A Rare Case of Iatrogenic Hemothorax Following Thoracentesis Secondary to an Aberrant Posterior Intercostal Artery

Iatrogenic hemothorax postthoracentesis is a rare procedural complication for experienced clinicians who use appropriate image‐guided techniques. Thoracentesis can lead to laceration of posterior intercostal arteries causing blood to fill the pleural space. Consequently, this can produce signs of a pleural effusion as well as vital sign instability, which can be fatal for patients and often require immediate intervention. Treatment options range from chest tube drainage to performing arterial embolization or, in severe cases, exploratory thoracotomy. Here, we display a case in which a 79‐year‐old female presents with a previously undocumented anatomic variant of the posterior intercostal artery in which the aberrant branch of the left ninth intercostal artery courses along the superior margin of the 10th rib. The patient experiences a nearly fatal hemothorax from an appropriately performed thoracentesis, necessitating a coil embolization.