At the end of anesthesia, nitrous oxide diffuses from the body back into the alveoli more rapidly than nitrogen diffuses from the alveolar gas into the body. This has the effect of lowering the oxygen concentration in the alveoli and may cause hypoxia (diffusion hypoxia). During recovery from nitrous oxide anesthesia, room air must be supplemented with oxygen to prevent this.
It is also known as Fink effect.
