Univariate analysis showed that male gender, diabetes, pleuritic symptoms, white blood cells >10×109/L, albumin level <25 g/L, and positive sputum cultures were potential clinical-related risk factors and that an abscess >5 cm in diameter and transpulmonary fissure abscesses were potential computed tomography imaging-related risk factors for pulmonary abscess-related empyema.
We also analysed other risk factors for postoperative complications, such as patient age, previous surgeries, preoperative C-reactive protein, faecal calprotectin, albumin and haemoglobin levels, American Society of Anesthesiologists (ASA) classification, preoperative immunosuppressive medication, surgical approach and the presence of intraoperative fistula or abscess.