OLB was performed in an operating room or at the bedside in an ICU by an experienced thoracic surgeon. Bedside OLB was indicated when the FiO 2 used reached 1 with an applied positive end-expiratory pressure (PEEP) of at least 12 cmH 2 O. With regard to mechanical ventilator settings to prevent air leakage, PEEP was immediately reduced 2 cmH 2 O from the baseline level after surgery. Pulmonary tissue was harvested from a site considered new or from a progressive lesion identified by chest HRCT or chest X-ray.