Mapping Randomized Controlled Trials of Early Mobilization Interventions for ICU Delirium: A Scoping Review

Background. Intensive Care Unit (ICU) delirium is a frequent manifestation of acute brain dysfunction among critically ill adults and is associated with prolonged hospitalization, increased mortality, institutionalization, long-term cognitive impairment, and functional decline. Early mobilization is included in contemporary ICU care bundles; however, the randomized trial literature remains heterogeneous in how mobilization is defined, implemented, and reported, and in how delirium outcomes are measured.

Objective. The study aimed to map and characterize randomized controlled trials (RCTs) evaluating early mobilization interventions for ICU delirium, focusing on intervention components, implementation and progression features, eligibility criteria, safety parameters, and delirium outcome reporting.

Methods. This scoping review was conducted in accordance with the Joanna Briggs Institute (JBI) Manual for Evidence Synthesis (Chapter on scoping reviews) and is reported following PRISMA-ScR. PubMed and CINAHL were searched from January 2009 to April 2024. We included RCTs enrolling adults in ICUs who received an early mobilization intervention during ICU stay and reported delirium incidence and/or duration measured using validated tools. Two reviewers independently screened records and charted data using a structured extraction form. Findings were synthesized descriptively.

Results. Six (6) RCTs (n = 859) met the inclusion criteria, enrolling predominantly middle-aged to older adult ICU populations (mean/median ages approximately 55–75 years), reflecting the higher delirium risk profile in this demographic. Interventions ranged from passive range-of-motion and bed mobility to sitting, standing, pre-ambulation, ambulation, cycling, progressive resistance exercise, and basic activities of daily living. Across trials, patient selection, physiological stability thresholds, session frequency/duration, progression rules, and termination criteria varied. Delirium was commonly assessed using the Confusion Assessment Method for the ICU (CAM-ICU), but outcomes were reported using non-uniform metrics (e.g., delirium incidence, delirium days, percentage time delirious, delirium-free days).

Conclusion. The RCT literature on early mobilization for ICU delirium demonstrates substantial heterogeneity in intervention design, eligibility and safety criteria, and outcome reporting. This mapping clarifies the structure of randomized evidence and highlights priorities for standardizing intervention descriptions, safety reporting, and delirium outcome metrics to support future synthesis and implementation research.