Re-expansion pulmonary oedema may occur after chest tube drainage of pneumothorax and can give rise to cardiopulmonary manifestations which range from the mild to the severe. In order to evaluate the prevalence and the clinical manifestations of this complication, all patients with spontaneous pneumothorax managed with chest tube drainage were evaluated over an 8-yr period (1986-1994). A chest radiograph was performed routinely in all patients within 4 h of tube insertion. Lung expansion and the appearance of infiltrates within the lungs were investigated specifically. Re-expansion oedema was noted in three of 320 episodes (0.9%). Two of the three patients needed rapid and extensive clinical treatment.