Malignant hyperthermia

[Rihanna]

Malignant hyperthermia is a rare, life-threatening rise in body temperature that occurs in susceptible people who are given certain muscle-relaxing drugs plus an anesthetic gas for surgery.

Malignant hyperthermia can occur when the anesthesia is given or during or soon after surgery.
Muscle cells become overactive, causing sustained muscle contractions that produce heat and raise body temperature extremely high.
Symptoms include muscle rigidity, rapid heart rate, and rapid breathing
Doctors diagnose malignant hyperthermia based on symptoms in people who have just had surgery.
Treatment is rapid cooling.

(See also Overview of Heat Disorders.)
Malignant hyperthermia usually develops after a person receives a muscle relaxant (most often succinylcholine ) along with an anesthetic gas (most often halothane) for surgery. Although malignant hyperthermia may develop after the first use of these drugs, people usually develop the condition only after about three exposures. Susceptibility to malignant hyperthermia is an inherited genetic trait that runs in families.
Malignant hyperthermia may cause imbalances in body salts (electrolytes) and blood clotting. Excessive blood clotting (disseminated intravascular coagulation) causes organ damage, followed by excessive bleeding when the body runs out of clotting factors.
Malignant hyperthermia can also cause significant muscle damage. Damaged muscles release the protein myoglobin, which turns the urine brown or bloody. This condition (myoglobinuria) can lead to acute kidney injury or even kidney failure. Death may occur.