Harlequin Syndrome Related to Perioperative Intercostal Blockade: A Case Report.

Harlequin syndrome is a rare syndrome characterized by hemifacial flushing and altered facial sweating, with only a few case reports related to intercostal blockades. We present a case of Harlequin syndrome in a 65-year-old woman after intercostal blockade for video-assisted thoracoscopic lobectomy. One hour postoperatively, the patient became nauseated and presented with flushing of the right half of the face with a clear line of demarcation.