1. Presented by Joshua Ward

2.  Rare, life-threatening condition triggered by drugs used for general anesthesia  Causes uncontrolled increase in skeletal muscle metabolism  Susceptibility is inherited as autosomal dominant disorder

3.  Early signs  Hypercapnia  Tachycardia  Masseter muscle rigidity  Late signs  ECG changes, arrhythmias  Rhabdomyolysis  Hyperthermia

4.  Intubation (if not already intubated)  Oxygenation and ventilation  ↑ inspired O2 to 100%; increase ventilation rate/tidal volume  Discontinue offending agents  Administer dantrolene  Only known antidote  Binds ryanodine receptors and blocks sarcoplasmic reticulum Ca release  Monitor for hyperkalemia and check labs  Initiate supportive care

5.  Place in ICU  Continue maintenance dosing of dantrolene  48 hrs after last observed sign  Counsel patient  Avoid anesthesia with triggering agents  Avoid excessive heat and humidity  Inform family members

6. Resources 1. UpToDate, Malignant Hyperthermia: Clinical diagnosis and management of acute crisis, http://www.uptodate.com/contents/malignant-hyperthermia-clinical- diagnosis-and-management-of-acute- crisis?source=search_result&search=malignant+hyperthermia&selectedT itle=1~72 2. Rosenberg H, Davis M, James D, Pollock N, Stowell K. Malignant hyperthermia. Orphanet J Rare Dis. 2007;2:21.