Postanesthetic equine myopathy suggestive of malignant hyperthermia. A case report.
Signs of malignant hyperthermia, including progressive increases in PaCO2, skin temperature and heart rate, and elevated serum levels of potassium, inorganic phosphate, and creatine kinase, were identified in a halothane-anesthetized horse. Treatment was discontinuing halothane administration, applying ice and cold fluids, and hyperventilating with 100% oxygen. After an initial recovery, bilateral hindlimb myopathy and pigmenturia developed. The myopathy resolved after treatment with oral dantrolene, IV fluids, and hydrocortisone. Results of caffeine-halothane challenge, using semimembranosus muscle collected 2 weeks after the episode, were considered within normal limits for horses. The intraoperative abnormalities were evidently predictive of postanesthetic myopathy but the cause in this horse remained unclear.
Klein
L
L
Department of Clinical Studies, University of Pennsylvania School of Veterinary Medicine, New Bolton Center 19348.
Ailes
N
N
Fackelman
G E
GE
Kellon
E
E
Rosenberg
H
H
D000768:Anesthesia, General / Q000009:adverse effects / Q000662:veterinary*; D000818:Animals; D005260:Female; D006221:Halothane; D006734:Horse Diseases / Q000209:etiology*; D006736:Horses; D008305:Malignant Hyperthermia / Q000209:etiology / Q000662:veterinary*; D009135:Muscular Diseases / Q000209:etiology / Q000662:veterinary*
D006221:Halothane