Introduction to moderate and deep sedation

History of sedation Some have argued that the development of sedation and analgesia may be one of the preeminent advances in both medical science and human technology. The power to manipulate and alter human consciousness and perception of pain has opened the door to extraordinary possibilities for medical practice. However, the origins of these advances reach far back to the limits of written history. Ancient Greeks recognized that naturally occurring substances such as mandrake root and alcohol could alter consciousness and be used during surgical manipulations [1, 2]. Inca shamans used coca leaves to assist in trephination operations in which burr holes drilled into the skull were thought to cure illnesses [1]. And surgeons in the Middle Ages used ice and so-called “refrigeration anesthesia” to dull pain sensation prior to incision [2, 3]. The modern practice of sedation is the end result of a process of evolution in alteration of consciousness, likely starting with the discovery of the analgesic properties of ether [1, 4]. A medical student from Rochester, New York, named William Clarke used ether during a tooth extraction in January 1842. Many believe that this procedure may have been the first successful use of ether. Sedative technique using ether was further developed by Crawford Long during a neck tumor excision [1, 4, 5]. Later in 1842, Horace Wells would be the first to give a public demonstration at Massachusetts General Hospital. Unfortunately, when the patient cried out in pain, he was ridiculed and the use of ether was called “humbug” [1, 4, 5]. William Morton later would return to the same “Ether Dome” at Massachusetts General Hospital to successfully demonstrate the use of ether [1, 5, 6].