Standardized Measures > CAM-ICU & bCAM
The CAM-ICU is a validated bedside delirium screening tool adapted for the ICU, including patients who are intubated or otherwise unable to speak. It can be administered by any bedside provider and takes under two minutes. A positive screen is not a reason to cancel your session — delirium is an OT treatment target. It's a reason to modify your approach.
Before administering, check the patient's RASS score. If the RASS is −4 or −5 (deep sedation or unarousable), the CAM-ICU cannot be validly administered. Return when the patient is more aroused.
Two types of delirium — both screen positive
Hyperactive delirium is what most clinicians picture: agitation, combativeness, attempts to remove lines. Hypoactive delirium is quieter and more commonly missed — the patient who is withdrawn, staring, slowed in speech and movement. Both are associated with worse outcomes and both can be addressed in OT sessions. Hypoactive delirium is frequently mistaken for fatigue, depression, or appropriate sedation; the CAM-ICU catches it.
The Four Features
Delirium is CAM-ICU positive when Feature 1 AND Feature 2 are present, AND either Feature 3 OR Feature 4.
Feature 1: Acute onset or fluctuating course of mental status
Review RASS scores over the last 24 hours and compare to the patient's baseline. Any acute change or fluctuation — including fluctuation toward improvement — satisfies this feature.
Feature 2: Inattention
Ask the patient to squeeze your hand each time they hear the letter A in the sequence S-A-V-E-A-H-A-A-R-T. Count both errors of omission (no squeeze on A) and commission (squeeze on a non-A letter). More than 2 errors = inattention present. If the patient cannot perform this task, use the picture version from the training manual.
Feature 3: Altered level of consciousness
Record the current RASS score. Any score other than 0 (alert and calm) satisfies this feature.
Feature 4: Disorganized thinking
Four yes/no questions: Will a stone float on water? Are there fish in the sea? Does one pound weigh more than two pounds? Can you use a hammer to pound a nail? Plus one motor command: hold up this many fingers, now do the same with the other hand. More than 1 error = disorganized thinking present.
What a positive screen means for your session
A positive CAM-ICU tells you the patient's brain is not functioning clearly, and your session should be calibrated accordingly — shorter duration, simpler tasks, slow and clear language, reduced environmental stimulation. Reorientation, structured cognitive activity, and family involvement are all within OT scope for the delirious patient.
Communicate your findings to nursing and document them. Repeated positive screens across shifts build a picture that informs medication management, sleep protocols, and goals-of-care conversations.
Brief Confusion Assessment Method (bCAM)
(Han et al., 2013)
The bCAM is a modified CAM-ICU designed for non-critically ill patients — primarily the emergency department and hospital floor. It uses month-backward testing to assess inattention rather than the letter-squeeze task, and the patient must have inattention (Feature 2 positive) to screen positive. Features 1, 3, and 4 are identical to the CAM-ICU.
The CAM-ICU is preferred for ICU patients. Use the bCAM when assessing patients being stepped down to a general floor, or in floor-based settings where the bCAM is the standard tool.
References
Ely, E. W., Inouye, S. K., Bernard, G. R., Gordon, S., Francis, J., May, L., Truman, B., Speroff, T., Gautam, S., Margolin, R., Hart, R. P., & Dittus, R. (2001). Delirium in mechanically ventilated patients: Validity and reliability of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). JAMA, 286(21), 2703–2710. https://doi.org/10.1001/jama.286.21.2703
Ely, E. W. (2016). Confusion assessment method for the ICU (CAM-ICU): The complete training manual. Vanderbilt University Medical Center.
Han, J. H., Wilson, A., Vasilevskis, E. E., Shintani, A., Schnelle, J. F., Dittus, R. S., Graves, A. J., Storrow, A. B., Shuster, J., & Ely, E. W. (2013). Diagnosing delirium in older emergency department patients: Validity and reliability of the Delirium Triage Screen and the Brief Confusion Assessment Method. Annals of Emergency Medicine, 62(5), 457–465. https://doi.org/10.1016/j.annemergmed.2013.05.003
Ho Han, J. (2015). Brief confusion assessment method (bCAM) (pp. 1–11). https://uploads-ssl.webflow.com/5b0849daec50243a0a1e5e0c/5bb3783be59e3422910fc5ba_bCAM-Training-Manual-Version-1-0-10-15-2015.pdf