Central venous catheters: infection risks

Central venous catheters (CVCs) are generally inserted into a high-flow major vein in the subclavian, neck or inguinal region.

CVCs that are intended for short-term use are generally inserted directly into a vein and often have multiple lumens to allow multi-therapy access in complex surgical cases and for patients requiring intensive care support. Infection associated with a central venous catheter usually results in bacteraemia, with serious consequences. Strict management protocols can minimise infection risk – see the National Health and Medical Research Council’s Australian Guidelines for the Prevention and Control of Infection in Healthcare. Nevertheless, CVCs for short-term use can be readily removed if they become infected, as long as central access is no longer required or there are other access options.

CVCs intended for long-term use include those used for chemotherapy or parenteral nutrition (eg Hickman catheter, Portacath, ports) and may have one or more lumens. A long-term central venous catheter is surgically inserted via a subcutaneous tunnel before entering the subclavian vein, and may be sutured in place to avoid becoming dislodged. The subcutaneous tunnel enables more convenient location of the access hub on the chest, while also providing a potential barrier against infection. Patients with infection associated with a long-term central venous catheter have a high likelihood of bacteraemia. Removal of long-term CVCs is usually more complicated than for short-term ones and generally requires a specialist. In addition, these patients often have major comorbidities that require ongoing intravenous access, and insertion of a new central venous catheter while actively infected risks contamination of the new catheter.

Haemodialysis catheters (eg Vascath, Permacath) require surgical insertion into a major vein with sufficient blood flow for dialysis. This may require insertion into the femoral vein, which is associated with a higher risk of infection (especially with gram-negative pathogens) than use of the subclavian or neck veins. Infection of haemodialysis catheters almost always results in bacteraemia. Removal of the haemodialysis catheter is complicated, both technically and because intravenous access must be maintained for dialysis (but patients may have limited alternative veins to achieve this).