Acute agitation after hip surgery in an older man
A 76-year-old retired teacher is admitted to the orthopedic ward after open reduction and internal fixation of a right hip fracture. On postoperative day 3 the nurses report that he is awake at night, pulling at his IV line, seeing 'men in the room,' and striking a nurse. He has hypertension, benign prostatic hyperplasia, and alcohol use of 4–5 beers daily until admission. Medications include oxycodone 5 mg every 6 hours, diphenhydramine 25 mg at night, ciprofloxacin, enalapril, and tamsulosin. Temperature 37.8°C, pulse 104, blood pressure 150/85, oxygen saturation 94% on room air. He is drowsy but fluctuates, with disorganized speech. Sodium is 124 mmol/L, potassium 4.1, creatinine 1.5 mg/dL (baseline 1.0), glucose 130 mg/dL. Urinalysis shows leukocytes and nitrites. Bladder scan shows 600 mL residual. The family asks why he is 'going mad' and whether he can sign a discharge form.
1. What is the most likely diagnosis, what alternatives must you exclude, and what immediate investigations and bedside actions do you prioritise?
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The leading diagnosis is delirium, probably multifactorial, superimposed on possible alcohol withdrawal and urinary retention. The key reasoning is acute onset, fluctuating attention, visual hallucinations, disorganized speech, and a postoperative medical milieu with several precipitants: infection, hyponatraemia, renal impairment, opioid and anticholinergic exposure, and alcohol withdrawal.
Alternatives to exclude include:
- Dementia: no documented premorbid decline, and the fluctuation is too acute.
- Alcohol withdrawal delirium: plausible, but usually appears 48–96 hours after the last drink and is accompanied by tremor, sweating, tachycardia and hypertension; it should be treated without missing the urinary and infective causes.
- Primary psychotic disorder or mania: less likely at this age with no prior history and clear medical triggers.
- Anticholinergic toxicity: diphenhydramine is a contributor; dry mouth, urinary retention and confusion fit.
- Hypoactive delirium mistaken for depression.
Immediate priorities are ABC, capillary glucose, repeat electrolytes and osmolality, urinalysis and urine culture, blood cultures, chest radiograph, ECG for QTc, bladder scan, pain assessment, and a careful medication review. Do not rely on the sodium value alone: check whether hyponatraemia is acute or chronic, assess volume status, and look for seizures or reduced consciousness. Treat the urinary retention, review antibiotics, stop diphenhydramine, and use the lowest effective opioid dose. A bedside collateral history from family about baseline cognition and alcohol intake is essential. Capacity should not be judged during delirium; it must be reassessed after the underlying cause is treated.
2. Outline your medication and environmental management, including correction of sodium and choice of any antipsychotic.
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Management should combine cause-directed treatment, non-drug measures and cautious symptomatic medication.
Sodium: at 124 mmol/L, correct slowly unless there are severe neurological signs such as seizures or coma. In chronic hyponatraemia, aim for no more than about 8–10 mmol/L rise in 24 hours to avoid osmotic demyelination. If severe symptoms are present, hypertonic saline is used in a monitored setting; otherwise treat the cause, review fluids and drugs, and recheck sodium frequently. Do not 'chase' the number rapidly.
Infection and retention: treat the urinary tract infection according to local guidance, relieve the 600 mL retention, and review ciprofloxacin and other deliriogenic drugs. Stop diphenhydramine. If alcohol withdrawal is active, use a validated withdrawal scale, give thiamine before glucose, and use benzodiazepines only for withdrawal - not as a general sedative for delirium.
Antipsychotic: if agitation threatens safety or treatment, use low-dose haloperidol 0.5–1 mg orally or intramuscularly, with ECG monitoring and review of Parkinsonism risk. Quetiapine 12.5–25 mg is an alternative, especially if there is parkinsonism, but it is more sedating and anticholinergic. Avoid benzodiazepines for pure delirium, avoid physical restraint where possible, and use one-to-one nursing, orientation, daytime lighting, uninterrupted sleep, glasses and hearing aids, familiar faces, and early mobilisation. Antipsychotics are adjuncts for distress or danger, not treatment for the delirium itself.
3. How do you assess capacity to sign the discharge form, and how do you discuss this with the family?
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Capacity is decision-specific and should be assessed for the particular decision - here, signing a discharge form and leaving hospital. The four elements are whether he can understand the relevant information, retain it long enough to decide, use or weigh it, and communicate a choice. During delirium, attention and arousal fluctuate, so capacity may vary hour to hour. A single conversation is inadequate.
The practical answer is that he should not be asked to sign a legally significant discharge form while acutely delirious. He lacks a stable ability to weigh information, and a signature obtained now is vulnerable to challenge. Treat the delirium, reassess when he is alert and oriented, and document the assessment. If he remains incapacitated, identify the appropriate surrogate decision-maker under local law and act in his best interests. Do not simply accept a family member's signature as equivalent to the patient's own consent unless the legal framework allows it.
With the family, explain in plain language that this is a medical brain syndrome, not 'madness' or permanent dementia. Link it to infection, dehydration, pain medication and alcohol withdrawal. Say that it often improves when the causes are treated, but that older patients may take days or weeks. Warn about falls, aspiration and distress, and ask them to bring glasses, hearing aids and orientation cues. Explain that discharge planning will continue, but that he cannot make the decision independently until his confusion settles. Avoid blaming the family or using jargon such as 'encephalopathy' without explanation.