anesthetics induce a different sort of anesthetic state, one of general insensibility to pain. The patient loses awareness yet his vital physiologic functions, such as breathing and maintenance of blood pressure, continue to function. Less is known about the mechanism of action of general anesthetics compared to locals, despite their use for more than 150 years. The most commonly used general anesthetic agents are administered by breathing and are thus termed inhalational or volatile anesthetics. They are structurally related to ether, the original anesthetic. Their primary site of action is in the central nervous system, where they inhibit nerve transmission by a mechanism distinct from that of local anesthetics. The general anesthetics cause a reduction in nerve transmission at synapses, the sites at which neurotransmitters are released and exert their initial action in the body.
