The lungs of a brain dead multi organ donor will be retrieved according to standard protocol. Once a decision is made not to transplant the lungs either because of not satisfying ideal criteria or in the absence of a potential recipient they will be included in the study.They will be ventilated optimally and connected to a cardiopulmonary bypass machine for circulating preservative solution through it . Red blood cells will be added to the solution either initially or later depending on the group to which it is allocated .Monitoring of mechanical and gas exchange function and pathological examination of the lungs will be performed at various time points to observe the effect of red blood cells. The lungs will be properly discarded at the end of the procedure and will not be used for transplantation.