Nephrology and Infectious disease R&D.
Since 2013, the Portuguese law allows the harvest of organs from uncontrolled circulatory death donors (DCD) (Maastricht II). Cold ischemia time (CIT) is a modifiable variable with impact on the outcomes of kidney grafts from controlled DCD (Maastricht III). Literature on the effect of CIT in uncontrolled DCD transplantation with Abdominal Normothermic Oxygenated Recirculation support (uDCD-ANOR) is missing.
A retrospective study of uDCD-ANOR kidney allografts implanted in our center between January, 1st 2016 and November, 14th 2017, was performed. Beside descriptive statistics, we analyzed the impact of CIT on transplant-related outcomes.
32 kidney allografts were implanted in our center. Donors (M:F; 14:5) had a mean age of 47.5 ± 14.1 years. Mean warm ischemia time was 93 ± 23.2 minutes and the mean time on Abdominal Normothermic Oxygenated Recirculation support was 174.8 ± 30.7 minutes.
Receptors (M:F 20/12) had a mean age of 53.1 ± 9.2 years and their mean time of dialysis was 43.3 ± 17.3 months. All had a low immunological risk. 93.8% received anti-thymocyte globulin (ATG-Fresenius) as induction immunosuppressive therapy. The mean cumulative dose was 12.6 ± 4.5 mg/kg. All patients received our standard maintenance protocol: tacrolimus, prednisolone, and mycophenolate mofetil.
68.8% of the population had delayed graft function (DGF) and 9.4%, primary nonfunction. We had 6 cases of acute rejection (three humoral and three cellular rejection cases), with all but one successfully treated. The 3-month mean estimated glomerular filtration rate (eGFR) after transplantation was 57.3 ± 22.4 ml/min/1,73 m2. Our mean patient follow-up time is 7.5 ± 5.3 months.
Mean CIT was 13.7 ± 2.8 hours (1st kidney 12.2 ± 1.5 hours; 2nd 16 ± 2.1 hours). Regarding grafts from donors where both kidneys were implanted, the 3-month eGFR from the 1st kidney is significantly higher than the 2nd kidney (p=0,001), but we did not find differences in the rate of DGF (p=0,661). In this sub-group of donors, the rate of DGF did not associate with 3-month eGFR (p=0,875). Regarding the whole population, 3-month eGFR is significantly higher when CIT is inferior to 14 hours (73,2 vs 46,3 ml/min/1,73m2) (p=0,003).
uDCD-ANOR kidney transplantation is not only a viable option but already represents a critical solution for the increase of the donor pool in our region. Although our patient follow-up time is short, our early results are promising, with a lower DGF rate and a higher 3-month eGFR than previously reported from other centers that perform uDCD-ANOR kidney transplantation. To further improve the uDCD-ANOR program, CIT and its quality should be addressed.