Bispectral Index-Monitored Anesthesia Technique for Transsternal Thymectomy

To evaluate the role of bispectral index monitoring as an adjunct to balanced anesthesia in patients with myasthenia gravis undergoing transsternal thymectomy without the use of neuromuscular blocking agents, 10 patients were enrolled into this prospective observational study. After oral midazolam premedication, general anesthesia was induced with fentanyl, propofol, and sevoflurane. Tracheal intubation was performed without neuromuscular blocking agents. During maintenance, continuous monitoring of physiological and bispectral index parameters was used to titrate the doses of remifentanil, propofol, and sevoflurane. Sevoflurane concentration and propofol doses were adjusted to achieve bispectral index values in the high 30s to low 40 s. Propofol was discontinued when the sternum was approximated. Remifentanil infusion was stopped on subcutaneous tissue closure, and sevoflurane was switched off when nearing completion of skin closure. Tracheal extubation was performed when extubation criteria were met. On extubation, bispectral index levels were above 90. The median time from extubation to discontinuation of propofol was 28 ± 4 min, that of remifentanil was 21 ± 4 min, and it was 9 ± 5 min for sevoflurane. Bispectral index monitoring provided excellent hemodynamic control during surgery, and allowed early problem-free tracheal extubation.