BackgroundFor people with cognitive impairment, hospitalisation is challenging and associated with adverse events as well as negative outcomes resulting in a prolonged hospital stay. Person-centred care can improve the quality of care and the experience of people with cognitive impairment during hospitalisation. However, current care processes in German hospitals are rarely person-centred. To enable successful implementation of person-centred care on hospital wards, change agents within the interprofessional team are key. The aim of this study is to test the feasibility and initial effects of a newly developed complex person-centred care intervention for people with cognitive impairment provided by expanded practice nurses in acute care.MethodsWe will conduct an exploratory non-randomised controlled clinical trial with accompanying process and cost evaluation with three intervention and three control wards at one university hospital. The person-centred care intervention consists of 14 components reflecting the activities of expanded practice nurses within the interprofessional team on the intervention wards. The intervention will be implemented over a six-month period and compared with optimised care on the control wards. We will include people aged 65 years and older with existing cognitive impairment and/or at risk of delirium. The estimated sample size is 720 participants. The primary outcome is length of hospital stay. Secondary outcomes include prevalence of delirium, prevalence of agitation, sleep quality, and person-centred care. We will collect patient level data at six time points (t1 admission, t2 day 3, t3 day 7, t4 day 14, t5 discharge, t6 30 days after discharge). For secondary outcomes at staff level, we will collect data before and after the intervention period. The process evaluation will examine degree and quality of implementation, mechanisms of change, and the context of the complex intervention. The economic evaluation will focus on costs from the hospital’s perspective.DiscussionThe ENROLE-acute study will provide insights into the effectiveness and underlying processes of a person-centred care intervention for people with cognitive impairment provided by expanded practice nurses on acute hospitals wards. Results may contribute to intervention refinement and evidence-based decision making.Trial registrationCurrent controlled trials: ISRCTN81391868. Date of registration: 12/06/2023. URL: https://doi.org/10.1186/ISRCTN81391868