Pentoxifylline and Lung Ischemia—Reperfusion Injury

Summary Pentoxifylline (PTX) attenuates neutrophil-mediated lung injury in several models of acute lung inflammation. Because pulmonary neutrophil sequestration is the main determinant of ischemia-reperfusion (IR) injury in lung transplantation, we sought to determine whether or not PTX prevented IR injury in isolated perfused rat and rabbit lungs submitted to IR, and in pigs after left lung allotransplantation. In rat lungs after IR, the coefficient of lung endothelial permeability (Kfc) increased by 112 ± 12% in controls and by 27 ± 8% (p < 0.001) in PTX-treated lungs. After IR, lung myeloperoxidase and blood neutrophil count decrease were lower with PTX than in controls, and the changes in Kfc were correlated with the percentage decrease in blood neutrophils during reperfusion. In rabbit lungs, endothelium-dependent relaxation in isolated pulmonary arterial rings was decreased in the control group and normal in the PTX group. In pigs ventilated with pure oxygen, the PaO2 was greater in the PTX group than in the control group (423 ± 49 vs. 265 ± 43 mm Hg; p < 0.05), whereas the total pulmonary vascular resistance was lower (15 ± 1 vs. 30 ± 9 mm Hg/L/min; p < 0.02). After reperfusion, the decrease in circulating leukocyte count fell by 35 ± 3% in the control group and remained unchanged in the PTX group, and the leukocyte count per microscopic field in the transplanted lung was lower in the PTX group than in the control group (p < 0.02). In conclusion, PTX prevented IR lung endothelium injury and improved post-IR lung function by decreasing neutrophil lung sequestration, and this agent might be useful in clinical lung transplantation.