Malignant Hyperthermia Flashcards
1
Q
What is malignant hyperthermia?
A
Malignant hyperthermia is a hypermetabolic state caused by succinylcholine or halogenated volatile anesthetics in genetically susceptible patients.
2
Q
What are the clinical features of malignant hyperthermia?
A
- Hyperthermia (rapid, sustained rise)
- Rigidity
- Activation of SNS - tachycardia, HTN, tachypnea, arrhythmias
- Acidosis (elevated EtCO2), hyperkalemia
- Rhabdomyolysis (elevated CK)
- Acute kidney injury - myoglobinuria
3
Q
What is the differential diagnosis when suspecting malignant hyperthermia?
A
- MH
- Neuroleptic malignant syndrome
- Thyroid storm
- Anaphylaxis
- Pheochromocytoma
- Drug toxicity
- Other causes of fever (infection, malignancy, autoimmune)
4
Q
What is the management of malignant hyperthermia?
A
- Exclude other potential causes
- Stop offending anesthetic and stop surgery
- Hyperventilate with 100% oxygen
- Call for help
- Dantrolene 2.5mg/kg IV, repeat PRN
- Cool patient (IV fluids, ice packs, cavity lavage
- Treat arrhythmias (avoid calcium channel blockers)
- Sodium bicarbonate 1 to 2 mEq/kg PRN
- Monitor temperature, electrolytes, arterial/venous blood gases, CK, urine output, coag studies
- Monitor recurrence - continue dantrolene 1mg/kg q4 to q6 for two days
- Refer for genetic counseling/in-vitro muscle contracture
5
Q
What is dose of dantrolene for malignant hyperthermia?
A
2.5mg/kg dantrolene IV PRN, followed by 1mg/kg q4 to q6 for 48 hours to prevent recurrence.
