The aim of this study is to investigate the effect of a non-pharmacological intervention-the use of a virtual reality headset-on preoperative anxiety levels in patients. For this purpose, both psychometric instruments (STOA and APAIS questionnaires) and objective physiological and EEG parameters are used. Patients who do not receive any additional intervention will form the control group.

The study was designed as a prospective, randomized, controlled, interventional study at the University Hospital Bonn. Patients aged 18 years and older who are scheduled to undergo elective surgery and who have no visual, hearing, or language impairments will be included in the study.

The primary objective of the study is the reduction of preoperative anxiety. The hypothesis is that preoperative use of the VR headset reduces perioperative anxiety, stress, and pain.

The investigators are planning a prospective, randomized controlled study with the aim of reducing patients' preoperative anxiety through VR use and improving postoperative pain and anxiety levels. After obtaining informed consent, patients will be randomly assigned to either the control or the intervention group. Stratification will be performed based on the presence of relatives during the preoperative process (yes/no) to ensure an even distribution of this potential confounding factor.

Patient anxiety will be assessed using the State-Trait Operation Anxiety (STOA) and the Amsterdam Preoperative Anxiety and Information Scale (APAIS) questionnaires. Stress and pain will be measured using the Numeric Rating Scale (NRS) from 0 to 10. A baseline assessment of simulator sickness will be performed using the Simulator Sickness Questionnaire (SSQ), which evaluates three symptom groups: nausea, oculomotor discomfort, and disorientation.

Following the questionnaires, patients will undergo EEG monitoring using the BIS device (Bispectral Index Monitor). The BIS is a medical monitoring device widely used in anesthesiology to measure anesthesia depth based on EEG data. Different mental states are associated with specific EEG frequency bands (alpha, beta, gamma, delta, and theta), and EEG is a well-established method for evaluating emotions. Alpha waves are linked to increased relaxation and reduced sympathetic arousal, and enhancing alpha waves in neurofeedback therapy has been shown to reduce anxiety. Beta waves are often associated with motor tasks and cognitive processing, and studies have also shown that increased beta activity correlates with higher anxiety levels. Anxiety affects beta activity by shifting power from lower to higher frequencies. All this suggests that a decrease in alpha-beta ratios (ABR) and low-high beta ratios (BR) may indicate the presence of stress and anxiety. EEG monitoring will continue until the first postoperative hour. Continuous EEG recording allows intraoperative and postoperative EEG patterns to be correlated with anxiety scores and postoperative pain.

During the preoperative process, all patients will be monitored for blood pressure, respiratory rate, oxygen saturation, and heart rate. These measurements will be used to objectively document the effects of sympathetic nervous system activation due to anxiety.

The control group will receive routine clinical care, while the intervention group will undergo a 20-minute VR session. During the session, patients will watch videos of natural landscapes and listen to calming music and nature sounds through headphones to promote relaxation. If any discomfort occurs, the session will be immediately stopped. At the end of the VR session, the SSQ will be repeated. Before entering the operating room, anxiety, stress, and pain levels will be assessed again.

During the first postoperative hour, anxiety, stress, pain, and patient satisfaction with the study procedure will be evaluated. Satisfaction with the study and the VR intervention will be measured using the NRS and a satisfaction questionnaire specific to the VR session. Patients will also be assessed for delirium using the Nursing Delirium Screening Scale (Nu-DESC). Throughout the entire process, all patients will be continuously monitored using EEG/BIS.

Inclusion Criteria:

• Age ≥ 18 years
• Written informed consent
• All consecutive patients undergoing elective, outpatient, or inpatient surgery
• No communication difficulties (e.g., hearing impairment) and good command of the German language
• No visual impairment
• Planned extubation immediately after surgery

Exclusion Criteria:

• Patients undergoing emergency surgery
• Patients with documented psychiatric disorders (e.g., bipolar disorder), confusion, or epilepsy
• Individuals admitted due to a court or official order
• Expected non-compliance with the study protocol
• Expected admission to an intermediate care unit (IMC) or intensive care unit (ICU)
• Patients receiving sedative or anxiolytic medication for premedication
• Patients with pacemakers or defibrillators