Large Pleural Effusion Following CABG

Fig.1 Portable chest radiograph of a man right after CABG shows a small left pleural effusion with adjacent retrocardiac opacity (red stars). There is slight widening of the superior mediastinum. Findings could be seen in a patient following recent CABG. 
Fig. 2 Portable chest radiograph at 24 hours following CABG shows interval marked increase in a large left pleural effusion (red/blue arrows) occupying nearly the whole left hemithorax. There is slight mediastinal shift to the right, which has progressed. The patient had increased dyspnea with dropped hematocrit. 

Points

• Major differential diagnoses of interval increased opacity after surgery are pleural effusion (hemothorax), atelectasis and pneumonia (aspiration)
  
• Key to differentiate those diagnoses is to look at serial radiographs, lung volumes, and mediastinal shift.
• Large, early (<30>

Reference:

Light R. Pleural effusions after coronary artery bypass graft surgery. Curr Opin Pulm Med 2002 (July)