Delirium assessment in the critically ill

To compare available instruments for assessing delirium in critically ill adults that have undergone validity testing and provide clinicians with strategies to incorporate these instruments into clinical practice.

Medline (1966-September 2006) was searched using the key words: delirium, cognitive dysfunction, assessment, intensive care unit, and critical illness to identify assessment tools that have been used to evaluate delirium in critically ill adults. A special emphasis was placed on delirium assessment tools that have been properly validated. Data on how these tools have been adopted into clinical practice as well as strategies for clinicians to improve delirium assessment in the ICU are highlighted.

Six delirium assessment instruments including the Cognitive Test for Delirium (CTD), abbreviated CTD, Confusion Assessment Method-ICU, Intensive Care Delirium Screening Checklist, NEECHAM scale, and the Delirium Detection Score were identified. While each of these scales have undergone validation in critically ill adults, substantial differences exist among the scales in terms of the quality and extent of the validation effort, the specific components of the delirium syndrome each address, their ability to identify hypoactive delirium, their use in patients with a compromised level of consciousness, and their ease of use.

Incorporation of delirium assessment into clinical practice in the intensive care unit using a validated tool may improve patient care. Clinicians can adopt a number of different strategies to overcome the many barriers associated with routine delirium assessment in the ICU.