Virtual Reality-based Sensory Stimulation for Delirium Prevention in Intensive Care Units

Delirium is a common acute neurocognitive disorder in critically ill patients and is associated with poor short- and long-term outcomes, including prolonged ICU stay, extended mechanical ventilation, persistent cognitive impairment, and reduced quality of life after discharge. Environmental factors in the ICU, particularly sensory deprivation and excessive noise and light disturbance, are recognized as modifiable contributors to delirium risk.

Conventional sensory stimulation has shown potential to delay delirium onset and reduce delirium severity in ICU patients. However, implementation in routine ICU practice is challenging because intervention delivery may be disrupted by the complex ICU environment and may vary across clinical staff and settings.

This study evaluates a virtual reality (VR)-based sensory stimulation intervention designed to provide immersive visual and auditory input while reducing interference from the ICU environment. The intervention uses a head-mounted display and headphones to deliver standardized nature-based content. An active control condition was selected to receive the same content through a tablet, allowing comparison of immersive versus non-immersive delivery while controlling for the sensory content itself.

This study is a pilot randomized controlled trial conducted in adult ICU patients. Participants are randomly assigned in a 1:1 ratio to either the VR intervention group or the active control group. Both groups receive one 20-minute session daily for up to 3 days during ICU stay. Delirium is assessed twice daily during ICU stay, and participants are followed at 3 months after ICU discharge for cognitive and quality-of-life outcomes. The study is intended to generate preliminary estimates of intervention effects and to inform the design of a future definitive trial.

Inclusion criteria

• Age 18 years or older
• Admitted to the ICU
• Undergoing or expected to require mechanical ventilation
• Expected ICU stay of at least 48 hours
• Awake or lightly sedated, defined as a Richmond Agitation-Sedation Scale - (RASS) score between -1 and +1
• Able to understand and follow instructions
• Provided informed consent [or surrogate consent, if applicable]

Exclusion criteria

• Pre-existing cognitive impairment or dementia
• Acute psychiatric illness at admission
• Delirium at enrollment as assessed by CAM-ICU
• Terminal-stage cancer
• APACHE II score > 20
• Severe uncorrectable hearing or visual impairment
• Traumatic brain injury or intracranial drainage tubes that make use of the VR headset impractical