Rescue by Hypothermic Oxygenated Machine Perfusion for Unexpected Long Prolongation of Cold Preservation Time in...

Hypothermic oxygenated machine perfusion (HOPE) is occasionally used to overcome logistical issues and allow longer cold preservation time (CPT); however, reports regarding these situations in older brain-dead donors are lacking.

Retrospective analysis of kidney transplants (KTs) performed between January 1, 2015, to December 31, 2023, from extended criteria donors (ECDs) switched to HOPE after a median time of 17.1 h in static cold storage (SCS) for unexpected logistic reasons and with a median total CPT of 28.6 h (25.3-32.0) (n = 44, HOPE ECDs), compared with a control group of KTs (n = 44, L-ECDs) maintained in SCS alone with a low CPT (median, 10.4 h; range, 7.1-11.1) and matched for age, sex, donor age, donor eGFR, pre-emptive transplant, and cPRA.

No primary nonfunction was observed, and both death-censored graft survival (DCGS) and renal function progressively improved, remaining satisfactory and superimposable between groups up to two years post-transplant (97.7% of DCGS with mean eGFR 46.5 mL/min/1.73 m² [36-55.65] in HOPE-ECDs) versus 97.7% with 42.0 (30.2-48.2) in L-ECDs with similar KDPI (67% [49.75-86.5] vs. 72.5% [60.5-87.75], p = 0.475). These results were achieved in patients with HOPE-ECDs, who experienced higher rates of DGF (31.8% vs. 11.4%, p = 0.036). No differences were noted in infection or rejection rates.

Rescue by HOPE after SCS in ECDs with a very long CPT can achieve midterm outcomes similar to those with a low CPT in SCS alone, paving the way for its safe implementation in clinical practice.