[Facial paralysis after non-otologic surgery under general anesthesia].

Peripheral facial palsy is rare after non-otological surgery under general anesthesia. The condition generally is attributed to damage produced by endotracheal intubation maneuvers in patients with anatomic variants of the facial nerve. We report three cases of facial palsy which occurred after abdominal surgery. In every case, nitrous oxide gas was used in anesthesia. One patient had intubation via tracheostomy; all the patients had endocranial facial symptoms and a history of previous surgery. The diversity of these factors suggests that other mechanisms of production aside from damage produced by endotracheal intubation should be considered. The use of nitrous oxide increases middle ear pressure and could produce focal nerve compression. This does not invalidate earlier hypotheses, but does clarify pathophysiological concepts of this condition.