In the context of surgery, what does the term "inhalation agents" refer to?

Inhalation agents are specifically defined as gaseous anesthetics that are delivered directly into the lungs for the purpose of inducing and maintaining general anesthesia during surgical procedures. This method allows for rapid adjustment of anesthetic depth, as the concentration of the gas can be quickly modified. The agents work by diffusing into the bloodstream through the alveoli in the lungs and affect the central nervous system to produce anesthesia.

Unlike intravenous medications, which are injected directly into the bloodstream, inhalation agents require a different delivery method, focusing on the respiratory system. They are not topical anesthetics, as these are applied directly to the skin rather than inhaled, nor are they oral medications, which are taken by mouth for various forms of pain management and do not typically provide the rapid onset of anesthesia required in surgical settings. Hence, the characterization of inhalation agents as gas anesthetics absorbed through breathing aligns precisely with their purpose and function in surgical anesthesia.