Anaesthesia / Critical Care Emergency Medicine General Medicine Strong — Crit Care Med 2001

Confusion Assessment Method for ICU (CAM-ICU)

Validated delirium assessment for ICU patients. CAM-ICU is POSITIVE if Feature 1 AND Feature 2 are present, PLUS Feature 3 OR Feature 4. Only assess if RASS ≥ −3 (not deeply sedated).

Used in: Delirium & Cognitive Impairment

Feature 1: Acute Onset or Fluctuating Course*

Is there an acute change in mental status from baseline? OR did it fluctuate (better/worse) in the past 24 hours?

Feature 2: Inattention*

Did the patient have difficulty focusing attention? Use Attention Screening Exam (ASE): ask patient to squeeze hand only when you say 'A' — read SAVEAHAART. Score <8/10 = inattention present.

Feature 3: Altered Level of Consciousness*

Is the current RASS score anything other than 0 (alert and calm)?

Feature 4: Disorganised Thinking*

Does the patient have disorganised or incoherent thinking? Rambling conversation, illogical flow of ideas, unpredictable topic switching, or incoherent responses to simple questions (e.g. Does a stone float on water? Are there fish in the sea?)

Score interpretation

CAM-ICU Negative — No Delirium 0–1

Score 0–1: CAM-ICU Negative. Delirium absent.

→ Continue monitoring. Reassess every nursing shift. Implement non-pharmacological prevention: early mobilisation, sleep hygiene, reorientation, reinstate hearing aids and glasses.

Indeterminate — Clarify Which Features Are Positive 2

Score 2: Ambiguous. If Feature 1 AND Feature 2 are both positive but Feature 3 and 4 are absent → CAM-ICU Negative. If only Features 3+4 positive (without F1 and F2) → also Negative. Re-examine carefully.

→ Reassess all four features systematically. Remember: CAM-ICU is POSITIVE only if Feature 1 AND Feature 2 are present, PLUS Feature 3 OR Feature 4. Document the specific positive features.

CAM-ICU Positive — Delirium 3–4

Score 3–4: CAM-ICU Positive (confirm Feature 1 AND Feature 2 are among positives). Delirium present.

→ Use THINK mnemonic — Toxic medications (anticholinergics, opioids, BZDs), Hypoxia, Infection/Inflammation, Non-pharmacological measures, K+ (electrolytes). Non-pharmacological interventions first-line. Haloperidol or quetiapine for severe hyperactive delirium. Avoid benzodiazepines. Notify medical team. Safety measures (low bed, call bell, sitter if needed).

Interpretation bands for the CAM-ICU. Apply clinical judgement and local guidance.

References

Ely EW et al. Evaluation of delirium in critically ill patients: validation of the CAM-ICU. Crit Care Med. 2001;29(7):1370–1379.
Devlin JW et al. PADIS Clinical Practice Guidelines. Crit Care Med. 2018.

Curated clinical cross-links plus same-class fallbacks.

Calculators

PICU Delirium Assessment (pCAM-ICU) · Delirium Assessment

Drugs

Pathways

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.

Score interpretation

References

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