Pressure-controlled continuous normothermic ex vivo kidney perfusion (NEVKP) improves renal graft function in pigs, say researchers. Markus Selzner and colleagues suggest that use of this preservation technique might reduce rates of delayed graft function and improve outcomes in kidney transplantation. “We aim to maintain physiologic conditions during NEVKP,” says Selzner. “The kidneys are kept at 37°C and supplied with nutrition and oxygen using a perfusion solution with erythrocytes and a normal oncotic pressure. The conditions are chosen so that the kidney functions ex vivo as it would in the body.”

NEVKP could result in better quality grafts and might offer the opportunity to assess grafts prior to transplantation

Using pig autotransplantation models of heart-beating donation (HBD) and donation after circulatory death (DCD), the researchers showed that 8 h of NEVKP maintained graft function without preservation injury. In the HBD model, serum creatinine and blood urea nitrogen (BUN) levels at day 10 post-transplantation were similar to baseline in NEVKP graft recipients, whereas recipients of grafts that had undergone static cold storage (SCD) had increased serum creatinine and BUN levels. In the DCD model, NEVPK graft recipients had significantly better post-transplantation kidney function than SCD graft recipients, as indicated by serum creatinine, BUN and potassium levels. In both models, animal survival was similar in SCD and NEVPK groups and histological analysis showed no differences in graft tubular injury, interstitial inflammation, oedema or fibrosis.

“NEVKP could result in better quality grafts and might offer the opportunity to assess grafts prior to transplantation,” concludes Selzner.