There is increasing evidence that oxygen derived free radicals are involved in the injury that occurs following the reperfusion of ischaemic tissue. Deferoxamine by preventing hydroxyl radical production and scavenging superoxide anion may attenuate this injury and its effects were evaluated following 4 hours of static hypothermic pulmonary preservation. Left lung autotransplantation was performed in 12 mongrel dogs. The autograft was initially flushed with 1000 cc of modified Collins solution and then stored in an inflated state for 4 hours in 4ºC saline. Six dogs received deferoxamine 500 mg intravenously infused before and immediately after the time of reperfusion. Following reimplantation, contralateral pulmonary artery ligation was performed and the animals were then maintained on a fixed FiO2 (40%) and monitored for 6 hours. During the first hour of reperfusion arterial pO2 was significantly better in the deferoxamine treated dogs (p < 0.05). Alveolar-arterial oxygen gradients were also lower (p < 0.05). Pulmonary vascular resistance was not different between groups. We conclude that deferoxamine improves gas exchange in the immediate reperfusion period and that further investigation of its use is warranted.
pulmonary preservation; free radicals