Kidney transplantation is the optimal treatment for end-stage renal disease, but it is still severely limited by a lack of suitable organ donors. Kidneys from donation after circulatory death (DCD) donors have been used to increase transplant rates, but these organs are susceptible to cold ischemic injury in the storage period before transplantation, the clinical consequence of which is high rates of delayed graft function (DGF). Normothermic machine perfusion (NMP) is an emerging technique that circulates a warmed, oxygenated red-cell-based perfusate through the kidney to maintain near-physiological conditions. We conducted a randomized controlled trial to compare the outcome of DCD kidney transplants after conventional static cold storage (SCS) alone or SCS plus 1-h NMP. A total of 338 kidneys were randomly allocated to SCS (n = 168) or NMP (n = 170), and 277 kidneys were included in the final intention-to-treat analysis. The primary endpoint was DGF, defined as the requirement for dialysis in the first 7 d after transplant. The rate of DGF was 82 of 135 (60.7%) in NMP kidneys versus 83 of 142 (58.5%) in SCS kidneys (adjusted odds ratio (95% confidence interval) 1.13 (0.69–1.84); P = 0.624). NMP was not associated with any increase in transplant thrombosis, infectious complications or any other adverse events. A 1-h period of NMP at the end of SCS did not reduce the rate of DGF in DCD kidneys. NMP was demonstrated to be feasible, safe and suitable for clinical application. Trial registration number: ISRCTN15821205.

肾移植是终末期肾病的最佳治疗方法，但由于缺乏合适的器官捐献者，它仍然受到严重限制。循环死亡（DCD）供体捐献的肾脏已被用来提高移植率，但这些器官在移植前的保存期间容易受到冷缺血性损伤，其临床后果是移植物功能延迟（DGF）率较高。常温机器灌注 (NMP) 是一种新兴技术，可通过肾脏循环加温、含氧的红细胞灌注液，以维持接近生理的状态。我们进行了一项随机对照试验，比较单独传统静态冷藏 (SCS) 或 SCS 加 1 小时 NMP 后 DCD 肾移植的结果。总共 338 个肾脏被随机分配至 SCS（n  = 168）或 NMP（n  = 170），其中 277 个肾脏纳入最终意向治疗分析。主要终点是 DGF，定义为移植后前 7 天内透析的要求。NMP 肾脏中的 DGF 发生率为 135 例中的 82 例 (60.7%)，而 SCS 肾脏中的 DGF 发生率为 142 例中的 83 例 (58.5%)（调整后的优势比（95% 置信区间）1.13 (0.69–1.84)；P = 0.624 ）  。NMP 与移植血栓形成、感染并发症或任何其他不良事件的增加无关。SCS 结束时 1 小时的 NMP 不会降低 DCD 肾脏中 DGF 的比率。证明NMP可行、安全、适合临床应用。试用注册号：ISRCTN15821205。