Mike: Hello, I'm Mike Clarke, podcast editor for the Cochrane Library. Many patients in intensive care develop delirium and there are several Cochrane reviews of ways to treat it. In November 2023, we added a review on the reliability of the confusion assessment method for diagnosing it and asked lead author, Fabian Miranda from the Universidad de Chile in Santiago, to tell us about the topic and the review's findings in this podcast.

Fabian: Delirium is a clinical syndrome characterized by an acute alteration in a person's mental status. It's a major problem in intensive care units, or ICUs, because of its high prevalence, the significant discomfort it generates in patients, and its association with adverse outcomes. Diagnosing delirium is very challenging, especially in patients who are mechanically ventilated because they cannot participate in a verbal interview. In addition, a psychiatrist or similar specialist needs to confirm the diagnosis, and they are not always available.
The confusion assessment method for the ICU, or CAM-ICU for short, is an alternative. This instrument was specifically designed to assess delirium in ICU patients, including those on mechanical ventilation. It also has the advantage that it can be administered by medical and non-medical personnel after simple training, providing a simple result of present or absent delirium.
We investigated the diagnostic accuracy of the CAM-ICU in ICU patients and compared it with what is considered the reference standard, that is, an evaluation performed by a psychiatrist applying the diagnostic criteria of the DSM, which stands for Diagnostic and Statistical Manual of Disorders.
We identified 25 studies, with a total of just over 2800 participants for the review. Taken together, these show that the CAM-ICU correctly identified patients with delirium approximately three-quarters of the time. The test was better at identifying people without delirium and returned correct results about 95% of the time.
Stand-out features of the results are that the CAM-ICU was applied by non-medical personnel in some of the included studies, and similar results were observed both in patients with and without mechanical ventilation.
Therefore, given its easy availability and applicability, we can conclude that the CAM-ICU is a reasonable test to screen for delirium in critical care.

Mike: To find out more about the CAM-ICU and its accuracy for diagnosing delirium, go to Cochrane Library dot com and search 'CAM‐ICU and delirium' to see a link to it.