Prolonged postoperative altered mental status after methylene blue infusion during parathyroidectomy: a case report and review of the literature.

Methylene blue (5 mg/kg) is routinely given at our institution during parathyroidectomy. The dye stains the parathyroid glands and helps in better surgical visualisation. The technique is generally considered to be safe except for causing pseudo-cyanosis. We report a case of a patient who had confusion, agitation and altered mental status during the early postoperative course probably secondary to methylene blue infusion.