Machine Perfusion Decreases Delayed Graft Function in Donor Grafts With High Kidney Donor Profile Index

PO2 21% oxygenated hypothermic machine perfusion in kidney transplantation: Any clinical benefit?

BACKGROUND

In deceased donor kidney transplantation (KT), the use of hypothermic machine perfusion (HMP) has been acquiring the status of best practice in the pre-transplant management of kidney grafts. Two types of HMP are currently available, oxygenated HMP and non-oxygenated HMP. However, data on the real clinical impact of oxygenation on KT outcome are still heterogeneous.

METHODS

Retrospective study on a cohort of 103 patients transplanted with a single kidney graft that was managed either with end-ischemic oxygenated (O₂ group, Waves Machine, n = 51, 49.5%) or non-oxygenated HMP (no-O₂ group, Life Port Kidney Transporter Machine, n = 52, 50.5%), during the period January 2016-December 2020. Oxygenation was performed at pO₂ 21%.

RESULTS

The median cold ischemia time was 29 h:40 min [IQR 26 h:55 min-31 h:10 min] and the prevalence of grafts from extended criteria donors (ECD) was 46.7%, with a median kidney donor profile index (KDPI) of 72 [41-94]. The study groups were homogeneous in terms of recipient characteristics, ischemia times and donor characteristics. O₂ and no-O₂ groups showed comparable outcomes in terms of delayed graft function (O₂ vs no-O₂, 21.5% vs 25%, p = 0.58), vascular (0.2% vs 0.2%, p > 0.99) and urologic (13.7% vs 11.5%, p = 0.77) complications, and episodes of graft rejection (11.7% vs 7.7%, p = 0.52). At 1 year follow up, even creatinine serum levels were comparable between the groups (1.27 mg/dL [1.09 and 1.67] vs 1.4 mg/dL [1.9-1.78], p = 0.319), with similar post-transplant trend (p = 0.870). No significant benefit was either observed in ECD or KDPI > 60 subgroups, respectively.

CONCLUSIONS

Oxygenation at pO₂ 21% during HMP seems not to significantly enhance the KT outcomes in terms of postoperative complications or graft function.

Efficacy and Safety of Machine Perfusion for Brain Death Marginal Donor Kidney Transplantation: A Report of 2 Cases

BACKGROUND

After the revised organ transplant law came into effect in Japan, donations of organs under brain death have been increasing; however, because of the expansion of donor indications, donations from expanded criteria donors and cardiac arrest donors (donation after cardiac death) have also increased. In kidney transplantation, ischemia-reperfusion injury results in a high rate of delayed graft function, which adversely affects patients' long-term prognoses. Hypothermic machine perfusion preservation results in superior postoperative function and survival rates compared with cold storage preservation. We used an organ preservation device for kidneys and performed a graft viability evaluation before to kidney transplantation.

METHODS

We used the CMP-X08 perfusion device (Chuo-Seiko Co, Ltd, Asahikawa, Hokkaido, Japan) and Belzer MPS solution to preserve the donated organ. The perfusion pressure and temperature were monitored during cold storage with continuous perfusion. Standard renal transplantation protocols were followed. A renal biopsy was performed 1 hour after transplantation and the renal function was evaluated. This study followed the principles of the Declaration of Helsinki.

RESULTS

The first presented case is of a 63-year-old woman who received a kidney from a middle-aged man with brain death due to hypoxic encephalopathy. The creatinine at the time of admission was 0.9 mg/dL and at the time of excision was 2.86 mg/dL. The total perfusion time was 120 minutes. The total ischemia time was 7 hours and 15 minutes. The recipient urinated 115 minutes postoperatively, and no dialysis was required. The second presented case is of a 47-year-old man with a 15-year history of dialysis who received a kidney from a middle-aged woman with brain death due to subarachnoid hemorrhage. The creatinine at the time of admission was 0.8 mg/dL and at the time of excision was 0.77 mg/dL. The total perfusion time was 240 minutes. The total ischemia time was 13 hours and 14 minutes. The recipient urinated 38 minutes postoperatively, and no dialysis was required.

CONCLUSIONS

Mechanical perfusion storage performed for 2 to 4 hours resulted in a viable organ that was successfully transplanted in both cases.

Predictors and one-year outcomes of patients with delayed graft function after deceased donor kidney transplantation

BACKGROUND

Delayed graft function (DGF) is closely associated with the use of marginal donated kidneys due to deficits during transplantation and in recipients. We aimed to predict the incidence of DGF and evaluate its effect on graft survival.

METHODS

This retrospective study on kidney transplantation was conducted from January 1, 2018, to December 31, 2019, at the Second Xiangya Hospital of Central South University. We classified recipients whose operations were performed in different years into training and validation cohorts and used data from the training cohort to analyze predictors of DGF. A nomogram was then constructed to predict the likelihood of DGF based on these predictors.

RESULTS

The incidence rate of DGF was 16.92%. Binary logistic regression analysis showed correlations between the incidence of DGF and cold ischemic time (CIT), warm ischemic time (WIT), terminal serum creatine (Scr) concentration, duration of pretransplant dialysis, primary cause of donor death, and usage of LifePort. The internal accuracy of the nomogram was 83.12%. One-year graft survival rates were 93.59 and 99.74%, respectively, for the groups with and without DGF (P < 0.05).

CONCLUSION

The nomogram established in this study showed good accuracy in predicting DGF after deceased donor kidney transplantation; additionally, DGF decreased one-year graft survival.