A patient with moderate Alzheimer disease can look at you, hold your question and give you a confident wrong answer. A delirious patient cannot hold the question long enough to be wrong. Inattention is the hallmark. Build a Confusion Assessment Method from real features, set the five axes and watch the three D’s separate, then run the cause hunt — and see exactly what sedating first would have cost this patient.
Feature 1 · Acute onset with a fluctuating course
Feature 2 · Inattention
Feature 3 · Disorganised thinking
Feature 4 · Altered level of consciousness
Motor subtype you are seeing
The rule. Delirium is present when features 1 and 2 are present, plus either 3 or 4.
Onset
Course
Attention (months backwards)
Level of consciousness
What the patient says about memory
Remember. All three coexist. Delirium is superimposed on dementia in a large share of hospitalised patients, and depression is common in both. The clinical question is never which one — it is what has changed acutely.
Your first-pass hunt — tick what you will actually do now
DELIRIUM.Drugs · Electrolytes · Lack of drugs (withdrawal, untreated pain) · Infection · Reduced sensory input · Intracranial · Urinary and faecal retention · Myocardial and pulmonary.
—Confusion Assessment MethodTick the features you can actually document.
The arithmetic
Subtype
How common, and why it mattersDelirium occurs in roughly 20 to 30 percent of hospitalised older medical patients, in more than half of patients after hip fracture repair, and in the majority of ventilated intensive-care patients. It is associated with longer stays, higher mortality, new nursing-home placement and lasting cognitive decline. Preventing and treating it is not a comfort measure — it is life-saving care.
?Which D?Set the five axes on the left.
Delirium0%
Dementia0%
Depression0%
Read the patternAttention and onset carry the most weight. Acute inattention with a fluctuating course is delirium until proved otherwise, no matter what else is on the list.
First nursing action—
Feature
Delirium
Dementia
Depression
Onset
Hours–days
Months–years
Weeks–months
Attention
Impaired
Normal until late
Intact
Consciousness
Altered
Normal
Normal
Reversibility
Usually, if the cause is found
Not reversible
Highly treatable
0First-pass coverageTick the actions you will take now.
What your choices meanThe first-pass workup for delirium is fast and mostly at the bedside. Choose, and each item will explain itself.
Stop — this one causes harm
Then treat without sedatingCause-directed care plus a non-pharmacological bundle prevents roughly a third of cases. Reorient at every contact with a visible clock, calendar and whiteboard. Glasses on the face, hearing aids in with working batteries, dentures in. Mobilise early and often. Remove tethers — unnecessary catheters, telemetry, continuous oximetry, lines, restraints. Protect sleep: light by day, dark and quiet at night, vital signs clustered so nobody is woken at 0200 for a blood pressure that could wait. Treat pain adequately — undertreated pain causes far more delirium than scheduled analgesia does. Bring family in; a familiar voice is a therapeutic intervention.