Which of the following are symptoms of malignant hyperthermia?

• A. Rash, itching, edema
• B. High fever, rigid jaw, tachypnea, tachycardia
• C. Hypothermia, hypotension, bradycardia, fatigue
• D. Chest pain, diaphoresis, low heart rate

Answer: (B)

Recognizing malignant hyperthermia during anesthesia comes down to its rapid hypermetabolic signs. The hallmark is a sudden rise in body temperature along with skeletal muscle rigidity, often starting with the jaw, and a fast respiratory rate and heart rate as the body’s metabolism spikes from an abnormal calcium release in the muscles. This combination—high fever, rigid jaw, tachypnea, and tachycardia—best fits the crisis caused by triggering anesthetic agents. Other options describe symptoms more typical of allergic reactions (rash, itching, edema) or different acute conditions (hypothermia with hypotension or chest pain with diaphoresis and bradycardia), which do not match malignant hyperthermia. In practice, recognizing this pattern prompts immediate actions: stop the triggering agent, administer dantrolene, provide 100% oxygen, begin cooling measures, and monitor and correct metabolic derangements.