Dialysis Catheter

Excerpt

Dialysis catheters are artificial indwelling transcutaneous conduits that are used to access the intravascular space or the intraperitoneal space for renal replacement therapy (RRT). There are two broad types of dialysis catheter: those used for extracorporeal modes of RRT (such as hemodialysis, hemofiltration, hemodiafiltration or ultrafiltration), and those used for peritoneal dialysis.

1. Catheters for extracorporeal RRT are essentially wide-bore central venous lines that allow blood to be withdrawn from and returned to the patient efficiently. In this way, the patient's blood can be temporarily removed from the body for processing in an extracorporeal RRT machine which may perform any of hemodialysis, hemofiltration, hemodiafiltration or ultrafiltration as desired. Depending on the intended duration of therapy, the catheter can be inserted directly through the skin into the target vein, or it may first pass under the skin through a short subcutaneous tunnel before it reaches the vein, with an integral felt cuff securing it to the local tissue.

2. Catheters for peritoneal dialysis allow fluid known as dialysate to be instilled into the intraperitoneal space, where it remains in contact with the peritoneal membrane for some time before being removed. In this form of therapy, dialysis occurs directly across the peritoneal membrane itself.