Malignant Hyperthermia
Malignant Hyperthermia
Malignant Hyperthermia (MH) is a potentially life-threatening reaction to certain types of anesthetic agents. It is a type of metabolic disorder which is triggered by the use of certain inhaled anesthetics or depolarizing muscle relaxants. During MH episodes, muscle rigidity and the body's core temperature may soar dangerously and irreversible damage to organs can occur if not treated quickly and correctly. Since its first description in the literature in 1961, it has become better understood and treatments have advanced.
Malignant Hyperthermia is primarily a disorder of skeletal muscle, though other tissues are also affected. It is caused by an abnormal reaction to certain commonly used anesthesia agents. When exposed to these agents (inhaled anesthetics, amidation reactions to nitrous oxide, inhalation of carbon dioxide, and intravenous anesthetic agents), some individuals abruptly develop high fever, muscle rigidity, and acidosis.
The symptoms of Malignant Hyperthermia may include the following:
- Rapid increase in temperature to 40°C or higher
- Muscle rigidity
- Elevated blood carbon dioxide
- Increase in muscle enzymes in the blood
- Increased heart rate and blood pressure
- Cardiac arrhythmias
- Respiratory acidosis
Treatment of Malignant Hyperthermia is critical and includes prompt discontinuation of the triggering agent, intravenous dantrolene sodium, supportive care, cooling measures if needed, and monitoring of vital signs and clinical improvement. Avoidance of triggering agents and other preventive measures should be discussed with patients at risk.
Malignant Hyperthermia is a rare but potentially life-threatening syndrome. It is important to be aware of its characteristics and the appropriate treatments so that it can be recognized and managed quickly.