Is antithrombotic prophylaxis required in cancer patients with central venous catheters? Still an open question

Prevention of central venous catheter-associated thrombosis: a meta-analysis

PURPOSE

Anticoagulant prophylaxis in patients with central venous catheters is controversial. We performed a meta-analysis of randomized controlled trials of anticoagulant prophylaxis in patients with central venous catheters.

METHODS

MEDLINE and EMBASE were searched up to May 2006, supplemented by manual searches of conference proceedings and bibliographies.

RESULTS

Fifteen trials were included. Unfractionated heparin infusion, oral fixed low-dose vitamin K antagonist, and subcutaneous low-molecular-weight heparin were evaluated. For all catheter-associated deep vein thrombosis (symptomatic and asymptomatic combined), the summary relative risks ranged from 0.31 to 0.73 (all achieved statistical significance). For symptomatic deep vein thrombosis, the summary relative risks ranged from 0.28 to 0.72, but did not achieve statistical significance for any individual regimen.

CONCLUSION

Anticoagulant prophylaxis is effective for preventing all catheter-associated deep vein thrombosis in patients with central venous catheters. The effectiveness for preventing symptomatic venous thromboembolism, including pulmonary embolism, remains uncertain.

Thromboprophylaxis of central venous lines in children with cancer: the first steps taken on the long road ahead

Approximately one third of children with malignancy and central venous lines develop catheter-related thrombosis, with the reported sequelae including death, pulmonary embolism, chylothoraces, superior vena cava syndrome and post-thrombotic syndrome. These complications prompt the design and completion of randomized, controlled trials to determine a safe and efficacious therapy to prevent these thromboses. The authors Ruud et al. have presented a well-designed, randomized, controlled trial which demonstrates the lack of utility of using low-dose warfarin to prevent catheter-related thrombosis in children with central lines and acute lymphoblastic leukaemia. The difficulties with warfarin in children are again demonstrated in this study.

CONCLUSION

Further studies are warranted using other thromboprophylactic agents with less or no monitoring and fewer drug interactions, including the newer anticoagulant agents such as direct thrombin inhibitors.