Mnemonic for Malignant hyperthermia treatment
"Some Hot Dude Better Give Iced Fluids Fast!"
Stop triggering agents
Hyperventilate/ Hundred percent oxygen
Dantrolene (2.5mg/kg)
Bicarbonate
Glucose and insulin
IV Fluids and cooling blanket
Fluid output monitoring/ Furosemide/ Fast heart [tachycardia]
Here are some key points to review for malignant hyperthermia (MH) for your board exams:
Definition: Malignant Hyperthermia is a life-threatening hypermetabolic reaction to certain anesthetic agents, such as volatile anesthetics (e.g., halothane, sevoflurane) and the depolarizing muscle relaxant succinylcholine. It is often triggered in genetically susceptible individuals, typically due to mutations in the RYR1 gene.
Early Signs and Symptoms:
- Increased end-tidal CO2: One of the earliest and most sensitive indicators.
- Muscle rigidity: Especially masseter muscle rigidity after succinylcholine administration.
- Tachycardia and tachypnea.
Late Signs and Symptoms:
- Hyperthermia: Rapid rise in body temperature.
- Rhabdomyolysis: Muscle breakdown leading to elevated serum creatine kinase (CK) levels.
- Acidosis: Both metabolic and respiratory.
- Hyperkalemia: Elevated potassium levels.
Management:
- Immediate discontinuation of triggering agents.
- Dantrolene: The only specific treatment for MH, administered intravenously.
- Supportive measures: Cooling the patient, correcting acidosis, and managing electrolyte imbalances.
Prevention:
- Preoperative screening: Detailed family and personal history to identify at-risk individuals.
- Avoidance of triggering agents in susceptible patients.
Definitive diagnosis: Muscle biopsy with caffeine-halothane contracture test.
Emergency preparedness: MH cart with dantrolene and other emergency supplies should be readily available in operating rooms.