title: Successful treatment of hyperkalaemic periodic paralysis in a horse during isoflurane anaesthesia.
abstract: METHODS
  A 3-year-old, 400 kg, gelding Quarter Horse was presented for investigation of epistaxis.
  
  
  METHODS
  The horse was bright, alert and responsive with rectal temperature, heart rate and respiration rate within normal limits.
  
  
  RESULTS
  During a second general anaesthetic for surgical treatment of guttural pouch mycosis by balloon-tipped catheter occlusion of the right major palatine artery and ligation of the right external carotid artery, signs consistent with hyperkalaemic periodic paralysis (HYPP) were exhibited. These included concurrent hyperkalaemia, hypercapnoea, sinus tachycardia, and muscle fasciculations in the presence of normothermia. Stress associated with an acute haemorrhage pre-operatively, and intra-operative hypercapnoea may have precipitated the episode. There were no signs of HYPP during a general anaesthetic, 1 week earlier, when an initial attempt at surgical treatment of guttural pouch mycosis was performed. Treatment consisted of fluid therapy and administration of calcium gluconate (0.1-0.2 mg kg(-1) minute(-1)), dextrose 5% (5 mL kg(-1) hour(-1)) and insulin (0.05 IU kg(-1)). Treatment resulted in the resolution of clinical signs and an uneventful recovery.
  
  
  RESULTS
  The diagnosis of HYPP was confirmed by DNA analysis post-operatively.
  
  
  CONCLUSIONS
  Clinical cases of intra-operative HYPP can present despite a previous history of uneventful general anaesthesia. Rapid diagnosis and treatment can result in the successful management of HYPP. This report documents an unusual presentation of HYPP, a disease that remains present in the Quarter Horse population.
authors.affiliation: Department of Veterinary Clinical and Diagnostic Services, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada. dsjpang@ucalgary.ca
authors.forename: Daniel S J
authors.initials: DS
authors.lastname: Pang
authors.forename: Luca
authors.initials: L
authors.lastname: Panizzi
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Paterson
mesh_terms: D018685:Anesthetics, Inhalation / Q000009:adverse effects*; D000818:Animals; D002125:Calcium Gluconate / Q000627:therapeutic use; D005440:Fluid Therapy / Q000662:veterinary; D005947:Glucose / Q000627:therapeutic use; D006734:Horse Diseases / Q000139:chemically induced* / Q000628:therapy; D006736:Horses; D006935:Hypercapnia / Q000139:chemically induced / Q000628:therapy / Q000662:veterinary; D006947:Hyperkalemia / Q000139:chemically induced / Q000628:therapy / Q000662:veterinary; D007328:Insulin / Q000627:therapeutic use; D007530:Isoflurane / Q000009:adverse effects*; D008297:Male; D020513:Paralysis, Hyperkalemic Periodic / Q000139:chemically induced / Q000628:therapy / Q000662:veterinary*; D013616:Tachycardia, Sinus / Q000139:chemically induced / Q000628:therapy / Q000662:veterinary
chemical_list: D018685:Anesthetics, Inhalation; D007328:Insulin; D007530:Isoflurane; D005947:Glucose; D002125:Calcium Gluconate