Résumé
Hypnosis is considered a state of consciousness involving focused attention and reduced peripheral awareness. Its definition has changed over time and the notions of "dynamic process of consciousness'', modulation of "agentivity'' and "connectome'' seem more adapted to current neuroscience. Imagery shows, with regard to pain, a multimodal action of hypnosis, centered on the anterior cingulum, which is a complex network associating primary and associative regions (precuneus, cerebellum). Used to modulate brain activation, hypnosis is a tool that can be inserted among other therapies, especially drugs, and must remain at the service and within the limits of its field of competence. Informal or conversational hypnosis allows perioperative management adapted to consultations and patient preparation (including regional anaesthesia). Hypnosis is likely to be effective for most people suffering from diverse forms of pain, with the possible exception of a minority of patients who are resistant to hypnotic interventions. Hypnoanalgesia and sedation are on the rise for interventional radiology and surgery (including oncology), as they reduce pain and drug consumption. They require the involvement of operators (i.e. surgeons) and a formalisation of the care process from the anaesthesia consultation to the performance of the procedure. Initial training (> 100 h) should be done, at best, by anaesthetists for anaesthetists (ethical charter) and include exercises, videos and demonstrations.