title: Are clinical signs accurate indicators of the cause of central venous catheter occlusion?
abstract: BACKGROUND
  Two hundred dysfunctional central venous catheters used for total parenteral nutrition and administration of cancer chemotherapy were radiographically examined in order to objectively identify thrombotic occlusions as the cause of catheter dysfunction.
  
  
  METHODS
  Outcomes of radiographic dye injections were compared with factors such as the inability to aspirate blood or to infuse fluids, catheter type, and duration of catheter placement.
  
  
  RESULTS
  Catheter type and duration of placement were not significant factors for predicting the type of dysfunction. Failure to withdraw blood was associated with 96% of the thrombosed catheters; this was also associated with 65% of the catheters with nonthrombotic dysfunctions. Once the cause of catheter occlusion was correctly identified, 90% of the catheters were restored to normal function.
  
  
  CONCLUSIONS
  Inability to withdraw blood from a catheter does not necessarily mean it is occluded by thrombus. Mechanical complications account for a significant portion of dysfunctional catheters.
authors.affiliation: Department of Internal Medicine, University of Nebraska Medical Center, Omaha 68198-1210, USA.
authors.forename: L C
authors.initials: LC
authors.lastname: Stephens
authors.forename: W D
authors.initials: WD
authors.lastname: Haire
authors.forename: G D
authors.initials: GD
authors.lastname: Kotulak
mesh_terms: D002405:Catheterization, Central Venous; D004868:Equipment Failure; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy*; D010289:Parenteral Nutrition, Total; D011446:Prospective Studies; D011859:Radiography; D013927:Thrombosis