BACKGROUND: Delirium is underinvestigated in the neuro-critically ill, although the harmful effect of delirium is well established in patients in medical and surgical intensive care units (ICU).To detect delirium, a valid tool is needed. We hypothesized that delirium screening would be feasible in patients with acute brain injury and we aimed to validate and compare the Confusion Assessment Method for the ICU and the Intensive Care Delirium Screening Checklist against clinical International Classification of Diseases-10 criteria as reference.

METHODS: Nurses assessed delirium using the Confusion Assessment Method for the ICU and Intensive Care Delirium Screening Checklist in adult patients with acute brain injury admitted to the Neurointensive care unit (Neuro-ICU), Copenhagen University Hospital, if their Richmond agitation-sedation scale score was -2 or above. As the reference, a team of psychiatrist assessed patients using the International Classification of Diseases-10 criteria.

RESULTS: We enrolled 74 patients, of whom 25 (34%) were deemed unable to assess by the psychiatrists, leaving 49 (66%) for final analysis. Sensitivity and specificity for the Confusion Assessment Method for the ICU was 59% (95% CI: 41-75) and 56% (95% CI: 32-78), respectively, and 85% (95% CI: 70-94) and 75% (95% CI: 51-92), respectively, for the Intensive Care Delirium Screening Checklist.

CONCLUSIONS: Our findings suggest that the Intensive Care Delirium Screening Checklist may be a valid tool and the Confusion Assessment Method for the ICU is less suitable for delirium detection for patients in the Neuro-ICU. In the neuro-critically ill, delirium screening is challenged by limited feasibility.