title: Malignant hyperthermia in a patient with Graves' disease during subtotal thyroidectomy.
abstract: We report the case of a 31-year-old man with Graves' disease who manifested malignant hyperthermia during subtotal thyroidectomy. His past medical history and family history were unremarkable. Before surgery, his condition was well controlled with propylthiouracil, beta-adrenergic blocker and iodine. During the operation, anesthesia was induced by intravenous injection of vecuronium and thiopental, followed by suxamethonium for endotracheal intubation. Anesthesia was maintained with nitrous oxide and sevoflurane. One hour after induction of anesthesia, his end tidal carbon dioxide concentration (ET(CO2)) increased from 40 to 50 mmHg, heart rate increased from 90 to 100 beats per min and body temperature began to rise at a rate of 0.3 degrees C per 15 min. Suspecting thyroid storm, propranolol 0.4 mg and methylprednisolone 1,500 mg were administered, which, however, had little effect. Despite the lack of muscular rigidity, the diagnosis of malignant hyperthermia was made based on respiratory acidosis. Sevoflurane was discontinued and dantrolene was given by intravenous bolus. Soon after the treatment, ET(CO2), heart rate and body temperature started to fall to normal levels. His laboratory findings showed abnormally elevated serum creatine phosphokinase and myoglobin but normal thyroid hormone levels. Since dantrolene is efficacious in thyrotoxic crisis and malignant hyperthermia, an immediate intravenous administration of dantrolene should be considered when a hypermetabolic state occurs during anesthesia in surgical treatment for a patient with Graves' disease.
authors.affiliation: Department of Internal Medicine, Hamamatsu University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Nishiyama
authors.forename: A
authors.initials: A
authors.lastname: Kitahara
authors.forename: H
authors.initials: H
authors.lastname: Natsume
authors.forename: A
authors.initials: A
authors.lastname: Matsushita
authors.forename: K
authors.initials: K
authors.lastname: Nakano
authors.forename: S
authors.initials: S
authors.lastname: Sasaki
authors.forename: R
authors.initials: R
authors.lastname: Genma
authors.forename: Y
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: H
authors.initials: H
authors.lastname: Nakamura
mesh_terms: D000142:Acidosis, Respiratory / Q000175:diagnosis; D000328:Adult; D000777:Anesthetics / Q000008:administration & dosage / Q000009:adverse effects*; D013956:Antithyroid Agents / Q000627:therapeutic use; D002245:Carbon Dioxide / Q000032:analysis; D003402:Creatine Kinase / Q000097:blood; D003620:Dantrolene / Q000627:therapeutic use; D003937:Diagnosis, Differential; D006042:Goiter / Q000175:diagnosis; D006111:Graves Disease / Q000188:drug therapy / Q000601:surgery*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008305:Malignant Hyperthermia / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology; D008713:Methimazole / Q000627:therapeutic use; D008738:Methyl Ethers / Q000008:administration & dosage / Q000009:adverse effects; D009125:Muscle Relaxants, Central / Q000627:therapeutic use; D009211:Myoglobin / Q000097:blood; D009609:Nitrous Oxide / Q000008:administration & dosage; D011441:Propylthiouracil / Q000627:therapeutic use; D000077149:Sevoflurane; D013390:Succinylcholine / Q000008:administration & dosage; D013874:Thiopental / Q000008:administration & dosage; D013965:Thyroidectomy; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D014673:Vecuronium Bromide / Q000008:administration & dosage
chemical_list: D000777:Anesthetics; D013956:Antithyroid Agents; D008738:Methyl Ethers; D009125:Muscle Relaxants, Central; D009211:Myoglobin; D014284:Triiodothyronine; D002245:Carbon Dioxide; D000077149:Sevoflurane; D008713:Methimazole; D011441:Propylthiouracil; D014673:Vecuronium Bromide; D003402:Creatine Kinase; D003620:Dantrolene; D013390:Succinylcholine; D013874:Thiopental; D009609:Nitrous Oxide; D013974:Thyroxine