Abstract: Renal replacement therapy（RRT） is effective in supporting impaired kidney function，maintaining homeostasis，as well as removing inflammatory mediators，harmful?metabolites and toxin in critically ill children. The accepted timing of initiating RRT?in acute kidney injury（AKI） patients are severe metabolic acidosis（pH＜7.1），hyperkalaemia（K+＞6.5 mmol/L），uraemic associated encephalopathy and bleeding diathesis，and fluid overload when medical management fails. Continuous renal replacement therapy（CRRT） has become the preferred technique to manage fluid administration in septic AKI or hemodynamically unstable patients，but its adequate timing remains unclear. The dose of CRRT can be divided into renal replacement therapy dose［ultrafiltration dose 20-35 mL/（kg·h）］ and sepsis treatment dose［ultrafiltration dose≥35 mL/（kg·h）］. The use of high volume hemofiltration（HVHF）［replacement dose≥50 mL/（kg·h）］ has demonstrated clinical benefits in septic shock patients by reversing the abnormal hemodynamics.

Key words: renal replacement therapy, timing, dose, critically ill, child

摘要： 儿童危重病中的肾替代治疗（renal replacement therapy， RRT）主要作用是替代受损肾功能， 稳定内环境，清除有害代谢产物、 炎症介质和毒素等。RRT绝对适应证为： 急性肾损伤（AKI）患儿出现严重高钾血症（K+＞6.5 mmol/L），严重酸中毒（pH值＜7.1），尿毒症相关性脑病和凝血病，以及利尿剂治疗无效的液体超载。连续血液净化（continuous renal replacement therapy，CRRT）适应于脓毒症合并AKI或血流动力学不稳定患儿的液体管理， 合适的时机仍有待循证。CRRT治疗剂量分为肾替代治疗剂量［超滤量20～35 mL/（kg·h）］和脓毒症治疗剂量［超滤量≥35 mL/（kg·h）］。高容量血液滤过［置换液剂量≥50 mL/（kg·h）］可能有助于稳定脓毒性休克患儿的血流动力学指标。

关键词: 肾替代治疗, 时机, 剂量, 危重症, 儿童