Major increase in the proportion of donor lungs transplanted after ex-vivo lung perfusion

Over the last decade, an average of one in four lung transplants in Toronto were derived from EVLP-treated marginal lungs. This proportion has increased successively each year until close to half of all lungs transplanted in Toronto last year, according to data published recently ⁽¹⁾⁽²⁾. Despite this expansion in the use of ex vivo lung perfusion (EVLP), long-term outcomes from EVLP-treated lungs have remained comparable to those of standard non-EVLP lungs.

In terms of utilization (conversion) rates of lungs subjected to ex-vivo perfusion, a more detailed breakdown within the Toronto data indicates that about 70% of marginal lungs subjected to EVLP were accepted for transplantation ⁽²⁾. Conversion rates were fairly similar for all categories of donor lungs: 63% of high-risk lungs donated after circulatory death (DCD) were accepted;70% of high-risk lungs donated after brain death (DBD) were accepted; nearly 80% of standard risk DCDs and of those with prolonged preservation times were accepted. There were no differences in survival rates or in mechanical ventilation, intensive care unit stay, and hospital stay – and no differences in recipient age or pre-transplant diagnosis.

These EVLP conversion / utilization rates from Toronto roughly reflect those of other major lung centers, although, of course, conversion rates partially reflect the relative DCD / DBD mix and local selection of marginal donors. A recent meta-analysis ⁽³⁾ of 20 published studies on circa 2570 EVLP procedures reported conversion rates ranging from 34% to 100%, with the vast majority (17 of 20 centers) exceeding 70%. 18 of the 20 studies involved static EVLP and Steen solution as the perfusate. The authors concluded that EVLP, “not only increased the utilization of marginal donors, but also could extend preservation time and reduce the total ischemia time of donor grafts.”

References:

1. Divithotawela C et al, Long-term Outcomes of Lung Transplant With Ex Vivo Lung Perfusion. JAMA Surg. 2019 Oct 9. doi: 10.1001/jamasurg.2019.4079. [Epub ahead of print] (link to abstract)  

2. Cypel M et al, Normothermic ex vivo lung perfusion. Does the indication impact organ utilization and patient outcomes after transplantation? (Toronto ) J Thorac Cardiovasc Surg. 2019 Sep 9. pii: S0022-5223(19)31732-5. doi: 10.1016/j.jtcvs.2019.06.123. [Epub ahead of print] (link to abstract)

3. Luo Q et al, The Conversional Efficacy of Ex Vivo Lung Perfusion and Clinical Outcomes in Patients Undergoing Transplantation of Donor Lungs by Ex Vivo Lung Perfusion: A Meta-Analysis. (Hangzhou) Ann Transplant. 2019 Dec 27;24:647-660. doi: 10.12659/AOT.919242. (link to abstract)  

Xvivo Insights PB-2020-02-27