Delirium Viva

Long Case Viva Defence

Candidate's opening statement (model answer)

"Mrs Margaret Chen is an 84-year-old retired nurse presenting with an acute confusional state on day 4 following a cemented hemiarthroplasty for a displaced femoral neck fracture sustained in a fall at home. She has a three-year history of mild-to-moderate Alzheimer disease, with a baseline MoCA of 18 out of 30 six months ago, and was previously functionally independent, living with her husband. [1]

Her past history also includes hypertension and osteoarthritis, and she has overactive bladder. [1]

Her medications are donepezil 10 mg daily, ramipril 5 mg daily, oxybutynin 5 mg twice daily, paracetamol regularly, and codeine as needed for pain. [1]

On the evening of day 4 she became acutely agitated, pulling at her intravenous cannula, calling out for her mother, and trying to climb out of bed. The CAM is positive. She is afebrile with stable observations. [1]

Her main problems are:

1. Acute postoperative delirium superimposed on Alzheimer dementia
2. High anticholinergic drug burden — oxybutynin directly opposing the donepezil she takes for her dementia
3. The recent hip fracture and hemiarthroplasty, with pain control and mobilisation to address
4. Risk of falls, pressure injury, and prolonged hospital stay
5. Family distress and need for education and involvement [1]

My integrated plan is to run a structured precipitant search using the DELIRIUM mnemonic — I have stopped the oxybutynin and minimised the codeine, I am checking for infection, dehydration, electrolyte disturbance, urinary retention, and constipation, and I have ordered a full septic screen and metabolic panel. I will institute multicomponent non-pharmacological care based on the HELP principles — orientation, environment, sensory aids, mobility, sleep protection, and family involvement. I will avoid benzodiazepines, and reserve low-dose haloperidol only for severe distress or danger, with the lowest effective dose and ECG monitoring, stopping as soon as possible. I will not stop the donepezil. I will explain the delirium to her husband, encourage his presence, and plan a cognitive reassessment after the delirium resolves." [1]

Examiner probing questions and model answers

Q1: "You mentioned stopping the oxybutynin but keeping the donepezil. Explain the pharmacological reasoning." [1]

"The reasoning rests on the cholinergic deficiency hypothesis of delirium. Acetylcholine is the neurotransmitter critical for attention, arousal, and cortical processing — the domains impaired in delirium. Donepezil is a cholinesterase inhibitor that increases acetylcholine and is protective against cognitive decline and, mechanistically, against delirium — I would never stop it in a patient on it for Alzheimer disease, because abrupt withdrawal can precipitate cognitive deterioration. Oxybutynin, in contrast, is a potent antimuscarinic anticholinergic — it directly blocks acetylcholine at muscarinic receptors and opposes the very mechanism the donepezil is supporting. It is among the highest anticholinergic-burden drugs in common use and is a well-established precipitant of delirium, especially in older adults with reduced cholinergic reserve. The combination of donepezil and oxybutynin is pharmacologically irrational — one increases acetylcholine, the other blocks it — and the net effect in this patient is cholinergic deficit contributing to her delirium. So I stop the oxybutynin immediately and keep the donepezil. For her overactive bladder, I would consider mirabegron, a beta-3 adrenergic agonist that relaxes the detrusor without anticholinergic activity, or a timed-voiding regimen, or, if an antimuscarinic is genuinely necessary, tolterodine or solifenacin have a lower anticholinergic burden than oxybutynin but still carry some risk. The principle is to minimise total anticholinergic burden in any older patient, and especially in one with dementia and delirium." [1]

Q2: "The nurses ask you to prescribe something to settle her because she is disturbing the ward. How do you respond?" [1]

