Acceptability and Fidelity of a Cognitive Rehabilitation Intervention During and After Intensive Care: A Feasibility Evaluation

BACKGROUND: Cognitive impairment is common after critical illness, yet structured cognitive rehabilitation is rarely integrated into routine intensive care practice. ICU CogHab is a stakeholder- and theory-informed intervention comprising two components: Mindfulness and Brain Training, developed to support recovery from intensive care to 6-month follow-up. AIM: To evaluate the feasibility of the ICU CogHab intervention, focussing on acceptability and fidelity among ICU patients and nurses. STUDY DESIGN: A multi-method feasibility evaluation was conducted alongside a pragmatic, five-arm randomised controlled feasibility trial in four Danish ICUs. Data were collected using patient and nurse surveys and semi-structured interviews. Acceptability was explored in terms of three domains: affective attitude, burden and perceived effectiveness. Fidelity was assessed in relation to adherence and dose, with participant responsiveness and quality of delivery examined within adherence. Quantitative data were analysed descriptively, and qualitative data were analysed using deductive content analysis. RESULTS: Thirty-one patients contributed with survey data and nine participated in interviews. In addition, 53 nurses contributed with 194 session-based surveys and seven interviews, informing evaluation of delivery during ICU admission. Both components were generally perceived as relevant and appropriate by patients and nurses. Patients described the components as meaningful and supportive. Fidelity varied across settings and over time, with adherence and dose influenced by clinical condition, fatigue, patient readiness and competing rehabilitation demands, meaning that intervention use often required adaptation in timing and duration across recovery phases. Nurses reported contextual barriers to delivery, including high workload and competing clinical priorities. CONCLUSION: The ICU CogHab intervention components demonstrated overall acceptability across ICU and post-discharge phases. Variation in fidelity reflected the patient condition, clinical context and competing demands, providing direction for further refinement before larger-scale evaluation. RELEVANCE TO CLINICAL PRACTICE: Cognitive rehabilitation may be acceptable and feasible to introduce within intensive care pathways but delivery may require flexible timing, integration into routine care and support across the ICU-to-home transition.