[A case of re-expansion pulmonary edema following water seal drainage for spontaneous pneumothorax--management with right and left-separated mechanical ventilation].

A 23-year-old male with complete collapse of the right lung due to spontaneous pneumothorax was admitted 11 days after its onset. Paying close attention to the re-expansion pulmonary edema (REPE), water seal drainage was performed. Following couple episodes of persistent severe cough, four hours later, he developed dyspnea and began to expectorate frothy massive sputum. Chest X-ray revealed pulmonary edema of the entire right lung field. Measurement of total proteins and neutrophil elastase in airway exudates showed 5.5 g/dl (ratio to plasma, 0.89) and 7000 micrograms/l, respectively. Because of marked difference of compliance between bilateral lungs, management with right and left-separated mechanical ventilation and PEEP applied only to the right lung was performed. Although transient mediastinal deviation to the left was observed, successful management was achieved by the maneuver. High concentrations of total proteins and neutrophil elastase in edema fluid suggest that increased vascular permeability due to endothelial cell injury via activated neutrophils is mainly responsible for REPE. In the present case, rapid expansion of the collapsed lung accelerated by severe cough seems to be a predisposing factor of REPE. In patient with prolonged pneumothorax, suppression of cough is thought to be important for the prevention of REPE even with water seal drainage.