228 Therapeutic Effect of Surfactant Inhalation on Lungs Donated after Cardiac Death in a Canine Lung Transplantation Model
Purpose: In lung transplantation, donation after cardiac death (DCD) has been introduced worldwide. To date, several programs have reported acceptable outcomes; however, the number of patients on waiting lists is indeed much more than that of the donated organs. Therefore, we considered the effective use of marginal donor grafts from uncontrolled DCD donors by investigating the effect of surfactant inhalation against pulmonary ischemia-reperfusion injury in canine lungs from DCD donors. Methods and Materials: Donor dogs were rendered cardiac-dead and left at room temperature. Following cardiac arrest for 240 min, ventilation with 100% oxygen was performed for 60 min. The dogs were allocated into two groups: The NS group (n 7) received aerosolized normal saline and the SF group (n 5) received aerosolized surfactant during the 60 min of ventilation. Thereafter the recipient dogs underwent single left lung transplantation. The right main pulmonary artery was ligated at 45 min after reperfusion to evaluate the functions of the transplanted left lung for 240 min after the reperfusion. Results: In the NS group, two animals died of severe pulmonary edema at 75 min of reperfusion, while in the SF group, all 5 animals survived for 240 min after reperfusion. At the end of reperfusion, surfactant inhalation significantly increased dynamic compliance (p 0.001), oxygenation (p 0.01), and inhibited pulmonary edema (p 0.01). Surfactant inhalation effectively increased lung tissue levels of ATP and ADP (ATP, ADP: p 0.05), and also decreased IL-8 and TNF-alpha in bronchoalveolar lavage fluid (IL-8: p 0.01, TNF-alpha: p 0.05). Histologically, lungs in the SF group showed fewer signs of interstitial edema and hemorrhage, and less neutrophilic infiltration than those in the NS group. Conclusions: Our results confirmed that surfactant inhalation in the last phase of warm ischemia prevented ischemia-reperfusion injury. This method may contribute to improve the graft function from DCD donors and to expand the donor pool.