INTRODUCTION
In patients with end-stage lung disease awaiting lung transplantation (LTx), waiting list mortality remains high due to the shortage of available donor organs and the risk of acute respiratory failure in many patients on the transplant list. Recent reports have demonstrated that mechanically ventilated lung recipients have significantly higher post-transplant mortality when compared to non-ventilated recipients.1-3
Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is increasingly being used to bridge acutely deteriorating candidates to LTx as it can allow critically ill recipients to remain eligible for LTx while reducing pretransplant deconditioning.4-8 In particular, VV-ECMO as a bridge to transplantation (BTT) can facilitate early ambulation, thus improving their condition, and may mitigate detrimental intensive care unit (ICU) complications including weakness, delirium, and ventilator-associated pneumonia or lung injury.4 However, a decade ago few reports have raised skepticism for this strategy as they have suggested a negative effect of bridging with ECMO on post-transplant survival.2,9Since then, there is a growing evidence from high-volume and experienced lung transplant centers that BTT strategy using ECMO can provide satisfactory outcomes.10-14
In the present study, our aim was to analyze postoperative outcomes of patients on VV-ECMO as a BTT and the impact of preoperative VV-ECMO on posttransplant survival outcomes. Early and mid-term outcomes of BTT patients were evaluated and compared after matching with non-bridged LTx recipients. In order to achieve the best possible matching between both subgroups, we have performed optimal full matching based on Mahalanobis distance and sensitivity analysis.