Background: Demand for liver transplant remains high, with waiting list mortality of 20-40%. In the United Kingdom the National Liver Offering Scheme (NLOS) disadvantages high-risk candidates; some never receive offers whilst 25% of retrieved organs are discarded nationally. We introduced Normothermic mAchine Perfusion of the Liver to Enable the high risk recipientS (NAPLES)  project to use marginal grafts using Normothermic Machine Perfusion (NMP) to serve high-risk candidates. We report early outcomes using marginal Donation after Brainstem Death (DBD) grafts that would otherwise be declined for high risk recipients.
Methods: Prospective data of preliminary analysis of first 14months since the project started.  Patients were consented to receive a marginal NLOS or fast-track (FT) DBD liver after NMP.  Back-to-base NMP was performed and the organ transplanted if previously defined Birmingham viability criteria were fulfilled. Data is reported as median (range) where applicable.
Results: 35 DBD livers were included in NAPLES project [median donor age 51 (29-78) years], median BMI 27 (17-40), 25/35 grafts (71%) were steatotic (>moderate steatosis; n=15). Median CIT was 380 (127-709) min, and median DRI was 1.71 (1.28-2.74). After a median of 720 min of perfusion time, 26 grafts fulfilled criteria for transplantation (72%). Median recipient age was 45 years (18-69). The majority (58%) were re-transplants with median UKELD 57 (46-66). Median operative time was 895 min (251-800). Median Peak ALT post-transplant was 545 IU/L (160-2452) with median ITU stay was 5.5 days. There was no primary non-function, 23% of Clavien-Dindo 3-4 morbidity was observed, and 9 patients (34%) required post op renal support. Median LOS was 17 days. There was 100% patient survival in 90-days and until last follow up only 2 patients (7.6%) have required re-transplantation.
Conclusions: The use of NMP has allowed safe transplantation of marginal liver grafts into high risk patients, with no mortality and 7.6% graft loss.