Akl E A, Karmath G, Yosuico V, Kim S Y, Barba M, Sperati F, Cook D, Schünemann H J
State University of New York at Buffalo, Medicine, ECMC, CC-142, 462 Girder Street, Buffalo, New York 14215, USA.
Cochrane Database Syst Rev. 2007 Jul 18(3):CD006468. doi: 10.1002/14651858.CD006468.pub2.
Central venous catheter (CVC) placement increases the risk of thrombosis in cancer patients. Thrombosis often necessitates the removal of the CVC, resulting in treatment delays and thrombosis related morbidity and mortality.
To evaluate the efficacy and safety of anticoagulation in reducing venous thromboembolic (VTE) events in cancer patients with CVC.
A comprehensive search for studies of anticoagulation in cancer patients up to January 2006 was conducted in the following databases: The Cochrane Central Register of Controlled Trials ( CENTRAL), MEDLINE, EMBASE and ISI the Web of Science.
Randomized controlled trials (RCTs) comparing unfractionated heparin (UFH), low molecular weight heparin (LMWH), vitamin K antagonists (VKA), fondaparinux or ximelagatran to no intervention or placebo in cancer patients with a CVC or comparing two different anticoagulants.
Data was extracted on methodological quality, patients, interventions and outcomes including all cause mortality (primary outcome), premature CVC removal, catheter-related infections, CVC site and non CVC site deep venous thrombosis (DVT), pulmonary embolism (PE), major and minor bleeding and thrombocytopenia.
Of 3986 identified citations nine RCTs were included in the meta-analysis including one published as an abstract and one focusing on paediatric patients not included in the meta-analysis. None of these RCTs tested fondaparinux or ximelagatran. The use of heparin in cancer patients with CVC was associated with a trend towards a reduction in symptomatic DVT (Relative Risk (RR) = 0.43; 95% Confidence Interval (CI): 0.18 to 1.06), but the data did not show any statistically significant effect on mortality (RR = 0.74; 95% CI: 0.40 to 1.36), infection (RR = 0.91; 95% CI: 0.36 to 2.28), major bleeding (RR = 0.68; 95% CI: 0.10 to 4.78) or thrombocytopenia (RR = 0.85; 95% CI: 0.49 to 1.46). The effect warfarin on symptomatic DVT was not statistically significant (RR = 0.62; 95% CI: 0.30 to 1.27). When studies assessing different types of anticoagulants were pooled, symptomatic DVT rates were significantly reduced (RR = 0.56; 95% CI: 0.34 to 0.92).
AUTHORS' CONCLUSIONS: Cancer patients with CVC considering anticoagulation, should consider the possible benefit of reduced incidence of thromboembolic complications with the burden and harms of anticoagulation. Future studies should be adequately powered and evaluate the effects of newer anticoagulants such as fondaparinux and ximelagatran in cancer patients with CVC.
中心静脉导管（CVC）置入会增加癌症患者发生血栓形成的风险。血栓形成常常需要拔除CVC，从而导致治疗延误以及与血栓形成相关的发病率和死亡率。
评估抗凝治疗在降低置有CVC的癌症患者静脉血栓栓塞（VTE）事件方面的疗效和安全性。
截至2006年1月，在以下数据库中全面检索了有关癌症患者抗凝治疗的研究：Cochrane对照试验中心注册库（CENTRAL）、医学期刊数据库（MEDLINE）、荷兰医学文摘数据库（EMBASE）以及科学引文索引（ISI）科学网。
随机对照试验（RCT），比较普通肝素（UFH）、低分子量肝素（LMWH）、维生素K拮抗剂（VKA）、磺达肝癸钠或希美加群与未进行干预或安慰剂对置有CVC的癌症患者的影响，或比较两种不同的抗凝剂。
提取了有关方法学质量、患者、干预措施和结局的数据，包括全因死亡率（主要结局）、过早拔除CVC、导管相关感染、CVC部位和非CVC部位的深静脉血栓形成（DVT）、肺栓塞（PE）、大出血和小出血以及血小板减少症。
在3986条检索到的文献中，9项RCT被纳入荟萃分析，其中1项以摘要形式发表，1项聚焦于儿科患者未纳入荟萃分析。这些RCT均未对磺达肝癸钠或希美加群进行试验。在置有CVC的癌症患者中使用肝素与有症状DVT发生率降低的趋势相关（相对危险度（RR）=0.43；95%置信区间（CI）：0.18至1.06），但数据未显示对死亡率（RR =0.74；95% CI：0.40至1.36）、感染（RR =0.91；95% CI：0.36至2.28）、大出血（RR =0.68；95% CI：0.10至4.78）或血小板减少症（RR =0.85；95% CI：0.49至1.46）有任何统计学上的显著影响。华法林对有症状DVT的影响无统计学意义（RR =0.62；95% CI：0.30至1.27）。当汇总评估不同类型抗凝剂的研究时，有症状DVT发生率显著降低（RR =0.56；95% CI：0.34至0.92）。
考虑进行抗凝治疗的置有CVC的癌症患者，应权衡抗凝治疗可能带来的降低血栓栓塞并发症发生率的益处与负担和危害。未来的研究应有足够的样本量，并评估新型抗凝剂如磺达肝癸钠和希美加群对置有CVC的癌症患者的影响。
