Case Report: Perioperative acquired long QT syndrome secondary to severe hypokalemia from duodenal foreign body obstruction in a toddler

This case report describes the perioperative anesthetic management of a 14-months-old male toddler who developed acquired long QT syndrome (aLQTS) secondary to severe hypokalemia resulting from duodenal foreign body obstruction. Intensive intravenous potassium supplementation and prophylactic magnesium sulfate administration were initiated to stabilize myocardial electrophysiology and reduce arrhythmic risk. The patient subsequently underwent successful surgical removal of the obstructing foreign body. Postoperatively, electrolyte levels normalized, and the QT interval returned to baseline. This case highlights the critical importance of vigilance for aLQTS and the risk of malignant arrhythmias in toddlers presenting with severe vomiting and hypokalemia. Early recognition and synergistic intervention are key to preventing torsades de pointes (TdP).