Effects of the duration of bridge to lung transplantation with extracorporeal membrane oxygenation

BACKGROUND: Although bridge to lung transplantation (BTT) with extracorporeal membrane oxygenation (ECMO) is increasingly performed, the impact of BTT and its duration on post-transplant outcomes are unclear. METHODS: We retrospectively reviewed medical records of adult patients who underwent lung or heart-lung transplantation in our institution between January 2008 and December 2018. Data were compared in patients who did (n = 41; BTT) and did not (n = 36; non-BTT) require pre-transplant ECMO support. Data were also compared in patients who underwent short-term (<14 days; n = 21; ST-BTT) and long-term (≥14 days; n = 20; LT-BTT) BTTs. RESULTS: Among 77 patients included, 51 (66.2%) were male and median age was 53 years. The median bridging time in the BTT group was 13 days (interquartile range [IQR], 7–19 days). Although simplified acute physiologic score II was significantly higher in the BTT group (median, 35; IQR, 31–49 in BTT group vs. median, 12; IQR, 7–19 in non-BTT group; p<0.001), 1-year (73.2% vs. 80.6%; p = 0.361) and 5-year (61.5% vs. 61.5%; p = 0.765) post-transplant survival rates were comparable in both groups. Comparison of ST- and LT-BTT subgroups showed that 1-year (90.5% vs. 55.0%; p = 0.009) and 5-year (73.0% vs. 48.1%; p = 0.030) post-transplant survival rates were significantly higher in ST-BTT group. In age and sex adjusted model, the LT-BTT was an independent risk factor for 1-year post-transplant mortality (hazard ratio, 3.019; 95% confidence interval, 1.119–8.146; p = 0.029), whereas the ST-BTT was not. CONCLUSIONS: Despite the severe illness, the BTT group showed favorable post-transplantation outcomes, particularly those bridged for less than 14 days.