| Complication | Description |
| Postoperative respiratory failure | Need for mechanical ventilation for greater than 48 h postoperatively or the need for reinstitution of mechanical or non-invasive ventilation after extubation. |
| Acute lung injury | (1) New or worsening hypoxaemia with a ratio of arterial oxygen to fraction of inspired oxygen ⩽300 mm Hg (ARDS <200 mm Hg) on 2 consecutive days, (2) new bilateral pulmonary infiltrates on 2 consecutive days, (3) no evidence of left atrial hypertension (pulmonary capillary wedge pressure ⩽18 mm Hg, when available).4 The diagnosis of ALI or ARDS was mandatory to persist for more than 24 h. |
| Hydrostatic pulmonary oedema | Radiographic (diffuse bilateral pulmonary infiltrates), haemodynamic (pulmonary artery occlusion pressure >18 mm Hg or echocardiographic evidence of left ventricular or right ventricular dysfunction and elevated ventricular filling pressures), laboratory (brain natriuretic peptide >350 pg/ml) and documented physical findings (gallop, jugular venous distension). |
| Pneumonia | (a) New or progressive pulmonary infiltrate or consolidation in the chest radiograph and one or more of the following: new onset of purulent sputum or change in the character of sputum, sputum cultures showing a respiratory pathogen, isolation of pathogen from specimen obtained by transtracheal aspirate or bronchial brushing/lavage. |
| (b) Three or more of the following: fever (temperature >101°F (38.5°C)), rales or rhonchi on chest auscultation, new onset of purulent sputum or change in the character of sputum, sputum cultures showing a respiratory pathogen, isolation of pathogen from specimen obtained by transtracheal aspirate or bronchial brushing/lavage. | |
| Atelectasis | Lobar or multilobar atelectasis on chest radiograph and requiring bronchoscopic intervention. |
| Pneumothorax | If newly present on chest radiograph and requiring chest tube placement. |
ALI, acute lung injury; ARDS, adult respiratory distress syndrome.