الفهرس 
EpidemiologyOnly 14 pages are availabe for public view
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Abstract
About half of nosocomial bloodstream infections (BSIs) occur in intensive care units, and the majority are associated with the presence of an intravascular device. Catheter-related bloodstream infections (CR-BSI) are an important cause of morbidity and mortality worldwide, including resource-limited settings.
All types of intravascular catheters pose significant but varying risk of infection. Duration of catheterization, catheter material, insertion conditions, and site care also impact the risk of catheter-associated infections.
Bloodstream infection associated with central venous catheters can be attributed to four major sources: colonization from the skin, intraluminal or hub contamination, secondary seeding from a bloodstream infection, and contamination of the infusate In general, the diagnostic approach to catheter-related blood stream infection (CRBSI) consists of clinical evaluation and microbiologic confirmation with peripheral blood and catheter cultures. Catheter-related bloodstream infection (CRBSI) should be suspected when bloodstream infection occurs in the setting of a central venous catheter with no other apparent source.
Fever is the most sensitive clinical manifestation. Other clinical manifestations include hemodynamic instability, altered mental status, catheter dysfunction, and clinical signs of sepsis that start abruptly after catheter infusion.
Cultures of blood and catheters should be pursued in the setting of clinical suspicion for CRBSI when the local microbiology laboratory has appropriate resources for such testing. Blood cultures positive for S. aureus, coagulase-negative staphylococci or Candida species in the absence of other identifiable sources of infection should increase the suspicion for CRBSI.
In general, for circumstances in which systemic intravenous catheter-related infection diagnostic criteria are met, treatment requires determination regarding catheter management (eg, removal, salvage, or exchange) and antibiotic therapy (eg, selection of empiric therapy with subsequent tailoring to culture and sensitivity data).
The type of pathogen is important for guiding decisions regarding catheter management. Long term catheters (indwelling ≥14 days) should be removed in the setting of catheter-related bloodstream infection (CRBSI) due to S. aureus, P. aeruginosa, fungi or mycobacteria. Organisms of relatively low virulence that are difficult to eradicate (eg, Bacillus spp, Micrococcus spp, or Propionibacteria) should also prompt catheter removal if blood culture contamination has been ruled out.
The site chosen for catheter placement can influence the infection risk. For peripheral venous catheters, the risk is higher in the lower compared to the upper extremity and higher in the wrist or upper arm compared to the hand. For central venous or pulmonary catheters, infection is generally more common with catheters in the femoral and, probably to a lesser degree, internal jugular veins compared to the subclavian vein.