Introduction: Organ Care System (OCS) Liver is a portable ex-vivo normothermic liver perfusion device recently shown to provide superior donor organ preservation. The impact of OCS Liver on post-reperfusion syndrome (PRS) remains unknown.

Method: This was a retrospective, single center, case-control study. All transplants utilizing OCS Liver between 1/1/2018 and 12/31/2020 were compared with a propensity score matched (PSM) cohort . The control population was matched for age, MELD, donor type and ventilator/circulatory support. Multiorgan transplants were excluded from the analysis. Donor, procurement, and recipient characteristics were collected for all recipients. Anesthesia records containing vitals by minute and pressor/inotropes were collected to establish baseline (5 minutes prior to reperfusion) and up to 30 minutes post-reperfusion hemodynamics.

Results: Following PSM there were 97 liver transplants in the study cohort, including 38 OCS (39%) and 59 controls (61%). Donor and recipient characteristics confirmed these groups were well matched. PRS, defined by ≥1 minute of mean arterial pressure 30% below baseline, was significantly reduced in the OCS group (1/38(3%) vs. 14/45(24%), p=0.005). OCS patients required significantly less post-reperfusion support, where both total norepinephrine (64 μg vs. 100 μg, p=0.02) and total epinephrine (18 μg vs. 38 μg, p=0.02) infusions were reduced compared to controls. Patients with combined blood pressure instability and pressor support were more likely to develop early allograft dysfunction (EAD), (15/56(27%) vs. 0/38(0%), p=0.001). However, the use of OCS was associated with a 10-fold reduction in EAD (1/38(2.6%) vs. 14/56(25%), p=0.004).

Conclusion: Normothermic machine perfusion using OCS Liver reduces hemodynamic instability after reperfusion and also results in a significantly reduced incidence of EAD.