Weve discussed the importance of recognizing delirium in multiple columns (see the list at the end of todays column). Yet delirium goes unrecognized or undiagnosed in up to 72% of cases in hospitalized patients (Collins 2010). One of the reasons may be that commonly used screening tests for delirium may not be brief enough or may require specific training for administration.
So researchers have developed a new screening tool, the 4 As Test (4AT) to help improve screening for delirium.
The 4AT tool has now been validated in a population other than that in which it was developed (Bellelli 2014). The authors note that the many of the currently used screening tools for delirium lack some of the following characteristics:
Bellelli and colleagues therefore administered the 4AT in 236 consecutive elderly patients admitted to an acute geriatrics ward or a post-acute rehabilitation unit. The CAM (Confusion Assessment Method) was used as the reference diagnostic standard and the DSM-IV-TR criteria used for diagnosis. Delirium was detected in 12.3%, dementia in 31.2%, and a combination of both in 7.2%. The 4AT had a sensitivity of 89.7% and specificity 84.1% for delirium. Specificity was higher in the subgroup without dementia, while sensitivity was higher in the group with dementia. The authors conclude that the 4AT is a sensitive and specific method of screening for delirium in hospitalized older people and that its brevity and simplicity support its use in routine clinical practice.
We recommend that, if youve been using a validated tool like the CAM and have been using it regularly to screen for delirium, you continue to use it. But if you have not been regularly screening for delirium, consider giving the 4AT a try. Its simple and easy to administer and appears to be a reliable tool.
Some of our prior columns on delirium assessment and management:
· October 21, 2008 Preventing Delirium
· October 14, 2009 Managing Delirium
· February 10, 2009 Sedation in the ICU: The Dexmedetomidine Study
· March 31, 2009 Screening Patients for Risk of Delirium
· June 23, 2009 More on Delirium in the ICU
· January 26, 2010 Preventing Postoperative Delirium
· August 31, 2010
· September 2011 Modified HELP Helps Outcomes in Elderly Undergoing Abdominal Surgery
· December 2010 The ABCDE Bundle
· February 28, 2012 AACN Practice Alert on Delirium in Critical Care
· April 3, 2012 New Risk for Postoperative Delirium: Obstructive Sleep Apnea
· August 7, 2012 Cognition, Post-Op Delirium, and Post-Op Outcomes
· September 2013 Disappointing Results in Delirium
· October 29, 2013 PAD: The Pain, Agitation, and Delirium Care Bundle
· February 2014 New Studies on Delirium
· March 25, 2014 Melatonin and Delirium
· May 2014 New Delirium Severity Score
Collins N, Blanchard MR, Tookman A, Sampson EL. Detection of delirium in the acute hospital. Age Ageing 2010; 39 (1): 131-135
The 4 As Test: screening instrument for delirium and cognitive impairment
Bellelli G, Morandi A, Davis DHJ, et al. Validation of the 4AT, a new instrument for rapid delirium screening: a study in 234 hospitalised older people. Age Ageing 2014; 43(4): 496-502
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