This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anaesthesia
[{'content': 'A inhalation anaesthetic agent was used in a surgery which caused high output renal failure. The agent is: \nSelect and explain. \nA. Methoxyflurane, B. Diethyl ether, C. Enflurane, D. Halothane', 'role': 'user'}, {'content': "Answer: A \nExplanation: Methoxyflurane was the most potent inhalation agent, but its high solubility and low vapor pressure yielded longer inductions and emergences. Up to 50% of it was metabolized by cytochrome P-450 (CYP) enzymes to free fluoride (F-), oxalic acid, and other nephrotoxic compounds. Prolonged anesthesia with methoxyflurane was associated with a vasopressin-resistant, high-output, renal failure that was most commonly seen when F- levels increased to greater than 50 micro mol/L. Ref: Butterwoh IV J.F., Butterwoh IV J.F., Mackey D.C., Wasnick J.D., Mackey D.C., Wasnick J.D. (2013). Chapter 8. Inhalation Anesthetics. 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.", 'role': 'assistant'}]