Pediatric hemodialysis: lessons from the past, ideas for the future.

Pediatric hemodialysis (HD) continues to be the secondary form of dialysis in children of all age groups. This constitutes 9%, 26%, 33% and 46% of all children on dialysis at age ranges of 0 to 1 year, 2 to 5 years, 6 to 12 years and > 12 years, respectively. The reasons for HD being less common are multifactorial including: (1) distance of the patient from the dialysis center, (2) access difficulties, (3) bias that growth is less on HD as compared to peritoneal dialysis, (4) difficulties in identifying infant and pediatric specific dialyzers, as well as other equipment. HD access remains in the forefront of problems associated with HD in pediatrics. Access is attained by external percutaneous catheters (63%) with 82% being placed via the subclavian approach. Internal access is attained by an arterial venous (A-V) fistula (20.1%) and internal A-V shunts (17%) with the majority of internal access being in the lower arm. Access revisions occurred at a rate of 70%, 55% and 23% when the access was an external catheter, internal A-V graft and internal A-V fistula, respectively. The cause of revision in the internal access was clotting in over 50% of the time. Infection, clotting and "access malfunction" occurred in the external percutaneous access at 18%, 29%, and 16%, respectively. Twenty-eight percent of external access revisions were due to placement of a more permanent access. No report to date on growth, incidence of vascular stenosis or vascular thrombosis from external access, optimal Kt/V based by age, weight or surface area, or home HD is available. The challenge of bringing HD, as a primary modality of dialysis in children, remains with many questions that need to be addressed and many obstacles to be overcome.