The term “anesthesia” was first coined in 1846 by Oliver Wendell Holmes, a doctor, poet, and writer. The term originates from the Greek word, anaisthaesia, meaning “without sensation.”
Modern anesthesia incorporates the ideal of a reversible, controlled state of unconsciousness by depression of the central nervous system and analgesia. It has been further divided in to subsequent terms including local anesthesia, regional anesthesia, surgical anesthesia, dissociative anesthesia and balanced anesthesia.
Local anesthesia, interchangeable with local analgesia, is described by the technique of using local anesthetics to remove feeling of sensation from a specific body part. Regional anesthesia also interchangeable with regional analgesia, is very similar to local anesthesia but incorporates a block that provides an effect to a larger region of the body such as with an epidural. Surgical anesthesia provides a state where the patient does not respond to noxious stimulation (i.e. cannot be aroused) and has analgesia and sufficient muscle relaxation for surgery. Dissociative anesthesia is induced with ketamine or tiletamine drugs and characterized by a maintenance of reflexes and open eyes.
Balanced anesthesia is the ultimate goal of every anesthetic event. Its goal is to combine the benefits of multiple drugs to provide unconsciousness, analgesia, and muscle relaxation. The responsible, carefully calculated use of multiple drugs allows for lower doses, reduced side effects and maximum benefits.