Sleep Disturbances after Posterior Scoliosis Surgery with an Intraoperative Wake-up Test Using Remifentanil

The intraoperative wake-up test is a standard procedure for early recognition of neurologic complications after posterior correction of idiopathic scoliosis. In this prospective, single-blinded cohort study, the impact of the wake-up test and the opioid used for anesthesia on the quality of the patients' sleep after scoliosis surgery was investigated up to 12 months postoperatively. Patients were classified into three groups: posterior instrumentation with wake-up test using remifentanil, anterior instrumentation without wake-up test using sufentanil, and posterior instrumentation with wake-up test using sufentanil. The quality of sleep was assessed using the Pittsburgh Sleep Quality Index questionnaire preoperatively as well as 3, 6, and 12 months postoperatively. In addition, data were collected on patients' age, weight, and sex, as well as the duration of the operation and anesthesia, amount of blood loss, specific opioid dosages, and wake-up test times. Statistical analysis was conducted using the Mann-Whitney, Kruskal-Wallis, and Wilcoxon tests. There were no differences between groups with regard to baseline characteristics. No explicit recall was assessed through all groups. At 3 and 6 months postoperatively, the sleep quality in the posterior-remifentanil group was significantly poorer than preoperatively and compared with the anterior- and posterior-sufentanil groups. No significant differences in wake-up test times between groups undergoing posterior instrumentation occurred. This study suggests that patients undergoing scoliosis surgery with an intraoperative wake-up test using remifentanil had impaired sleep quality that lasted up to 6 months postoperatively. No deterioration in sleep quality was observed with sufentanil. Large randomized trials are now needed to confirm these preliminary results.