all sorts of molecules are exhaled from your lungs, and there is a degree of equilibrium between those molecules in your bloodstream and your exhaled breath. when we exhale those molecules, we can smell them and there are many molecules that are exhaled under anesthesia when you are having surgery, including anesthetics, local anesthetics, medications for your heart, anti-nausea medications, medications for pain, and many more. many of these medications can have a particular smell depending on how awake you are to notice them!
