Mapping the Evidence on Virtual Reality for Post-Intensive Care Syndrome: A Systematic Review and a Five-Axis VR-PICS Taxonomy

Background: Post-Intensive Care Syndrome (PICS), comprising physical, cognitive, and psychological impairments, affects 50–75% of Intensive Care Unit (ICU) survivors and leads to long-term deficits. Virtual Reality (VR) has emerged as a tool to reduce ICU-related stress and support recovery, yet evidence remains fragmented and heterogeneous. Objective: To systematically review the safety, feasibility, and effects of immersive VR interventions targeting PICS-related outcomes in ICU and post-ICU populations, and to introduce a standardized taxonomy to classify and compare VR interventions in critical care contexts. Methods: This systematic review followed PRISMA 2020 guidelines and was registered in PROSPERO (CRD420251174623). Seven databases (Cochrane Library, PubMed, ScienceDirect, IEEE Xplore, ACM Digital Library, SpringerLink, and Scopus) were searched from inception to 2 August 2025. Eligible studies included ICU patients receiving immersive VR via head-mounted displays and targeting at least one PICS domain. Two reviewers independently screened studies and extracted data. Methodological quality was assessed using the Mixed Methods Appraisal Tool (MMAT, 2018). Due to substantial heterogeneity, findings were synthesized narratively. Results: Eleven studies were included. The most consistent effects concerned acute psychological outcomes, with 63.6% of studies reporting reduced anxiety or distress. Evidence for physical, cognitive, or long-term outcomes was limited and inconsistent, largely due to small samples, non-randomized designs, and brief intervention dosing. Conclusion: Current evidence supports VR as a feasible adjunct for acute psychological support in ICU settings. However, meaningful rehabilitation effects remain underexplored. The Five-Axis VR-PICS taxonomy clarifies intervention heterogeneity and provides a structured framework to guide rehabilitation-oriented VR research in critical care.