Haemodialysis catheters.

Haemodialysis central venous catheters are commonly being introduced in patients requiring emergency or chronic renal replacement therapy. There are two main categories of haemodialysis catheters: 1. Non-tunnelled, uncuffed, designed for short-term venous access of up to three weeks. They are, made of stiff materials such as polyurethane or polyvinyl. 2. Tunnelled, cuffed catheters. They are usually made of silicone, silastic elastomeric, or carbothane, are much softer and can be used for both temporary and permanent access. The latter catheters are usually inserted via peel-away sheaths, introduced using the Seldinger technique. Unlike surgically implanted devices, they can be used immediately after correct placement under fluoroscopy. The paper reviews catheters currently available, including discussion of materials, design, vascular access sites, and possible complications.