Pleural effusions occur commonly in the immediate posttransplant period. As a consequence of the transplant procedure, the pulmonary lymphatics are severed, which reduces the ability to clear any fluid from the pleural space. Ongoing effusion might prolong the need for chest tube drainage postoperatively, but usually not beyond the first week or two. If the thoracic duct is severed, as can occur in patients with extensive mediastinal adhesions, then there is a risk of chylothorax, which should be considered for any persistent effusion. After the immediate posttransplant period, the occurrence of pleural effusions is usually in the context of other causes such as empyema, or as a manifestation of a parapneumonic process, heart failure, pulmonary embolism, acute rejection, or trapped lung.