Mediastinal position and air-fluid height after pneumonectomy: the effect of the respiratory cycle.

After pneumonectomy, a shift of the mediastinum toward the nonoperated side may be the initial indicator of a postoperative problem such as empyema, bronchopleural fistula, esophageal-pleural fistula, hemothorax, or recurrent tumor. Postoperatively, a drop in the fluid level on the operated side may indicate a bronchopleural fistula or other fistulous connection. To assess the effect of the respiratory cycle on these two signs, 16 patients were studied with inspiration-expiration films. In every case the mediastinum shifted toward the normal side in expiration, and in no case did a fluid level change position by more than 5 mm with respiratory maneuvers. Therefore, the respiratory phase must be considered when assessing the significance of mediastinal shift after pneumonectomy.