The rare but very serious condition of malignant hyperthermia (MH) remains a risk at all surgical facilities, including ambulatory surgical centers (ASCs). MH occurs in about one in 50,000 adults under anesthesia, and one in about 12,000 children, which translates to one or two deaths annually in the United States. When it does strike, MH often is fatal if not treated within minutes. And the only antidote is a very expensive drug.