2. a drug or agent used to abolish the sensation of pain, to achieve adequate muscle relaxation during surgery, to calm fear and allay anxiety, and to produce amnesia for the event.
Inhalational anesthetics are gases or volatile liquids that produce general anesthesia when inhaled.
Older agents, such as ether and cyclopropane, are now used infrequently. The mechanism of action of all inhalational anesthetics is thought to involve the uptake of the gas in the lipid bilayer of cell membranes and some interaction with the membrane proteins, resulting in an inhibition of the synaptic transmission of nerve impulses. For surgical anesthesia, these agents are usually used with preanesthetic medication, which includes sedatives or opiates to relieve preoperative and postoperative pain and tranquilizers to reduce anxiety. Neuromuscular blocking agents are used to produce complete muscular relaxation during surgery. They include tubocurarine, metocurine, succinylcholine, pancuronium, atracurium, vecuronium, and pipecuronium.