The patient was extubated on the day of surgery. No respiratory, circulatory, or infectious complications occurred, but renal failure developed gradually, the suspected cause being intraoperative hypotension. No nausea or vomiting was noted. NIPPV was started via a facemask on day 4 because this morbidly obese patient (122 kg) could not be weaned from nasal oxygen and had persistent moderate hypoxemia with persistent basal atelectasis on the chest radiograph. NIPPV was initiated with a fraction of inspired oxygen of 0.5, a positive end-expiratory pressure of 5 cm H2O, and a pressure-support level of 15 cm H2O. When NIPPV was stopped after 1 h, the hypoxemia worsened, and marked tachypnea with agitation developed. NIPPV was immediately restarted and the pulse oximetric saturation dropped to 97%. After an additional 2 h of NIPPV, hypotension and loss of consciousness occurred, requiring orotracheal intubation, mechanical ventilation, and vasoactive drug therapy. The postintubation chest radiograph disclosed left-sided hydropneumothorax, which was confirmed by CT. A chest tube was inserted, and 1,000 mL of gastric-like fluid was recovered. A left thoracotomy was performed, and a 3-cm linear tear was seen in the lower esophagus. The tear was sutured, drains were placed in the pleural cavity and mediastinum, and a discharge gastrostomy was performed with a jejunostomy for enteral nutrition.