Primary graft failure of a transplanted lung may be due to donor, recipient, or surgical factors. Ischemia-reperfusion injury with activation of recipient innate immunity usually occurring within 72 hours status post-lung transplant is a major cause of early primary graft failure. The injury may resolve or may result in adult respiratory distress syndrome. Prolonged donor organ preservation under anoxic conditions is thought to be the cause. Improvement in organ preservation techniques and perservative solutions has lowered the incidence rate. No correlation has been found with age, sex, or single versus double lung transplantation.