"I would resist pressure to prescribe sedation reflexively. My response to the nursing staff is that sedation does not treat the delirium and may prolong it, and that our first priority is the cause search and the non-pharmacological measures. I would ask whether there is a reversible contributor we have not addressed — is she in pain, is she constipated, is she retaining urine, is she hungry or thirsty, is she frightened, has she had her glasses and hearing aids, is the environment contributing? I would ask whether a family member or a familiar aged-care volunteer could sit with her. I would consider one-to-one nursing if she is at risk of falling or removing her surgical drain. Only if her agitation poses a genuine risk of injury to herself or to her surgical repair, and the non-pharmacological measures and the cause treatment have been exhausted, would I consider a single low dose of haloperidol — 0.5 milligrams orally, or intramuscularly if she will not take oral, repeated after 2 to 4 hours if needed, with ECG monitoring for QT prolongation, and stopped as soon as possible. I would explicitly avoid a benzodiazepine — she is not in alcohol or benzodiazepine withdrawal, and benzodiazepines worsen and prolong delirium. I would document the indication, the dose, the monitoring, and the plan to stop, and I would explain the reasoning to the nurses so that we share the same conservative approach." [1]

Q3: "How would you distinguish her current state from progression of her Alzheimer disease?" [1]

"The distinction rests on the temporal pattern and the cognitive domains affected. Alzheimer disease is chronic, insidious, and gradually progressive over months to years, with a stable — though slowly declining — day-to-day course, relatively preserved attention in the early and moderate stages, and a normal level of consciousness until late. Her baseline MoCA of 18 out of 30 six months ago reflects her moderate Alzheimer disease, and her husband reports she had been functioning at that level until this admission. The current picture is an acute change over hours — her husband says she has been 'completely different since this morning' — with fluctuation, inattention on formal testing (she cannot recite the months of the year backwards), disorganised and rambling thinking, and altered behaviour. This acute, fluctuating disturbance of attention and awareness is delirium, not dementia. The key clinical rule is that dementia does not change over hours. An acute deterioration in a patient with known dementia is delirium superimposed on dementia until proven otherwise, and must be investigated and treated as delirium. I would document the baseline from the husband, plan a repeat MoCA after the delirium resolves to check for any step-down in her cognitive baseline — because the Witlox meta-analysis (PMID 20664045) established that delirium accelerates cognitive decline in patients with established dementia — and I would communicate the distinction to the family so they understand that this is a potentially reversible acute deterioration, not an inevitable progression of her dementia." [1]

Q4: "She had a fall at home before admission. Does that change your approach to the delirium workup?" [1]

"Yes, it does, because a fall in an older anticoagulated — or in her case, non-anticoagulated but aspirin-naive at presentation — patient raises the question of a head injury and an intracranial bleed, particularly a subdural haematoma, which can present with acute confusion days to weeks after the injury. I would ask the husband and the patient specifically whether she hit her head, whether there was loss of consciousness, whether she has had headaches, and whether there was any focal weakness or new neurological symptoms. I would examine her for focal neurological signs, papilloedema, and any scalp haematoma. If there is a history of head impact, or if she is anticoagulated or on antiplatelet therapy, or if focal signs emerge, or if the delirium does not begin to resolve with treatment of the identified precipitants over 48 to 72 hours, I would arrange a non-contrast CT brain to exclude a subdural haematoma, an intracerebral haemorrhage, or an infarct. In this patient, she is not on anticoagulants, and the most probable explanation for her delirium is the postoperative state with the anticholinergic drugs — but I would keep the subdural in the differential, particularly if the course is atypical or prolonged. She is not on aspirin currently for this admission, but I would check whether she was taking it before admission as part of her cardiovascular risk management, because even antiplatelet therapy increases the subdural risk." [1]

Q5: "What is the role of the Hospital Elder Life Program, and can it help a patient who already has delirium?" [1]

