Use of VIrtual REAlity to Reduce Postoperative Anxiety and Pain After Surgery for Colorectal Cancer

The investigators plan to execute a randomized controlled, single-center, open-label, superiority interventional trial. Patients will be randomized into 2 parallel arms: 1 interventional "virtual immersion" arm and 1 "control" arm.

Randomization (1:1) will be stratified by cancer type (colon vs rectum). The randomization list will be balanced by small blocks of different sizes, randomly alternated to make it unpredictable. The block sizes will be provided in the final study report. The randomization list will be created by a member of the Digestive and Oncological Surgery department not involved in the study and will be added in REDCap software.

Study process:

• Preoperative consultation: information, surgery planning, obtaining patient consent, randomization and provision of 2 self-administered questionnaires: State-Trait Anxiety Inventory (STAI A "state" anxiety - French version) and CES-D (Center for Epidemiologic Studies - Depression - French version) to be completed at home.

Note: measures of depression (CES-D, Center for Epidemiologic Studies - Depression - French version) and alcohol and tobacco consumption are included. These are indeed confounding factors of anxiety and potential moderating factors of virtual reality's effectiveness.

• Beginning of the study (7 days before surgery): all patients filled in the self-questionnaires at home and brought them the day of the surgery.

• For the interventional arm, patients receive care according to the usual practices of the department as well as virtual reality. Virtual reality immersion offers a visual and auditory experience during a soothing journey through visual worlds filmed in natural environments. Virtual reality headset is put on the day before the operation and in the morning just before going to the operating theatre (only on the morning of the operation for patients hospitalized the same day). The colorectal cancer surgery then proceeds as usual. In the postoperative period, virtual reality sessions are offered every day and on request without any limit in number (day and night). Virtual reality sessions take place in the patient's room in bed or in the armchair on a fixed point, with a maximum duration of 30 minutes. The patient can stop the session at any time. The masks are cleaned before and after each use (Anios® wipes) and brought to the patient by the medical or paramedical staff (nurses only). Virtual reality sessions are prescribed by the medical staff using the software used in the department (Dxcare®). For each session, nurses record the duration of the session, the level of anxiety before the session (numerical scale with a score between 0 and 10), the reasons for a potential refusal, the tolerance and any comments on the programs used.

• For the control arm: patients are treated according to usual practices of the department and do not have access to virtual reality.

• End of study: at the end of the hospitalization, the patients fill in the same self-questionnaire State-Trait Anxiety Inventory (STAI A anxiety "state" - French version). In case of prolonged hospitalization for any reason, the end date of study, with the completion of the questionnaire, is set to the 30th postoperative day.

• No specific post-interventional follow-up is required for this research. The patients included in this study will continue their usual follow-up according to their initial condition and the department's procedures.

The main purpose is to show a greater decrease in anxiety in the interventional group by measuring the absolute difference between the State-Trait Anxiety Inventory scores before surgery and at discharge.

Sample size calculation:

• Control group: decrease of 2.55 points (STAI after-STAI before).

• Intervention group: decrease of 3.1875 points (STAI after-STAI before).

• With a relative difference of 25% (i.e. a difference of 0.6375 +/- 1.2) between the two groups, for an alpha risk of 5% and a power of 80%, 57 patients per arm are required, i.e. a total of 114 patients. To overcome the missing data risk, a 10% addition of patients was estimated, i.e. 124 patients in total.

The main analysis will be an intention-to-treat and per-protocol method. The primary endpoint will be compared between groups by linear regression adjusted for stratification factor and the STAI score at D-7. The application conditions will be checked by studying the residuals. No interim analysis is planned.