Two-layer method (UW solution/perfluorochemical plus O2) for lung preservation in rat lung transplantation

A new preservation method using perfluorochemicals (PFC) with oxygen administered continuously was developed for lung preservation and compared with traditional cold preservation methods for rat lung transplantation. Male Sprague-Dawley rats underwent orthotopic left lung transplantations of grafts preserved in lactiated Ringers solution (LR), University of Wisconsin solution (UW), Celsior solution, or a two-layer (PFC plus O2) solution for 6 hours. One hour after reperfusion, the right pulmonary artery and bronchus were clamped and 5 minutes later we recorded peak airway pressure and PaO2 level. The isograft was excised for measurement of myeloperoxidase activity, wet-to-dry ratio, and histologic examination to evaluate isograft function. The mean peak airway pressure was 29.80+/-6.72 mm H2O in the LR group, 28.80+/-5.76 mm H2O in the UW group, 33.60+/-5.17 mm H2O in the Celsior group, and 32.40+/-2.60 in the two-layer group. The mean PaO2 level was 99.78+/-76.09 mm Hg in the LR group, 87.84+/-33.58 mm Hg in the UW group, 104.50+/-72.93 mm Hg in the Celsior group, and 62.08+/-31.34 mm Hg in PFC and UW solution plus O2 group (two layers). The mean net myeloperoxidase activity OD level was 0.110+/-0.104 in the LR group, 0.392+/-0.328 in the UW group, 0.351+/-0.620 in the Celsior group, and 0.532+/-0.616 in the two-layer group. The mean wet-to-dry ratio was 7.47+/-1.60 in the LR group, 6.56+/-0.62 in the UW group, 7.54+/-2.19 in the Celsior group, and 5.32+/-2.20 in the two-layer group. The differences between groups in these parameters were not significant. Upon histologic examination, more inflammatory cell aggregates were seen in the two-layer group, less in the LR and the Celsior groups. The function of the lung graft after 6 hours of storage was not better using this two-layer method for preservation than traditional preservation methods in rat lung transplantation. Histologic examination revealed more inflammatory cell aggregates in the lung graft preserved using a two-layer method.