Brief initial and end-ischemic O2 supply via bubble and perfusate surface oxygenation during standard HMP demonstrated to be simple yet effective for improving early recovery of renal function in an ischemia-reperfusion porcine autotransplant model.

Darius, Tom [UCL] Vergauwen, Martial [UCL] Smith, Thomas Nath, Jay Patel, Kamlesh Aydin, Selda [UCL] Buemi, Antoine [UCL] De Meyer, Martine [UCL] Ludwig, Christian Gianello, Pierre [UCL] Mourad, Michel [UCL] et al.[show all]

Background Static cold storage (SCS) and hypothermic machine perfusion (HMP) are today the gold standard for kidney preservation. The aim of this study was to determine the ideal start time and least complicated method for adding oxygen during HMP to improve early graft function in a porcine kidney ischemia-reperfusion autotransplant model. Methods The left kidney of ±40 kg Landrace pig was exposed to 30 minutes of warm ischemia by vascular clamping and randomized after ex vivo cold flush. The LifePort Kidney Transporter® modified to include an external oxygenator was used in the following study groups: 1) 22h oxygenated HMP (HMPO (FiO 90%), n=8), 2) 2h HMPO2+20h HMP(n=6), and 3) 20h HMP + 2h HMPO (n=5). The LifePort kidney Transporter without external oxygenator but direct perfusate oxygenation via bubble and perfusate surface (FiO =95%) oxygenation was used in a 4th study group, 22h standard HMP including 30min at start and 1h end-ischemic O uploading (HMPO uploading). SCS and standard HMP (no active oxygen supply) for 22h served as control groups. Results The perfusate pO at the start and the end of HMP is shown in Figure 1 according to the study group. Graft recovery measured by serum creatine levels was superior in the 22h HMPO , the 2h HMPO +20h HMP and the HMPO2uploading groups compared with 22h SCS (p<0.0001), standard 22h HMP (p<0.0001) and 20h HMP+2hHMPO (p=0.0288) (Figure 2). Conclusion Our data suggest that during cold perfusion continuous oxygenation might not be required. Brief O uploading via bubble and perfusate surface oxygenation was shown to be as effective as continuous oxygenation via an external oxygenator to obtain supraphysiological pO and similar superior early graft function compared with standard HMP or SCS alone. Such simple but effective oxygenation method might easily get adopted in the clinic since it would hardly complicate handling or logistics during organ sharing.