Appendicitis is a common pathology and the one of the most common surgical procedures performed in France. Young subjects are the most frequent patients with appendicitis. Appendicular peritonitis increases post-operative pain, morbidity, and the average length of hospital stay compared to uncomplicated appendicitis.

Pain alters perioeprative rehabilitation of patients. Surgery, performed urgently, generates more anxiety and pain than scheduled surgery. But, intensity of chronic postoperative pain is in correlation to intensity of acute postoperative pain. In addition, admission of emergency cases is more axiety-inducing, due to wait times, packed emergency room, worklaod of medical staff.

Sex and age also modify perception of postoperative pain. Adults under 50 feel more pain than older patients for similar procedures.

Medication for pain is required in perioperative period et is administered according protocol of each medical center ; these protocols include analgesics, opioids or not, benzodiazepine... However, opioids analgesic (example: morphine) can induce side effect, such as confusional syndrome, cardio-pulmonary manifestations, ileus, nausea and vomiting...

Non-pharmacological approaches have been also proposed to reduce anxiety and pain. Hypnosis is frequently used but not always adapted to the emergency: need for qualified and available staff, environment not conducive to hypnotic induction...

Hypnosis is a modified state of consciousness ; it is neither a state of vigilance nor a state of sleep. Several types of hypnosis can be distinguished according to the medical application, such as hypnoanalgesia or hypnosedation.

Using hypnosedation during surgical or invasive procedure can reduce the use of painkillers and sedatives. Interest of hypnosis has been observed for extraction of wisdow teeth, delivery...

Young patients are very comfortable with the use of their smartphone which is often the first object recovered when they return from the operating room. Many hypnosis videos are available free of charge on Internet, and some of which are produced by specialized practitioners and university teachers.

A recent study has shown that among young people, addiction to smartphone is a predisposition to hypnosis.

However, the use of hypnosis videos on smartphone has never been studied for the control of postoperative pain.

Inclusion Criteria:

• Patients aged 18 years and over
• Complicated acute appendicitis with generalized appendicitis, coelioscopy emergency surgery
• Signature of the written informed consent form by the patient
• Affiliation to a French health insurance scheme or equivalent
• Patient inderstands French and has a smartphone with internet access

Non inclusion Criteria:

• Uncomplicated or complicated appendicitis of abscesses, presence of an intraperitoneal abscess, a plastron, uncomplicated appendicitis of generalized peritonitis
• Patient with a neurological, visual or auditory condition where videos cannot be viewed
• Presence of active cancer, a malignant hemopathy, drug addiction, coagulopathy, immunosuppressive treatment
• Non-acute or interval appendectomy, i.e. after antibiotic treatment of a complicated appendicitis of the plastron or drainage of an appendicular abscess;
• Vulnerable people: adult under guardianship, curator ship or deprived of freedom.
• Medication or pathology affecting ability to discern: Severe psychotic disorders
• Patient refusing to monitor anxiety and pain via smartphone
• Patient already medically monitored for anxiety, depressive or chronic pain syndrome