Recall of music: a comparison between anaesthesia with propofol and isoflurane

Sixty patients undergoing laparoscopy were randomly assigned to receive total intravenous anaesthesia with propofol or inhalation anaesthesia with isoflurane. Patients in these two groups were also randomly assigned to three subgroups listening to soft music, hard rock music or no music at all. Twenty-four hours after surgery all patients were interviewed and asked if they had heard music during the operation. A tape with seven different pieces of music was also played for the patients. The music they heard during surgery was one of these. No patient had any memories or experiences from the operation. Four patients had dreams, three from the total intravenous anaesthesia group and one from the inhalation anaesthesia group. Twelve patients believed they had heard music, ten from the total intravenous anaesthesia group and two from the inhalation anaesthesia group (P < 0.05). Two patients, one from each group, picked the right melody. In conclusion, there was no difference between the two groups with respect to recall during anaesthesia. Patients in the TIVA group were significantly more inclined to state that they had been exposed to music.