Hypothermic machine perfusion improves Doppler ultrasonography resistive indices and long-term allograft function after renal transplantation: a single-centre analysis

Abstract

Objectives: To evaluate whether hypothermic machine perfusion (HMP) of transplanted kidneys can improve long-term renal allograft function compared with static cold storage (CS).

Methods: We evaluated whether graft Doppler ultrasonography resistive indices improved with the use of HMP compared with CS preservation, and examined whether these improvements were predictive of long-term graft function. A total of 30 kidney transplants (15 pairs) were examined. One of the kidney pairs was placed on CS and transplanted first (CS group, n = 15). The other kidney of each pair was placed on HMP and transplanted after the CS group (HMP group, n = 15). Doppler ultrasonography was performed on days 1 and 7 after transplantation and resistive indices were evaluated. The estimated glomerular filtration rate (eGFR) was monitored for 24 months after transplantation.

Results: Despite longer cold ischaemia times, kidneys maintained with HMP had lower resistive indices (P = 0.005) with correspondingly higher eGFR throughout the follow-up. Subgroup analysis showed that the HMP-induced improvement in postoperative eGFR was greatest in kidneys obtained from donation after cardiac death (DCD), even at 2 years after transplantation (P = 0.008).

Conclusions: HMP of transplant kidneys appears to improve vascular resistance after transplantation and has a positive impact on long-term allograft function compared with CS in the population of recipients of DCD kidneys.

Keywords: Doppler ultrasonography; graft function; hypothermic mechanical perfusion; organ preservation; renal transplantation.