Confusion Assessment Method (CAM)
This method of assessment was developed in the 1990′s and is the standard tool for screening for delirium in all patients. It has been slow to be adopted in EDs and as a result we miss a lot of episodes of delirium. Though there is good evidence from multiple studies that up to 10% of all older patients in EDs have a delirium, only about one-third of them are recognized.
These features are based on the AIDA Mnemonic and the DSM-IV definition of delirium:
A- Acute and fluctuating
D- Disorganized thinking: incoherent, rambling
A- Altered level of consciousness: drowsy, lethargic, stuporous, hyper-alert, agitated
Summary of Features
Click on a feature below to learn more.
This feature is usually obtained from a family member or nurse and is shown by positive responses to the following questions:
- Is there evidence of an acute change in mental status from the patient’s baseline?
- Did the (abnormal) behaviour fluctuate during the day, that is, tend to come and go, or increase and decrease in severity?
COLLATERAL HISTORY IS ESSENTIAL!
This feature is shown by a positive response to the following question:
Did the patient have difficulty focusing attention, for example, being easily distractible, or having difficulty keeping track of what was being said?
Can test with 5 item forward digit span; 3 item backward digit span; months of the years backwards; WORLD; serial 7s
This feature is shown by a positive response to the following question: Was the patient’s thinking disorganized or incoherent, such as rambling or irrelevant conversation, unclear or illogical flow of ideas, or unpredictable switching from subject to subject?
This feature is shown by any answer other than “alert” for the following question:
Overall, how would you rate the patient’s level of consciousness? (alert [normal], vigilant [hyperalert], lethargic [drowsy, easily aroused], stupor [difficult to arouse], or coma [unarousable]).
- Watch the video below and answer the following question.
- What components of the Confusion Assessment Method are illustrated here?