Ex Vivo Lung Perfusion

Abstract

There is a critical mismatch between the number of donor lungs available and the demand for lungs for transplantation. This has created unacceptably high waiting-list mortality for lung transplant recipients. Currently (2012) in the United Kingdom, there are 216 patients on the lung transplant waiting list and 17 on heart and lung transplant list. The waiting times for suitable lungs average 412 days, with an increasing mortality and morbidity among the patients on the lung transplant list. Ex vivo lung perfusion (EVLP) has emerged as a technique for the assessment, resuscitation, and potential repair of suboptimal donor lungs. This is a rapidly developing field with significant clinical implications. In this review article, we critically appraise the background developments that have led to our current clinical practice. In particular, we focus on the human and animal experience, the different perfusion-ventilation strategies, and the impact of different perfusates and leukocyte filters. Finally, we examine EVLP as a potential research tool. This will provide insight into EVLP and its future development in the field of clinical lung transplantation.

Prolonged EVLP Using OCS Lung

“…Ex vivo lung perfusion (EVLP) may increase donor yield by monitoring and reconditioning extended-criteria donor lungs. 1,2 However, the safety of extended preservation with EVLP is currently unknown.…”

“…However, injured lungs that require reconditioning may not be ready for transplant within this timeframe. 2 The current study evaluates three perfusates for 24H EVLP on OCS: RBCs without plasma, autologous whole donor blood, and acellular buffered dextran-albumin solution (BDAS). It demonstrates that the safe interval for extended preservation of swine lungs is longer than that currently in use for human lung transplantation.…”

Recipient-matching of Passenger Leukocytes Prolongs Survival of Donor Lung Allografts in Miniature Swine

“…Using a different approach, kidney donors have been pre-treated with immunomodulatory drugs such as methotrexate, with mixed results on 5-year graft survival (36–39). The emerging use of ex-vivo lung perfusion circuits, which can facilitate both mechanical and pharmacologic leukocyte depletion, may improve lung allograft survival by reducing the passenger leukocyte load; and recent studies have demonstrated successful removal of passenger leukocytes from human lung allografts (40,41). …”

Engineering a microcirculation for perfusion control of ex vivo–assembled organ systems: Challenges and opportunities

“… 7 During this assessment period, organs can be resuscitated and potentially repaired if once deemed suboptimal for transplantation. Since there is a huge difference between the demand for organs for transplantation and the number of donor organs available, 8 increasing the number of donor organs available via ex vivo perfusion can go a long way in decreasing the transplantation waiting list mortality rates. The understanding of organ perfusion has only been possible by observing the potential effects of hypoxic injury on donated organs.…”

“…Specifically, for SCS, the organs are then immersed in fresh sterile solutions, double-bagged, and buried in melting ice in transport containers. 8 …”