"The Hospital Elder Life Program, or HELP, developed by Inouye and validated in the landmark 1999 New England Journal trial (PMID 10688647), is the evidence-based multicomponent prevention programme that targets six modifiable risk factors for delirium during hospitalisation — cognitive impairment, sleep deprivation, immobility, visual impairment, hearing impairment, and dehydration — using trained volunteers supervised by an elder life nurse specialist. In the original trial it reduced delirium incidence from 15 percent to 9.9 percent. Its primary role is prevention, in at-risk older inpatients, before delirium develops. However, the same principles apply to a patient who already has delirium — the multicomponent interventions are not only preventive but also part of the management of established delirium. For Mrs Chen, I would apply every HELP component: reorientation and a therapeutic environment (clock, calendar, familiar objects, window view, minimised ward moves, appropriately lit room), sleep protection (clustered overnight nursing tasks, reduced noise), early and frequent mobilisation with the physiotherapist, her glasses and hearing aids at all times, and active hydration and nutrition support. The difference between prevention and treatment in this patient is that she already has the delirium, so I am also running the cause search and treating the precipitants in parallel — but the non-pharmacological supportive care is identical and is the mainstay of her management. The principle generalises to every ward: every older inpatient should have their orientation, hydration, sleep, mobility, vision and hearing actively addressed every day, because these are delirium prevention and delirium treatment." [1]

DCE Short-Case Viva — Cognitive Assessment

Examiner instruction: "This 82-year-old woman on the general medical ward is said to be confused. Please assess her cognition." [1]

Candidate's examination routine (narrated)

"I would begin by confirming the patient's identity, introducing myself, explaining what I am going to do, and ensuring she is comfortable, not in pain, and that she has her glasses and hearing aids if she uses them — these are essential for a valid cognitive assessment and are often missing on the ward. I would also note the time of day, because delirium often fluctuates and is worse in the evening. [1]

First, I assess her level of consciousness and alertness. I observe whether she is alert, drowsy, hypervigilant, or fluctuating. This is the first domain of the 4AT and a key discriminator — an altered level of consciousness is a red flag for delirium. [1]

Next, I assess attention, the cardinal cognitive domain in delirium. I ask her to recite the months of the year backwards — December, November, October, September, and so on. I am watching for errors, losing the thread, perseveration, or inability to start. If she cannot do this, I would try serial sevens — 100 minus 7 is 93, minus 7 is 86 — or digit span backwards. Impaired attention is the hallmark of delirium and distinguishes it from dementia and depression. [1]

I then assess orientation — to time (day, date, month, year, season), to place (the hospital name, the floor, the city), and to person (her name and date of birth). I document each item individually. [1]

I assess registration and recall — I name three objects (an apple, a table, a penny), ask her to repeat them to confirm registration, and then ask her to recall them after I have completed the rest of the assessment, about 3 to 5 minutes later. [1]

I assess language — naming (a watch, a pencil, a complicated object like the clasp of a pen), repetition ('no ifs, ands, or buts'), comprehension (a three-step command: take this paper in your right hand, fold it in half, put it on the floor), and reading and writing a sentence. [1]

I assess executive function and visuospatial ability with the clock-drawing test — I ask her to draw a clock face, put in all the numbers, and set the hands to ten past eleven. This tests planning, organisation, spatial layout, and frontal-executive function, and is very sensitive to both delirium and dementia. [1]

I check mood and insight — I ask how her mood is, whether she feels low, and whether she is aware that her thinking is not as it should be. [1]

Finally, and critically, I note the need for a collateral history — I would ask the nursing staff or arrange to speak with a family member to establish the patient's baseline cognition and the onset and course of the current change. The collateral history is often the single most useful piece of information in distinguishing delirium from dementia. [1]

I would then perform a focused general and neurological examination to look for clues to the precipitant — signs of infection, dehydration, focal neurological signs, signs of thyroid disease, medication effects — and stand back to present my findings." [1]

Presentation template (model answer)

