Extracorporeal life support as bridge to lung transplantation: a systematic review

Abstract

IntroductionPatients with acute respiratory failure requiring respiratory support with invasive mechanical ventilation while awaiting lung transplantation are at a high risk of death. Extracorporeal membrane oxygenation (ECMO) has been proposed as an alternative bridging strategy to mechanical ventilation. The aim of this study was to assess the current evidence regarding how the ECMO bridge influences patients’ survival and length of hospital stay.MethodsWe performed a systematic review by searching PubMed, EMBASE and the bibliographies of retrieved articles. Three reviewers independently screened citation titles and abstracts and agreement was reached by consensus. We selected studies enrolling patients who received ECMO with the intention to bridge lung transplant. We included randomized controlled trials (RCTs), case–control studies and case series with ten or more patients. Outcomes of interest included survival and length of hospital stay. Quantitative data summaries were made when feasible.ResultsWe identified 82 studies, of which 14 were included in the final analysis. All 14 were retrospective studies which enrolled 441 patients in total. Because of the broad heterogeneity among the studies we did not perform a meta-analysis. The mortality rate of patients on ECMO before lung transplant and the one-year survival ranged from 10% to 50% and 50% to 90%, respectively. The intensive care and hospital length of stay ranged between a median of 15 to 47 days and 22 to 47 days, respectively. There was a general paucity of high-quality data and significant heterogeneity among studies in the enrolled patients and technology used, which confounded analysis.ConclusionsIn most of the studies, patients on ECMO while awaiting lung transplantation also received invasive mechanical ventilation. Therefore, whether ECMO as an alternative, rather than an adjunction, to invasive mechanical ventilation is a better bridging strategy to lung transplantation still remains an unresolved issue. ECMO support as a bridge for these patients could provide acceptable one-year survival. Future studies are needed to investigate ECMO as part of an algorithm of care for patients with end-stage lung disease.

Extracorporeal life support for adult cardiopulmonary failure

“…transplantation, but with the improved safety profile of modern ECMO, several groups have demonstrated excellent outcomes with the use of pre-transplant extracorporeal support [27][28][29][30][31]. In some circumstances, VV ECMO via a dual lumen cannula can provide sufficient gas exchange to allow for the removal of mechanical ventilatory support for patients awaiting lung transplantation.…”

The ICM research agenda on extracorporeal life support

“…More recent analyses using UNOS data from 2010 to 2015 showed that the adverse influence of ECMO was absent in high-volume lung transplant centers [61]. A systematic review including 14 retrospective studies pointed out that current data do not permit a definitive conclusion on the efficacy of ECMO as a bridge to transpla ntation [62]. However, these patients may have an acceptable 1-year survival [626364].…”

Selection of Patients for Initial Clinical Trials of Solid Organ Xenotransplantation

“…ECMO is a potentially life-saving therapy for patients with respiratory failure, 87–89 and has been successfully used as a bridge to lung allotransplantation in highly-selected patients. 87,88,90,91 However, in most series posttransplant survival is inversely correlated to duration of ECMO support 87,88 and timely access to successful lung xenografts might substantially shorten the duration of ECMO support and improve outcomes.…”

“…87,88,90,91 However, in most series posttransplant survival is inversely correlated to duration of ECMO support 87,88 and timely access to successful lung xenografts might substantially shorten the duration of ECMO support and improve outcomes.…”