Lung volume reduction surgery is intended to improve pulmonary function in selected patients with severe emphysema by improving diaphragmatic and chest wall mechanisms. An increasing body of scientific evidence demonstrates that lung volume reduction surgery provides significant palliation, with long-run benefits for at least two years. Measurements of pulmonary function have also confirmed significant improvement in objective physiologic parameters such as airway obstruction, elastic recoil, and gas exchange. However, some questions concerning these issues have not been answered yet: long-term efficacy, patient's outcome predictors, cost-benefit analyses, and clarification of the indication for different surgical approaches.

Keywords: Emphysema. Lung reduction surgery.

The ischemia-reperfusion injury is a common pathophysiologic phenomenon in many diseases seen in daily clinical practice. The lung can be affected both directly, as in pulmonary edema after lung transplant or after resolution of pulmonary thromboembolism, and indirectly, as in shock states or after reperfusion injury in distant organs as intestine or lower extremities. The latter situation can occur secondary to aortic occlusion for surgical procedures. Many mediators have been implicated in the ischemia-reperfusion injury: oxygen free radicals, lipid products as thromboxane, adhesion molecules involved in leukocyte-endothelial interaction, tumor necrosis factor, among others. Therapeutic strategies for the reperfusion injury are used only at the experimental level and in very few clinical studies. Antioxidants, inhibitors of lipid mediators and of the leukocyte-endothelial interaction and promoters of blood flow in post-ischemic vessels have been used.

Keywords: Lung. Injury. Reperfusion. Ischemia.