Anosmia after general anaesthesia: a case report.

Although anaesthetic drugs are included among the aetiological factors of anosmia, limited reports exist of anosmia induced by general anaesthesia. We present the case of a 60-year-old female patient with a 3-month history of altered smell and taste immediately after recovery from general anaesthesia for a urological operation. The anaesthetic drugs used were fentanyl, propofol and sevoflurane. Clinical examination and a computed tomography brain scan did not reveal any pathology. Psychophysical testing showed anosmia and normal taste function. Imaging studies using single photon emission computed tomography of the brain were performed twice: as a baseline examination; and after odour stimulation with phenyl ethyl alcohol. Normal brain activity without reaction to odorous stimuli suggested peripheral dysfunction or stimuli transmission problems. The patient, after four months of olfactory retraining, demonstrated significant improvement. The onset of the dysfunction in relation with the imaging findings may imply that anaesthetics could induce the olfactory dysfunction.