Emergency Protocols
Malignant Hyperthermia
Hypermetabolic crisis triggered by volatile anesthetics or succinylcholine
Clinical Signs
↑ EtCO₂Muscle rigidityTachycardiaHyperthermiaAcidosisHyperkalemia
MHAUS 24/7 Hotline
1-800-644-9737
Call immediately for expert guidance
Event Timer
00:00
1
Immediate Actions
  • STOP all triggering agents (volatile anesthetics, succinylcholine)
  • Call for HELP — assign roles, get MH cart
  • Hyperventilate with 100% O₂ at high flows (≥10 L/min)
    Use new circuit if available, otherwise flush with high flow
  • Switch to IV anesthesia (propofol, opioids, non-depolarizing NMB)
2
Dantrolene Administration
Dantrolene is the ONLY specific treatment
Do not delay administration. Each vial requires 60 mL sterile water — assign multiple people to mix.
  • Give Dantrolene IV bolus
    Repeat every 5 min until symptoms resolve (max 10 mg/kg initial)
    2.5 mg/kg IV push
  • For 70 kg patient: Start with 7 vials (175 mg)
    Dantrium: 20 mg/vial · Ryanodex: 250 mg/vial
3
Treat Complications
  • HYPERKALEMIA: Calcium chloride, insulin/glucose, bicarbonate
    CaCl 10 mg/kg IV · Insulin 10 units + D50
  • ACIDOSIS: Sodium bicarbonate for pH < 7.2
    NaHCO₃ 1-2 mEq/kg IV
  • ARRHYTHMIAS: Avoid calcium channel blockers with dantrolene
    Use amiodarone, lidocaine, or beta-blockers if needed
  • HYPERTHERMIA: Active cooling (ice packs, cold IV fluids, cooling blanket)
    Target temp < 38.5°C. Stop cooling at 38°C to prevent overshoot.
4
Labs & Monitoring
  • ABG, lactate, electrolytes (K+), CK, myoglobin
  • Arterial line, Foley catheter (monitor UOP, myoglobinuria)
  • Repeat labs q6h for 24-48 hours (CK may peak at 12-24h)
  • ICU admission — recrudescence occurs in 25% of cases
    Continue dantrolene 1 mg/kg q4-6h for 24-48h