Malignant Hyperthermia is one of the most devastating anesthesia related complications. It is a pharmacogenetic clinical syndrome that in its classical form. occurs during anesthesia with volatile halogenated alkanes such as halothane. isoflurance/ desflurance, and /or muscle relaxant like succinylcholine.
The Fulminant malignant hyperthermia produce muscle hypermetabolism with rapidly increasing body temperature by as much as 1ºC in 5 minutes ,and extreme acidosis as a result of acute loss of control of intracellular ionized calcium.
About 50-80% of the genotyped patients had their disease linked to the RyR1 gene and L-type Ca2t channel
- Elevated end-tidal CO2
- Tachynea and/or Tachycardia
- Masseter Spasm(with succinylcholine)
- Generalized muscle rigidity
- Metabolic+ Respiratory acidosis
- Profuse sweating
- Mottling of skin
- Cardiac Arrchythmias
- Unstable blood pressure
- Rapid ↑ in cone Body Temp
- ↑ creatine phosphokinases
- Cardiac Arrest
Treatment of Malignant Hyperthermia
- Discontinue all triggering agents.
- Hyperventilate with 100% Oxygen with a fresh flow to atleast 10 L/min.
- IV Dantrolene 2.5mg/kg to a total dose of 10mg/kg every 5-10 minutes until symptoms subside.
- Bicarbonate (1-4 mEq/Kg IV) to correct metabolic acidosis.
- Fever control: Iced fluids, cooing body surface, and if necessary, use a heat exchanger with a pump Oxygenator cooling should be halted at 38ºC to prevent inadvertent Hypothermia.
- Monitor and treat arrhythmias
- Maintain urinary output >1-2ml/kg/h
- Hyperkalemia if present, treat with bicarbonates ,glucose, and insulin (10U of regular insulin and 50ml of 50% Dextrose)
- Analyze coagulation studies, blood gases, temperature, muscle tone, electrolytes, urine output, CK
- Once initial reaction is controlled, continue monitoring in the ICU for 24-48 hours