Pleural effusions following lung transplantation. Time course, characteristics, and clinical implications.

The time course and characteristics of ipsilateral pleural effusion in nine consecutive single lung transplant recipients are described and compared with those of six patients who underwent other cardiothoracic operations. Ipsilateral pleural fluid occurs in all lung transplant recipients, beginning immediately following transplantation and continuing for up to 9 days. Pleural fluid immediately after lung transplantation is bloody, exudative, and neutrophil predominant, which is similar to the characteristics of pleural fluid following other cardiothoracic surgery. Pleural fluid cellularity, lactate dehydrogenase, and total protein content decrease rapidly over the first week in lung transplant recipients. The percentage of neutrophils decreases from 90 to 50% by day 7. Pleural fluid output in lung transplant recipients declines steadily during the first week and is minimal by day 9. Pleural fluid output declines more rapidly in patients who have undergone cardiothoracic surgery than in the lung transplant recipients. An early rise in pleural fluid output may reflect the development of posttransplant pulmonary edema. We conclude that it is unnecessary to analyze pleural fluid after lung transplantation if the pleural fluid output is decreasing and the clinical course is appropriate.