For investigators

Information for investigators around trial design, criteria and outcomes.

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Study hypothesis

Does the availability of normothermic machine perfusion in extended criteria livers improve utilisation without compromising outcome?

Eligibility criteria

Participant inclusion criteria 

Liver offers:

  • Deceased organ donors aged 16 years or over
  • Offered through the national offering scheme
  • Donor Utilisation Index (DUI) greater than 0.27

Livers undergoing normothermic regional perfusion (NRP) will be included in the study and use of NRP corrected for in analysis.

Liver transplant recipients:

  • Recipients 18 years of age or above
  • Elective and super-urgent
  • Participant is willing and able to give informed consent for participation in the study

Participant exclusion criteria

Liver offers:

  • Donors falling outside national offering scheme
  • Donors where information about study participation was not sent with the organ offer
  • Donors from outside of the UK
  • Donor is HIV or hepatitis C positive
  • Livers undergoing any other form of ex-vivo machine preservation
  • Participating centre cannot offer NMP due to device, logistical or staffing reasons

Liver transplant recipients:

  • Receipt of a liver that has not been recruited to the study
  • Have not agreed to use of NMP according to local consent policy
  • Receipt of a split liver transplant
  • Receipt of a multi-organ transplant
  • Transplanted outside of the 7 participating centres

Study Design

The PLUS study has a threshold-crossing design with a prospectively-defined efficacy threshold.

A real-world control cohort identified from the NHS Blood and Transplant registry, meeting study inclusion criteria in which normothermic machine perfusion (NMP) was not used.

A study cohort of prospectively identified, consecutive liver offers with a donor utilisation index >0.27* in which NMP is made available.

*A DUI of >0.27 represents the 60% least well utilised livers

Study outcomes

Primary outcome measure

Functional utilisation – transplantation of the liver with 12-month patient and graft survival

Secondary outcome measures

  • Intervention costs, NHS resource use and quality of life
  • Biochemical liver function
  • Graft and patient survival
  • Postoperative hospital resource
  • Perfusion parameters, biomarkers in perfusion fluids and graft histology
  • Safety outcomes

For more information about the study please contact our team at