Abstract
BACKGROUND: Survivors of critical illness frequently experience persistent cognitive impairment. However, structured cognitive rehabilitation interventions remain limited within intensive care pathways. While physical rehabilitation has received increasing attention, evidence guiding cognitive rehabilitation in intensive care unit (ICU) populations is sparse, and the feasibility of study procedures must be established before large-scale evaluation. AIM: To assess the feasibility of conducting a multi-arm randomised controlled trial evaluating a cognitive rehabilitation intervention (ICU CogHab) for ICU survivors. STUDY DESIGN: A pragmatic, five-arm randomised feasibility study was conducted across four ICUs at two Danish university hospitals. Feasibility outcomes included screening and recruitment, randomisation procedures, retention through 6-month follow-up and completion of patient-reported and performance-based outcome measures. Data were analysed descriptively to summarise feasibility parameters and outcome variability. RESULTS: Of 1679 patients screened, 115 met eligibility criteria and 83 were randomised. Recruitment was lower than anticipated, and retention at 6 months was 40%. Clinical data obtained from medical records were largely complete, whereas cognitive and patient-reported outcomes were more difficult to complete at ICU discharge. Outcome measures demonstrated substantial variability. CONCLUSION: This study shows that screening and randomisation procedures for a cognitive rehabilitation intervention are feasible within routine ICU practice. Retention and data completeness, particularly after hospital discharge, represent key challenges requiring refinement before further evaluation. RELEVANCE TO CLINICAL PRACTICE: Cognitive rehabilitation can be introduced within routine ICU workflows. However, the timing of assessments, follow-up procedures and integration into clinical practice require optimisation. These findings inform pragmatic adaptations to support future evaluation and implementation of cognitive rehabilitation for ICU survivors. TRIAL REGISTRATION: The study was prospectively registered on the Open Science Framework (https://osf.io/b57fv/overview).