"I performed a cognitive assessment on this 82-year-old woman. Her level of consciousness is reduced — she is drowsy but rousable, and the nursing staff report that she fluctuated during the morning. Attention is markedly impaired — she could not recite the months of the year backwards and lost the thread after two months. She is disoriented to time — she thinks it is 1998 — and to place — she cannot name the hospital. Registration of three objects was intact, but recall at 3 minutes was zero. Language shows some word-finding difficulty and her speech is rambling and disorganised. Her clock-drawing shows perseveration and disorganisation — the numbers are crowded on one side and the hands are misplaced. A collateral history from her daughter, obtained by telephone, confirms an acute change over the last 24 hours from a baseline of mild cognitive impairment, with fluctuation through the day. These findings meet the CAM criteria for delirium — acute onset and fluctuating course, inattention, and disorganised thinking — superimposed on her underlying mild cognitive impairment. I am now investigating the precipitant with a full septic screen, electrolytes, urinalysis, chest X-ray, ECG, and a medication review for anticholinergic burden, and I have instituted multicomponent non-pharmacological management." [1]

Examiner discussion

Q: "How does the 4AT differ from the CAM, and when would you use each?" [1]

"The CAM, or Confusion Assessment Method, developed by Inouye in 1990 (PMID 2240918), is a diagnostic instrument with four features — acute onset and fluctuating course, inattention, disorganised thinking, and altered level of consciousness — and a specific diagnostic rule requiring features 1 and 2 plus either 3 or 4. It has a sensitivity of 94 percent and specificity of 89 percent in trained hands, but it requires some training to administer reliably and it focuses on the syndrome of delirium rather than on broader cognitive function. The 4AT, validated by Shenkin and colleagues in 2014 (PMID 24590568), is a rapid 2-minute screening tool that scores alertness, the Abbreviated Mental Test-4 (age, date of birth, place, year), attention (months of the year backwards), and acute change or fluctuating course, with a score of 4 or more suggesting delirium. The 4AT is designed to be administered by any clinician without training and is increasingly used as a routine ward screening tool on admission and at 72 hours. I would use the 4AT for rapid screening of all at-risk older inpatients as part of routine care, and the CAM for a more formal diagnostic assessment when delirium is suspected — for example, on a geriatric or consultation-liaison psychiatry review. Both require a collateral history to establish the acute change and the baseline." [1]

Q: "How would the findings differ if this were depression rather than delirium?" [1]

"The key differences would be in the temporal pattern, the level of consciousness, and the attention. Depression develops over weeks to months, not hours, with a subacute onset and a stable — though often diurnally varying (worse in the morning) — course. The level of consciousness is normal — the patient is alert and not drowsy or fluctuating. Attention is relatively preserved — the patient can usually recite the months of the year backwards or do serial sevens, though they may be slow or give up easily (the classic 'I don't know' or 'I can't be bothered' answer pattern). Orientation is often correct. The mood is low, with anhedonia, hopelessness, and somatic complaints, and the history reveals a depressive illness. The cognitive impairment of severe depression — so-called pseudodementia — reverses with treatment of the depression. In contrast, this patient has acute onset over 24 hours, fluctuating reduced consciousness, markedly impaired attention, disorientation, and disorganised thinking — the pattern of delirium. The distinction matters because the management is entirely different: delirium requires a precipitant search and cause treatment, while depression requires psychiatric assessment and antidepressant therapy." [1]

Q: "What single bedside test most discriminates delirium from dementia?" [1]

"The single most discriminating feature is the acute onset with fluctuating course and impaired attention, which together form the core of delirium and distinguish it from the gradual, progressive, attention-preserving course of dementia. At the bedside, I would test attention formally by asking the patient to recite the months of the year backwards — a patient with mild-to-moderate dementia usually can do this, while a patient with delirium usually cannot, losing the thread or making errors. The fluctuation is established by collateral history and by serial observations — a patient who is lucid in the morning and confused at night has delirium until proven otherwise. The level of consciousness is also discriminating — it is altered (drowsy, hypervigilant) in delirium and normal in early-to-moderate dementia. None of these features is perfect in isolation, but together they reliably distinguish delirium from dementia in the great majority of cases. The caveat is that delirium frequently superimposes on dementia — an acute deterioration in a patient with known dementia is delirium until proven otherwise, and the acute change, the fluctuation, and the new inattention are the clues." [1]