Bispectral Index-Monitored Anesthesia Technique for Transsternal Thymectomy

Abstract

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 40s. 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.

Risk factors of prolonged ventilation after thymectomy in thymoma myasthenia gravis patients

“…MG patients are more sensitive than normal to the neuromuscular depressant effects of halothane and isoflurane [ 21 , 22 ]. Maddali et al [ 23 ] reported the safety use of sevoflurane and propofol when real-time monitoring the depth of anesthesia in a small cohort of patients undergoing transthymectomy. In contrast, Nitahara et al [ 24 ] have reported that sevoflurane inhibits neuromuscular transmission in a dose-dependent fashion.…”

Myasthenia Gravis for Spine Surgery: An Ardous Anaesthetic Journey

“…We avoided succinylcholine in our patients to avoid prolonged blockade, as both of them were on cholinesterase inhibitor therapy [ 10 ]. We used lower doses of sevoflurane and propofol due to their desirable and proven pharmacological properties of rapid clearance, which were of benefit to these patients [ 11 ]. It is an established fact that reversal of neuromuscular blockade using Neostigmine is unpredictable in patients with MG, especially if they are taking anticholinesterase medication, which has been known to precipitate a cholinergic crisis.…”

Anesthetic implications in patients with myasthenia gravis undergoing spine surgery

“…In general anesthesia, we preferred a neuromuscular-free approach and inhalational-intravenous combination (Sevoflurane -propofol) with maintenance on a combination of O 2 , N 2 O, Sevoflurane, and Propofol. Among inhalational and intravenous agents, sevoflurane and propofol are the preferred agents, respectively, due to their pharmacological properties [11].…”