Infectious complications of the hemodialysis access

Infectious complications of the vascular access are a major source of morbidity and mortality among hemodialysis (HD) patients. Numerous reports implicate the vascular access in up to 48 to 73% of all bacteremias in HD patients. The incidence of vascular access-related infection is highest when central venous dialysis catheters are employed. Native arteriovenous fistulas carry the lowest risk of infection. Unfortunately, prosthetic arteriovenous grafts, which represent the most common type of HD access in the United States, have been repeatedly shown to be a risk factor for bacteremic and nonbacteremic infections. Silent infection in old nonfunctional clotted prosthetic arteriovenous grafts has recently been recognized as a frequent cause of bacteremia and morbidity among HD patients. High proportions of infections related to the vascular access are caused by staphylococcal organisms, which carry high rates of mortality, recurrence, and metastatic complications. Management of vascular access-related infection has two aspects: The first relates to the choice, duration, and mode of administration of antibiotic therapy. Empiric antibiotic therapy, guided by demographic data and severity of illness, should be employed when the causative organisms are unknown. Prolonged administration of specific parenteral antibiotics is crucial in decreasing complications of infection, especially in cases of staphylococcal bacteremia. The second aspect relates to management of the vascular access. Efforts directed toward bacteriological cure should be concurrent with efforts to preserve native venous access sites whenever possible. Efforts to prevent vascular access-related infection should focus on increasing placement of arteriovenous fistulas and minimizing insertion of central venous dialysis catheters. Careful inspection and monitoring of the vascular access is of paramount importance in early detection of vascular access site-related infections. Several new approaches aimed at preventing catheter and prosthetic graft-related infection are being explored.