The FGF, DEL, ... command on the Anesthesia menu invokes a dialog box which allows you to change Fresh Gas Flow (FGF), vaporizer setting (DEL), Alveolar Ventilation (VA), and Cardiac Output (CO) for the simulation in the currently active simulation window.
The vaporizer setting (DEL) differs from most of the other settings: it doesn't necessarily change all the views to match. The anesthetic whose setting is changed is either
See Multiple Agent Simulations for an explanation.