Myasthenia gravis (MG) is one of the autoimmune diseases which blocks and destroys the receptor sites for acetylcholine. Since the patient has varying sensitivity to non-depolarizing neuromuscular blocking agents, it should be carefully treated by titrating the muscle relaxing drug for anesthesia. The newly-development of the neuromuscular blockade provides the more precise information of the extent of muscle relaxation, thus, muscle relaxant can become safely used for even the patient with MG. Herewith, we report a case of MG anesthetized for extraction of the wisdom tooth.
The patient is a 56-year-old woman. 157 cm, 50 kg. At the age of 52, she was diagnosed with MG. Since the wisdom teeth was deeply impacted, general anesthesia was indicated. It was planned to monitor muscle relaxation by using TOF-cuff®, which is a type of Compressomyography : CMG. This monitor is built in the manchette for measurement of blood pressure. Thus, this monitor is feasible for a case of dental anesthesia because the monitoring condition is not affected by the position of the finger, and is not needed to align the position if necessary.
General anesthesia was induced with remifentanil 0.5 μg/kg/min and propofol 70 mg. The rocuronium bromide was repeatedly administered by 5 mg, monitoring TOFcuff®. We confirmed null TOF count by 20 mg, and the patient was intubated. The neuromuscular blocking condition was stable during the operation by titrating each 5 mg of rocuronium bromide as needed. After the surgery, 100 mg of the sugammadex successfully revered neuromuscular blockade, confirming the 100% recovery of the TOF ratio. The patient was postoperatively uneventful, no complication was confirmed.
It is still controversial whether muscle relaxant should be used for the patient with MG. The precise monitoring of muscle relaxation could lead to safety usage of muscle relaxation even for MG. The compressomyography may become a useful monitor intraoperatively. This case report could be a reference to consider muscle relaxation for the patient with MG.
