-approved for delirium but are used for severe agitation that poses danger. Use low-dose haloperidol (0.5-1 mg) or atypical antipsychotic like quetiapine (12.5-25 mg) if needed, with caution due to increased mortality risk in dementia. Avoid benzodiazepines unless alcohol withdrawal. Monitor for QT prolongation and extrapyramidal symptoms. Continue donepezil if possible (crushed or via NG if needed). Reassess frequently. Delirium often resolves with treatment of the underlying cause.