Anesthesia

Anesthesia is divided into two categories: general and local. Local anesthesia depresses sensory nerves and blocks conduction of pain impulses from their site of origin. Sensory nerves are affected first. When only an anesthetic drug is used, the patient remains conscious. Sedation may be given to relieve anxiety and to produce amnesia. General anesthesia is central nervous system depression which effects an individual totally.

Salient features of modern anesthesia include assessment of patients preoperatively; selection of appropriate agents and techniques; management of induction, maintenance and emergence processes; and continuous monitoring of vital functions during anesthesia. The American Society of Anesthesiologists (ASA) founded in 1905, and the American Association of Nurse Anesthetists (AANA) founded in 1931, have established guidelines and standards for safely administering and monitoring anesthesia care. The ASA also developed the taxonomy for classifying patients by physical status from Class I, the lowest risk, to Class VI, the highest risk. Historically, specialists in anesthesia have been advocates of patient safety and risk management. With the proliferation of pain clinics anesthesiologists have essential roles in multidisciplinary teams concerned with management of acute and chronic pain. Because of their familiarity with anesthetic drugs, nerve pathways, and nerve block techniques, anesthesiologists are well qualified to assess and treat pain.