Malignant hyperthermia (MH) is a rare, inherited muscle membrane disorder which leads to a hypermetabolic state. It is triggered by suxamethonium and volatile anaesthetic agents. It can lead to multiorgan failure and death.

Features include:

• Rising end tidal CO₂
• Tachycardia
• Pyrexia
• Masseter spasm

Management:

• Stop the trigger agent and hyperventilate with 100% O₂
• Intravenous dantrolene, initially 2-3 mg/kg
• Measures to actively cool the patient

Click on the Resources button for a link to the AAGBI guideline for treating MH crisis.