Confusion Assessment Method for the ICU (CAM-ICU)
Why Use
Delirium affects up to 89% of ICU patients and has been shown to result in higher mortality. The relative risk of death increases for each day the patient remains delirious. Prompt recognition of this condition is therefore important. To this day delirium remains a clinical diagnosis. Few clinical tools have been demonstrated to be useful in helping identify the presence or absence of delirium.
When to Use
The CAM-ICU should be used daily on all patients admitted to the ICU even if they are mechanically ventilated.
Formula
Pearls / Pitfalls
Delirium has been shown to be associated with worse outcomes in critically ill patients. It remains underdiagnosed given its sometimes subtle presentation. The CAM-ICU score is a validated and commonly used score to help monitor patients for the development or resolution of delirium. It is an adaptation of the Confusion Assessment Method (CAM) score for use in ICU patients. Since the first step of the score consists of identifying an “acute change from mental status baseline”, it may be difficult to use in patients in whom the neurologic baseline is unknown. If a patient’s neurologic baseline changes during the course of his hospitalization (such as a new CVA for example), then the new baseline should be used for any new assessment. In order for the CAM-ICU score to be accurate, patients should not be sedated, or have a RASS of 0.
Management
When applied, the CAM-ICU will provide a qualitative result of “delirium present” or “delirium absent”. Patients identified as suffering from delirium will be investigated and managed accordingly. The CAM-ICU should continue to be used daily even in patients that are delirious in order to monitor for resolution of the condition.
Critical Actions
The management of delirium is an extensive topic that is beyond the scope of this discussion. Screen all ICU patients daily for delirium using a validated clinical tool such as the CAM-ICU. The screening is best performed by individuals trained in the proper usage of this method such as ICU nurses.
More Information
The patient is CAM-ICU positive (patient has delirium) if: RASS ≥ -3, AND Acute onset change in mental status or fluctuating course in mental status, AND >2 errors in letters attention test, AND Either RASS is not 0, OR combined number of errors to questions and commands >1 For more information and a schematic of questions, see this CAM-ICU training manual .