Effect of lung resection on pleuro-pulmonary mechanics and fluid balance

• We evaluated in patients the effect of lung resection on pleuro-pulmonary mechanics and fluid balance.
• The decrease in lung compliance following resection exceeded that expected from resected mass suggesting a perturbation in lung fluid balance.
• An inverse relationship was found between total pleural fluid drained and the decrease in lung compliance.
• We hypothesized that lung overdistension on re-expansion in the chest is causative to a perturbation in the pleuro-pulmonary fluid balance.

The aim of the study was to determine in human patients the effect of lung resection on lung compliance and on pleuro-pulmonary fluid balance. Pre and post-operative values of compliance were measured in anesthetized patients undergoing resection for lung cancer (N = 11) through double-lumen bronchial intubation. Lung compliance was measured for 10–12 cm H2O increase in alveolar pressure from 5 cm H2O PEEP in control and repeated after resection. No air leak was assessed and pleural fluid was collected during hospital stay. A significant negative correlation (r2 = 0.68) was found between compliance at 10 min and resected mass. Based on the pre-operative estimated lung weight, the decrease in compliance following lung resection exceeded by 10–15% that expected from resected mass. Significant negative relationships were found by relating pleural fluid drainage flow to the remaining lung mass and to post-operative lung compliance. Following lung re-expansion, data suggest a causative relationship between the decrease in compliance and the perturbation in pleuro-pulmonary fluid balance.