Steroid-induced rapid recovery from respiratory dysfunction in a patient with myasthenia gravis after spinal anesthesia.

We report an 83-year-old man with myasthenia gravis (MG) who developed respiratory depression after spinal anesthesia for transurethral laser enucleation of the prostate. He became less responsive after complained of dyspnea, with a decrease of SpO2 to 83% approximately 13 min after intrathecal administration of 0.5% isobaric bupivacaine 3 ml. With a diagnosis of exacerbation of MG, hydrocortisone 100 mg was administered, following which both consciousness and spontaneous respiration rapidly improved. Cold sense was observed below the C4 dermatome. We provided general anesthesia without using muscle relaxants until disappearance of the effect of spinal anesthesia. Surgery completed uneventfully and confirmed wearing off the local anesthetics effect. He was discharged without respiratory problems on postoperative 3 day.