Can we sooth the subconscious during general anaesthesia?

Around the globe, more than 200 million people have surgery each year, mostly under general anaesthesia.1 Although often a concern for patients, awareness—the explicit recall of events—under anaesthesia is rare (<2 per 1000 general anaesthetics2). However, a state of connected consciousness, when patients respond to external stimuli while under general anaesthesia but do not experience any explicit recall, is more common (50 to 300 per 1000).3 Typically, any signs of awareness or connected consciousness are perceived unfavourably; understandably anaesthesia providers and their patients strive to avoid any negative experience or recall of unpleasant surgical stimuli.45 As highlighted in the linked paper, however, a state of connection to the external environment without recall might also represent an opportunity to improve patients’ perioperative outcomes.6

In their multicentre trial at five German tertiary care centres, Nowak and colleagues (doi:10.1136/bmj.m4284) found that in adults receiving general anaesthesia for elective surgeries of 1-3 hours duration, exposure to a recording of therapeutic suggestions accompanied by relaxing music led to a small (4 mg …