During a surgery a patient developed muscle rigidity, increased hea rate and hypercarbia. Emergence of malignant hypehermia is suspected. The agent which precipitates this condition most commonly is:

Malignant hypehermia (MH) is commonly triggered by the administration of anesthetic agents; the commonest trigger is the depolarizing muscle relaxant succinylcholine alone or in conjunction with a volatile agent such as halothane. The earliest signs of MH during anesthesia are succinylcholine-induced masseter muscle rigidity (MMR) or other muscle rigidity, tachycardia, and hypercarbia (due to increased CO2 production). Hypehermia may be a late sign, but when it occurs, core temperature can rise as much as 1degC every 5 min. The treatment of choice is intravenous dantrolene. Drugs known to trigger malignant hypehermia: Inhaled general anesthetics Ether Halothane Methoxyflurane Enflurane Isoflurane Desflurane Sevoflurane Nondepolarizing muscle relaxants Succinylcholine Ref: Butterwoh IV J.F., Butterwoh IV J.F., Mackey D.C., Wasnick J.D., Mackey D.C., Wasnick J.D. (2013). Chapter 11. Neuromuscular Blocking Agents. In J.F. Butterwoh IV, J.F. Butterwoh IV, D.C. Mackey, J.D. Wasnick, D.C. Mackey, J.D. Wasnick (Eds), Morgan & Mikhail's Clinical Anesthesiology, 5e.Ether