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Central Venous Angioaccess for Hemodialysis and Its Complications

In 1959, Wayne Quinton and Belding Scribner designed the external arteriovenous (AV or Scribner) shunt (1). It became the preferred method of vascular access and for many years the method of choice in acute situations requiring hemodialysis. However, Scribner shunts are prone to a relatively high incidence of clotting and infection and a limited survival time. Moreover, the creation of a temporary external shunt often results in the loss of a peripheral vessel as a potential access site. It also requires the expertise of a vascular surgeon to place. Repeated femoral vein catheterizations with single lumen plastic catheters replaced Scribner shunts as the preferred acute access because they were simple to perform and avoided unnecessary surgery (2). Rare complications such as iliofemoral thrombosis, retroperitoneal hematoma, and pulmonary embolization have been reported with femoral vein catheterizations. These complications can be prevented by leaving the catheters in the femoral vein for less than 48 hours and by avoiding the insertion of the guidewire or the catheter against resistance. However, both the need for a physician to insert the catheter prior to each dialysis and the risk of vascular compromise resulted in a continued search for other methods to access a central vein for hemodialysis. Yet femoral catheterization remains the safest and quickest access to the circulation, and it continues to be heavily employed, particularly in unstable bedbound patients. Central venous catheterization (utilizing either the subclavian or internal jugular vein) has become a well-accepted method of both temporary and longterm vascular access for hemodialysis (Table I). The complications of a central venous access are related mainly to the properties of the catheter, insertion procedure, and the occurrence of thrombosis and infection after insertion (Table 2). This review will