Dreaming during anaesthesia in patients at high risk of awareness

Dreaming during anaesthesia is commonly reported but remains poorly understood. In this study, adult surgical patients at high risk of awareness were randomly assigned to receive bispectral index (BIS)-guided anaesthesia or routine care, and were interviewed about dreaming three times postoperatively. Dreaming patients (n = 134) were compared with all other patients who were interviewed at least once (n = 2251). Intraoperative dreaming was reported by 4.2%, 3.9% and 3.4% of patients at 2-4 h, 24-36 h and 30 days after surgery, respectively. Fewer BIS-monitored patients reported intra-operative dreaming at 2-4 h than control patients (2.7% vs. 5.7%; p = 0.004). Reports of dreaming were similar in the two groups at 24-36 h and 30 days. Dreaming patients were younger (p = 0.001); healthier (p < 0.001) and more likely to be women (p < 0.001), and were less satisfied with anaesthetic care (p = 0.004) than other patients.