Efficacy of therapeutic suggestions under general anesthesia: a systematic review and meta-analysis of randomized controlled trials.

General anesthesia does not block central nervous processing of auditive information. Therefore, positive suggestions even given during surgery might have the potential to encourage well-being and recovery of patients. Aim of this review was to summarize the evidence on the efficacy of therapeutic suggestions under general anesthesia in adults undergoing surgery compared to an attention control (i.e. white noise).