Department of Intensive Care, Royal Free Hospital, London NW3 2QG, UK.
J Hepatol. 2009 Sep;51(3):504-9. doi: 10.1016/j.jhep.2009.05.028. Epub 2009 Jun 24.
BACKGROUND/AIMS: Clotting of haemofiltration circuits is a major complication of continuous renal replacement therapies (CRRT), yet systemic anticoagulation risks haemorrhage. Traditionally, patients with liver failure are managed with no or minimal anticoagulation, because of abnormal clotting tests and the perceived, increased bleeding risk.
We retrospectively reviewed CRRT circuit life in 50 patients; 3 groups of liver failure patients treated with CRRT (acute liver failure (ALF), acute on chronic liver disease (ACLD) and post-elective liver transplantation (LTx)), with two control groups; systemic sepsis (SS) and haematological malignancy (Haem).
CCRT circuit life was significantly greater in the Haem group, compared to the others; 24.3+/-23.9h, vs. 11+/-10.5 ALF, 11.6+/-6.6 ACLF, 7.4+/-5.1 LTx and 9.2+/-6.5 SS, p<0.05, with Haem group requiring fewest new CCRT circuits within 48h; 2.4+/-1.0 vs. 4.3+/-1.3 ALF, 4.2+/-2.1 ACLF, 5.3+/-1.5 LTx and 4.6+/-1.5 SS, p<0.05 and least blood transfusions; 1.2+/-1.3 vs. 4.8+/-4.2 ALF, 4.2+/-4.1 ACLF, 2.2+/-2.1 LTx and 3.0+/-1.5 SS. Transmembrane pressures were higher in those CCRT circuits with haemofilter/dialyzer clotting, compared to other causes, such as access dysfunction (123+/-74 vs. 71.8+/-29.3 mm Hg, p=0.009). In those patients in whom anticoagulation was started due to repeated filter clotting, circuit life improved from 5.6+/-3.4 to 19+/-12.7h, p<0.01.
Despite abnormal laboratory coagulation tests and thrombocytopenia, CCRT circuits clot frequently in liver failure patients. Anticoagulation did improve CRRT circuit survival without an obvious increase in bleeding or blood transfusion requirement. Thus anticoagulation should be considered in these patients with repeated circuit clotting.
背景/目的：血液滤过回路的凝血是连续肾脏替代疗法（CRRT）的主要并发症，但全身抗凝会增加出血风险。传统上，由于凝血试验异常和认为出血风险增加，肝功能衰竭患者接受无抗凝或最小抗凝治疗。
我们回顾性分析了 50 例接受 CRRT 治疗的肝功能衰竭患者（急性肝衰竭（ALF）、慢性肝疾病急性加重（ACLD）和择期肝移植后（LTx））的 CRRT 回路寿命，并设立了两个对照组：全身脓毒症（SS）和血液系统恶性肿瘤（Haem）。
Haem 组的 CRRT 回路寿命明显长于其他组；24.3+/-23.9h，而 ALF 组为 11+/-10.5h，ACLD 组为 11.6+/-6.6h，LTx 组为 7.4+/-5.1h，SS 组为 9.2+/-6.5h，p<0.05，Haem 组在 48 小时内需要更换的新 CRRT 回路最少；2.4+/-1.0 次，而 ALF 组为 4.3+/-1.3 次，ACLD 组为 4.2+/-2.1 次，LTx 组为 5.3+/-1.5 次，SS 组为 4.6+/-1.5 次，p<0.05，需要的输血也最少；1.2+/-1.3 次，而 ALF 组为 4.8+/-4.2 次，ACLD 组为 4.2+/-4.1 次，LTx 组为 2.2+/-2.1 次，SS 组为 3.0+/-1.5 次。与其他原因（如通路功能障碍）相比，由于血液滤器/透析器凝血导致的 CRRT 回路中的跨膜压力更高，123+/-74mmHg 比 71.8+/-29.3mmHg，p=0.009。对于那些由于反复滤器凝血而开始抗凝的患者，CRRT 回路的存活时间从 5.6+/-3.4 小时提高到 19+/-12.7 小时，p<0.01。
尽管存在实验室凝血试验异常和血小板减少，但肝功能衰竭患者的 CRRT 回路经常发生凝血。抗凝确实改善了 CRRT 回路的存活，而没有明显增加出血或输血的需求。因此，对于反复出现回路凝血的患者，应考虑抗凝治疗。
