Deep vein thrombosis associated with central venous catheters - a review.

Central venous catheters (CVCs) are frequently used in patients for a variety of indications such as cancer treatment, diagnostic monitoring, parenteral nutrition, hemodialysis, cardiac pacing, and administration of fluids, blood products or medication [1]. The benefit derived from a CVC may be offset by thrombosis and associated complications, such as pulmonary embolism (PE), CVC dysfunction, infection or loss of central venous access. In the long term patients with thrombosis may suffer from a post-thrombotic syndrome [1,2]. The CVC-related thrombosis is an issue of importance to many clinicians, and insight into the different aspects is crucial to guide decisions in treatment in often vulnerable patients in daily practice. In medical literature, there is a lack of uniformity and uncertainty about several entities of CVCrelated thrombosis. First, two types of CVC-related thrombosis must be clearly distinguished; i.e. clinically manifest and subclinical thrombosis. Furthermore, the type of thrombosis and the incidence is defined by the diagnostic strategy in patients with a CVC. Anticipation of the risk of CVC-related thrombosis and the identification of certain high-risk patients who are prone to develop thrombosis and secondary complications, is essential to initiate early preventive measurements such as prophylactic anticoagulation. The need for anticoagulant prophylaxis is however still a subject of discussion [3,4]. Finally, for the treatment of established CVC-related thrombosis, several therapeutic options were evaluated in literature. General recommendations of anticoagulant treatment, and whether CVC removal is necessary or not, is warranted. The primary aim of this review is to describe the diagnostic methods and their performance, the incidence and risk factors, complications, prevention and treatment of CVC-related thrombosis from a practical clinical point of view. English medical literature studies were retrieved by an extensive Medline search (Pubmed ) and bibliographies of the obtained studies were crosschecked where necessary. For each subject, only those studies with the strongest level of evidence, as defined and discussed in the subsequent paragraphs, were selected and reviewed.