General anesthesia is, essentially, a medically induced coma, not sleep. Drugs render a patient unresponsive and unconscious. They are normally administered intravenously (IV) or inhaled. Under general anesthesia, the patient is unable to feel pain and may also have amnesia. The drugs will be administered by an anesthesiologist or nurse anesthetist, a specially trained doctor or nurse who will also monitor a patient’s vital signs and rate of breathing during the procedure. General anesthetics have been widely used in surgery since 1842, when Crawford Long administered diethyl ether to a patient and performed the first painless operation.