Delirium is an acute organic brain syndrome of different physical and pathophysiological etiologies characterized by a disturbance in consciousness with accompanying change in cognition. Delirium causes prolonged length of stay in hospital and intensive care unit, also increased morbidity and mortality.

Thyroid storm is a severe, life-threatening type of thyrotoxicosis and is one of a few endocrine disorders that cause delirium. It is mostly occured suddenly after acute infection, surgical stress or trauma. This condition occurs due to excess production of thyroid hormone and 20-50% mortality rate depends on early diagnosis and treatment.

In this study it was aimed to present the diagnosis and treatment of a previously unknown hyperthyroid patient who underwent suspension laryngoscopy under general anesthesia and was post-operatively admitted to the intensive care unit because of pulmonary edema and proceeded to develop severe delirium caused by hyrotoxicosis.

Keywords: Thyroid storm, thyrotoxycosis, delirium, anesthesia, intensive care