Ethics and the practice of anesthesia.

Anesthesia began in 1846, when an American dentist administered diethyl ether to a patient undergoing neck surgery [1]. Initially, anesthesia practice was limited to rendering patients unconscious and without pain or movement during surgery. Over the course of the next century, new knowledge, technology, and drugs enabled anesthesiologists to manage physiologic derangements caused by anesthetics and surgery [1]. Although the care of patients undergoing surgery remained the mainstay of anesthesia practice, it soon expanded to include the management of all types of pain.