ObjectiveTo evaluate the impact of prolonged ischaemia during partial nephrectomy (PN), which remains understudied despite its potential clinical relevance.Patients and MethodsOf 1371 patients managed with on‐clamp PN (2011–2014), 759 (55%) had imaging and assessment of serum creatinine levels before and after PN within the appropriate timeframes necessary for inclusion. This timeframe was chosen to allow for a robust analysis of both warm and cold ischaemia. Recovery from ischaemia (Recischaemia) was defined as ipsilateral glomerular filtration rate (GFR) preserved, normalized by percentage of parenchymal volume preserved (PPVP), and would be 100% if all nephrons recovered completely from ischaemia. Pearson correlation and multivariable linear regression models were used to assess associations between Recischaemia and ischaemia type and duration.ResultsOf 759 patients, 525 (69%) were managed with warm ischaemia. The median warm/cold ischaemia times were 22 and 30 min, respectively. Overall, the median percent ipsilateral GFR preserved, PPVP and Recischaemia were 79%, 83% and 96%, respectively. Segmented regression analysis demonstrated substantially greater decline in Recischaemia, beginning at approximately 30 min for warm ischaemia, which was not observed for hypothermia. Prolonged ischaemia (defined as >30 min) occurred in 197 patients (26%; 88 warm/109 cold). For limited ischaemia (≤30 min), hypothermia was often used for tumours with increased tumour size and complexity (P < 0.01), while for prolonged ischaemia, the warm/cold subgroups had similar patient and tumour characteristics. For limited ischaemia and prolonged hypothermia, median Recischaemia remained >95%, independent of ischaemia time. Differences in Recischaemia between the warm and cold cohorts became significant only after 30 min (P < 0.05). On multivariable analysis, prolonged warm ischaemia was associated with reduced Recischaemia (P = 0.02), which fell 3.9% for every additional 10 min beyond 30 min.ConclusionsOur data suggest that Recischaemia begins to decline significantly after 30 min during PN, although hypothermia was protective. Avoidance of prolonged warm ischaemia should be prioritized in patients with solitary kidneys and/or significant pre‐existing chronic kidney disease.

中文翻译：

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肾部分切除术期间长期缺血：温热与冷的影响


目的评估肾部分切除术 （PN） 期间长期缺血的影响，尽管具有潜在的临床相关性，但其研究仍然不足。患者和方法在 1371 名接受钳夹 PN 治疗的患者 （2011-2014） 中，759 名 （55%） 在 PN 前后在纳入所需的适当时间范围内进行了血清肌酐水平的影像学检查和评估。选择这个时间范围是为了对温缺血和冷缺血进行稳健分析。缺血恢复 （Recischaemia） 定义为保持同侧肾小球滤过率 （GFR），按保留实质体积百分比 （PPVP） 标准化，如果所有肾单位都从缺血中完全恢复，则为 100%。采用 Pearson 相关和多变量线性回归模型评估 Recischaemia 与缺血类型和持续时间之间的关联。结果在 759 例患者中，525 例 （69%） 接受温缺血治疗。中位热/冷缺血时间分别为 22 和 30 min。总体而言，保留同侧 GFR、PPVP 和雷西亚的中位百分比分别为 79% 、 83% 和 96%。分段回归分析显示，热缺血从大约 30 分钟开始，雷西缺血的下降幅度要大得多，而低温则没有观察到。197 例患者 （26%;88 例暖缺血/109 例寒冷缺血） 发生长时间缺血 （定义为 >30 min）。对于局限性缺血 （≤30 min），低温通常用于肿瘤大小和复杂性增加的肿瘤 （P < 0.01），而对于长期缺血，暖/冷亚组具有相似的患者和肿瘤特征。对于局限性缺血和长时间低体温，中位 Reciscemia 保持 >95%，与缺血时间无关。 暖队列和冷队列之间的 Recischaemia 差异仅在 30 min 后才变得显著 （P < 0.05）。在多变量分析中，长时间热缺血与回血减少相关 （P = 0.02），30 分钟后每增加 10 分钟，回血减少 3.9%。结论我们的数据表明，在 PN 期间 30 min 后，Recischaemia 开始显着下降，尽管低温具有保护作用。对于孤立肾和/或已有严重慢性肾病的患者，应优先避免长期热缺血。