Zhong 2017

Methods	Study design: parallel RCT Duration of study: July 2010 to July 2015 Duration of follow‐up: 3 years
Participants	Country: China Setting: not reported Donor characteristics Mean age ± SD: 32.8 ± 12.4 years Number of DCD: 153 (282 kidneys) Sex (M/F): 107/61 Inclusion criteria: DCD donors which where Maastricht category III; organ donors had to be at least 16 years of age Exclusion criteria: not reported. Recipient characteristics Inclusion criteria: first time kidney transplants Exclusion criteria: received the kidney with another organ Sex (M/F): MP group (79/62); SCS group (73/68) Mean age ± SD (years): MP group (41.4 ± 11.6); SCS group (40.6 ± 9.3)
Interventions	Machine perfusion LifePort kidney transporter machines (ORS) with a constant pressure of 30 mmHg and temperature of 0°C to 4°C was used for HMP using KPS‐1 Static cold storage UW solution Mean CIT Not significantly different between groups: 11.8 (6.3 to 22.5) hours in the SCS group and 10.3 (5.1 to 24.0) hours in the MP group (P = 0.063)
Outcomes	DGF Functional DGF: defined by the absence of a decrease in the SCr level of at least 10% per day for at least three consecutive days within the first week after transplantation One and 3‐year graft survival Median SCr and median urine output each day of the first week post‐transplant Resistance in renal arteries using Doppler ultrasound within 48 hours post‐transplant
Notes	One kidney from each pair assigned to MP and the other to SCS 282 kidneys from 153 donors. All donors were DCD Doppler USS was used to assess arterial resistance in the renal vasculature within 48 hours post ‐transplant. As arterial resistance was significantly lower in the HMP group, the authors concluded that part of the beneficial effect of HMP is due to decreased vasospasm Funding source: No conflict of interest. Funding was from the State Key Program of National Natural Science of China, No: U1403222; Special Foundation of Basic Research for the Central Universities, No: 2042014kf0101
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	No specific information on random sequence generation, but all consecutive donors were assessed for inclusion, and valid reasons were given for any excluded donors
Allocation concealment (selection bias)	Low risk	No specific information on allocation concealment but all consecutive donors were assessed for inclusion, and valid reasons were given for any excluded donors
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Transplanting teams were blinded to the perfusion parameter readings. Transplant teams were not blinded to the storage method used but this is unlikely to affect the outcome, especially as there was no difference in CIT between the groups
Blinding of outcome assessment (detection bias) All outcomes	Low risk	No blinding, but outcome measurements are unlikely to be affected by the lack of blinding
Incomplete outcome data (attrition bias) All outcomes	Low risk	Full follow‐up was reported for all participants
Selective reporting (reporting bias)	Low risk	Outcomes suitable, with adequate reporting
Other bias	Low risk	No kidneys were swapped between groups. An independent scientific steering committee composed of clinicians and scientists was solely responsible for the design, conduct, data analysis, and manuscript preparation

ATN ‐ acute tubular necrosis; CCD ‐ cardiocirculatory death; CIT ‐ cold ischaemic time; CrCl ‐ creatinine clearance; DBD ‐ donor after brainstem death; DCD ‐ donor after circulatory death; ECD ‐ extended/expanded criteria donor; ICU ‐ intensive care unit; MP ‐ machine perfusion; PNF ‐ primary non‐function; SCr ‐ serum creatinine; SCS ‐ static cold storage