Hypothermic Oxygenated (HOPE) Versus Normothermic Machine Perfusion (NMP) in Human Liver Transplantation

Summary

The common practice of conventional cold storage (CCS) organ preservation has changed little since the initial introduction of the original University of Wisconsin (UW) organ preservation solution in the late 1980s. CCS relies on hypothermia to decelerate metabolism and reduce oxygen demand in order to prolong the time of ischemia without rapid functional graft impairment, therefore merely delaying graft damage. While CCS only prolongs storage time and limits the damage sustained during the period of cold ischemia, ex-vivo machine perfusion (MP) appears to be capable of reversing some of these effects. Currently, two main paradigms prevail in the clinical approach to liver allograft MP: hypothermic oxygenated MP (HOPE) may be seen as a dynamic alternative of the traditional organ preservation based on hypothermia-induced deceleration of metabolism, which aims to combine the positive effects of hypothermia observed in classical cold storage (e.g. technical simplicity, relative safety, decreased metabolism) with the positive effects of dynamic preservation (e.g. controlled sheer stress mediated gene activation, removal of metabolites, transport of oxygen and ATP recharging). Normothermic perfusion (NMP) aims at re-equilibration of cellular metabolism by preserving the organ at physiological temperatures whilst ensuring sufficient oxygen and nutrient supply. In both approaches, the perpetual circulation and moderate shear-stress sustain endothelial functionality. While past and current clinical trials were designed to compare different MP approaches with CCS as the clinical standard, a direct comparison between different end-ischemic MP techniques (HOPE versus NMP) is still lacking. The purpose of this study is to test the effects of end-ischemic NMP versus end-ischemic HOPE technique in a multicentre prospective randomized controlled clinical trial (RCT) on ECD liver grafts in DBD liver-transplantation (HOPE-NMP). Two-hundred-thirteen (n = 213) human whole organ liver grafts will be submitted to either 4-24 hours of NMP (n = 85) or 2-3 hours of HOPE (n = 85) directly before implantation and going to be compared to a control-group of patients (n = 43) transplanted with static cold storage preserved ECD-allografts. Primary (surgical complications as assessed by the comprehensive complication index \[CCI\]) and secondary (among others laboratory values, graft- and patient survival, hospital costs, hospital stay) endpoints are going to be analysed.)

Conditions

• Hepatocellular Injury
• Liver Transplant Disorder

Interventions

DEVICE

Hypothermic oxygenated perfusion (HOPE)

HOPE for 1 hour via the portal vein in a recirculating and pressure controlled system (2-3 mm Hg), 0.1 ml/g liver/min, perfusion volume 3-4 L, Belzer (UW) machine perfusion solution, perfusate temperature 10 °C, perfusate oxygenation pO2 of 60-80 kPa

DEVICE

Normothermic machine perfusion (NMP)

End-ischemic NMP will be continued throughout the recipient hepatectomy and until the transplanting team is ready to implant the liver. The minimum protocol-stipulated NMP duration is 4 hours, the time needed for ATP repletion in animal studies. Total NMP preservation time will be according to the official recommendations of the manufacturer (4-24 hours) and at the discretion of the local transplant centre. The liver allograft will be disconnected from the OrganOx metra® device immediately prior to transplantation and flushed with three litres of HTK via the hepatic artery and the portal vein.

Sponsors & Collaborators

• Charite University, Berlin, Germany

  lead OTHER

Principal Investigators

• Georg Lurje, M.D. · Charite University, Berlin, Germany

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

75 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2021-01-14

Primary Completion

2023-12-31

Completion

2024-12-31

Countries

• Germany

Study Locations