Dialysis Access

Dialysis Access is another common reason patients visit the office. The vascular surgeon is involved in providing access for dialysis.

The simplest way to explain dialysis is to describe it as removing naturally occuring substances, excess water and dissolved products of metabolism, from the blood by a process of diffusion and filtration. The need for dialysis occurs when the kidneys no longer function properly; the need may be short or long term. The two main ways of receiving dialysis are hemodialysis and peritoneal dialysis. In both methods there is a semi-permeable  membrane which allows for the passage of water and dissolved substances from areas of high concentration (the blood of the patient) to areas of low concentration, the dialysate fluid. A semipermeable membrane allows the passage of some substances while inhibiting the passage of others.

In hemodialysis, the blood is circulated outside the body via a catheter (plastic tube), an AV graft or AV fistula, through a machine with a dialysis membrane, and back to the patient. In peritoneal dialysis, dialysis fluid is placed into the abdomen via a catheter. The dissolved substances flow across the peritoneum, a fine layer of tissue surrounding the abdominal organs, into the dialysis fluid. Several hours later the dialysate is removed from the abdomen.