An 82-year-old woman is evaluated for confusion and hallucinations while hospitalized. The patient was brought to the hospital by her daughter 2 days ago after she slipped and fell at home while walking up the stairs. She was found to have a left hip fracture and underwent open reduction with internal fixation with no complications. The patient's postoperative pain has been well controlled; however, she has been increasingly anxious and irritable since the day after the surgery. Today, the patient has difficulty attending to conversations with staff. She appears disoriented and distracted by visual hallucinations. The patient has a long-standing history of hypertension, insomnia, anxiety, and mild cognitive impairment. She has no history of alcohol or illicit substance use. Her daughter is unsure of the patient's home medications. The patient is afebrile, blood pressure is 160/98 mm Hg, pulse is 106/min, and respirations are 18/min. Pulse oximetry is 94%. She is tremulous, but the examination is otherwise nonfocal; the surgical wound appears to be healing well. Which of the following is the most likely cause of this patient's new symptoms?

Question

An 82-year-old woman is evaluated for confusion and hallucinations while hospitalized.  The patient was brought to the hospital by her daughter 2 days ago after she slipped and fell at home while walking up the stairs.  She was found to have a left hip fracture and underwent open reduction with internal fixation with no complications.  The patient's postoperative pain has been well controlled; however, she has been increasingly anxious and irritable since the day after the surgery.  Today, the patient has difficulty attending to conversations with staff.  She appears disoriented and distracted by visual hallucinations.  The patient has a long-standing history of hypertension, insomnia, anxiety, and mild cognitive impairment.  She has no history of alcohol or illicit substance use.  Her daughter is unsure of the patient's home medications.  The patient is afebrile, blood pressure is 160/98 mm Hg, pulse is 106/min, and respirations are 18/min.  Pulse oximetry is 94%.  She is tremulous, but the examination is otherwise nonfocal; the surgical wound appears to be healing well.  Which of the following is the most likely cause of this patient's new symptoms?

Quizplus · Accepted Answer

This patient's worsening agitation, impaired attention, and disorientation following surgery are suggestive of delirium. A number of etiologies are possible, including postoperative delirium, medication effect, and infection. However, this patient's tremulousness, hallucinations, and elevated vital signs (eg, hypertension, tachycardia) in the context of a psychiatric history consistent with a prescription of benzodiazepines (eg, anxiety, insomnia) are suggestive of delirium due to benzodiazepine withdrawal. Withdrawal can occur if a patient who has a history of prolonged use of benzodiazepines does not receive continued medication therapy on admission to the hospital. In severe cases, benzodiazepine withdrawal can result in seizures. Benzodiazepines, like alcohol, exert their inhibitory effects via GABA receptors, and their sudden withdrawal leads to an excitatory state. Sudden discontinuation can lead to withdrawal symptoms within 24-48 hours; withdrawal symptoms from long-acting benzodiazepines may develop over a more protracted period. Treatment of withdrawal includes reinitiation of benzodiazepines (usually a long-acting agent) that can then be gradually tapered down over weeks to months (and discontinued if necessary). (Choice B) Brief psychotic disorder is characterized by the presence of psychotic symptoms (eg, hallucinations, delusions) for >1 day but <1 month. This disorder cannot be diagnosed when the symptoms are better explained by another psychiatric disorder, general medical condition, or substance intoxication/withdrawal. (Choice C) This patient has a history of mild cognitive impairment, which may include some memory loss. Although she may be at risk for developing dementia, this would not present with acute onset of agitation and delirium. (Choice D) Opioids may be used for postoperative pain. However, this patient does not exhibit symptoms of opioid intoxication such as slurred speech, sedation, or respiratory depression. (Choice E) Although infection (eg, pneumonia) may also precipitate delirium, the patient is afebrile and has no localized symptoms or findings on physical examination (eg, no crackles on lung examination) that would indicate a localized infection. In addition, benzodiazepine withdrawal is more likely to explain her hypertension, tachycardia, hallucinations, and tremulousness. (Choice F) Although this patient's history of hypertension and recent surgery may place her at an increased risk for stroke, she does not have any localizing neurological findings on physical examination, making stroke unlikely. Her presentation is more consistent with benzodiazepine withdrawal. Educational objective: Benzodiazepine withdrawal may be characterized by agitation, tremors, perceptual changes, psychosis, elevated vital signs, delirium, and seizures. References: Sedative-hypnotic drug withdrawal syndrome: recognition and treatment. (http://www.ncbi.nlm.nih.gov/pubmed/28186869)

An 82-Year-Old Woman Is Evaluated for Confusion and Hallucinations While