The use of postoperative X-ray to evaluate residual pleural space and predict infectious pleuropulmonary complications after lung resection for infectious disease.

BACKGROUND: Postoperative residual pleural space (RPS) is a critical point in the evaluation of patients undergoing pulmonary resection by infectious pulmonary diseases. This study aims to correlate its incidence, and size, with the risk to develop infectious pleuropulmonary complications.

METHODS: Retrospective cohort of patients undergoing non-pneumonectomy resection due to infectious lung disease. Two thoracic surgeons analyzed the radiographs systematically. The assessment consisted of defining the presence of a postoperative RPS, and its area calculation the ratio between the area of the complete pleural cavity. These measures were used to predict the risk for infectious pleuropulmonary complications in the first 30 postoperative days.

RESULTS: From the total of 135 patients 37.7% had tuberculosis. On the 4postoperative chest X-ray, 76 (58%) presented RPS. Those patients had an increased risk [risk ratio (RR) =1.47; 95% confidence interval (CI): 1.12-1.92; P=0.01] to develop infectious pleuropulmonary complications. For empyema only the risk was 3.68 (95% CI: 1.12-12.11; P=0.01). In the subgroup with a cavity ratio ≥20%, it was greater: 6.2 (95% CI: 2.7-14.4; P=0.001) for empyema, 2.24 (95% CI: 1.3-4.9; P=0.043) for pneumonia. The multivariate analysis showed a hazard ratio of 6.24 (95% CI: 1.95-19.93; P=0.002) for the development of empyema.

CONCLUSIONS: This study demonstrates the applicability of a simple and accessible methodology in the measurement of postoperative RPS. Their results proved its relation to a greater chance of developing infectious pleuropulmonary complications.