For investigators
Information for investigators around trial design, criteria and outcomes.

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 PLUS@nhsbt.nhs.uk.