Canine Malignant Hyperthermia
Canine malignant hyperthermia (MH) is autosomal dominant inherited disorder of skeletal muscle characterized by hypercarbia, rhabdomyolysis, generalized skeletal muscle contracture, cardiac dysrhythmia, and renal failure that develops on exposure to volatile anesthetics and depolarizing muscle relaxants. When given these agents, MH-susceptible dogs show tachycardia, muscle contractions, hyperthermia, elevated carbon dioxide production, and death if the anesthetic is not discontinued. Malignant hyperthermia is can be triggered in susceptible animals by excitement, apprehension, exercise, or environmental stress. Because of this reason, this disorder is also known as “canine stress syndrome.”
Canine malignant hyperthermia episodes usually come on unexpectedly and are very serious. If the condition is recognized early enough in an animal under anesthesia, certain measures can be taken in order to be able to save the animal. Some types of anesthesia can be fatal for dogs with malignant hyperthermia gene. This is why it is also important to identify dogs that carry the malognant hyperthermia gene prior to surgical procedures. Unfortunately, regardless of treatment, malignant hyperthermia is usually fatal. Some types of anesthesia can be fatal for dogs with malignant hyperthermia gene.
Roberts, M.C., Mickelson, J.R., Patterson, E.E., Nelson, T.E., Armstrong, P.J., Brunson, D.B., and Hogan, K. (2001). Autosomal Dominant Canine Malignant Hyperthermia Is Caused by a Mutation in the Gene Encoding the Skeletal Muscle Calcium Release Channel (RYR1 ). Anesthesiology 95, 716–725 – 716–725.