Lung recruitment after cardiac arrest during procurement of atelectatic donor lungs is a protective measure in lung transplantation

Background: Brain-dead donors are susceptible to pulmonary atelectasis (AT). In procurement surgery, lung recruitment under circulatory conditions and cold-flushing for atelectatic donor lungs often provoke graft injury due to the acute blood inflow. We hypothesized that lung recruitment without blood circulation can mitigate graft injury. This study aimed to examine the benefits of lung recruitment subsequent to cardiac arrest using a porcine lung-transplant model. Methods: Thirteen donor pigs were categorized into the non-atelectatic (No-AT) group (n=3) representing a healthy control group; AT-BCR group (n=5), in which AT was reverted by conventional blood-circulated recruitment (BCR); and AT-no-BCR group (n=5), in which AT was reverted by no-BCR following circulatory arrest. In the atelectatic donor models, the left main bronchus was ligated for 24 hours prior to lung procurement. Left lung transplantation (LTx) was subsequently performed in the thirteen recipient pigs. After 6 hours evaluation, the recipients were euthanized and the lung grafts were excised. Results: The post-transplant PaO₂/FiO₂ ratio was significantly higher in the AT-no-BCR group than in the AT-BCR group (P=0.015). Wet/dry ratio, histological findings of graft injury and tissue interleukin-8 expression in the AT-no-BCR group were similar to those of the No-AT group. Conclusions: Lung recruitment without circulation after circulatory arrest could be more protective for atelectatic donor lung than the conventional procedure.