Clinical challenges, surgical decision-making, and experience from Cologne
Pediatric vascular access surgery remains one of the most demanding areas of dialysis access care. Small vessels, complex anatomy, prolonged maturation, and the prospect of kidney transplantation make every surgical decision particularly important.
At the 15th Cologne Home Dialysis Congress in April 2026, I presented our experience with pediatric vascular access surgery, focusing on a practical question:
How small is too small for successful AVF creation?
Guidelines and clinical reality
International guidelines generally favor arteriovenous fistulas (AVFs) over long-term central venous catheters for children requiring maintenance hemodialysis, provided that the anatomy and clinical circumstances are suitable.
Yet clinical reality is often different.
Many children begin hemodialysis through central venous catheters. Some require urgent dialysis, others are awaiting transplantation, and in very small children the available vessels may appear unsuitable for surgical access creation.
The decision is therefore rarely as simple as following a guideline recommendation.
The challenge of small vessels
Small vessel diameter is certainly an important technical limitation, but it should never be considered in isolation.
In our practice in Cologne, we have considered AVF creation in selected children weighing more than approximately 18 kg, including cases with arterial diameters as small as 1 mm.
These are not universal thresholds. They reflect our clinical approach, in which vessel quality, anatomy, expected maturation, and the child's individual treatment plan must all be considered.
Careful preoperative duplex ultrasound, ideally performed jointly by the surgeon and pediatric nephrologist, is essential.
During surgery, magnification and precise microsurgical technique become particularly important. We also routinely assess intraoperative blood flow, aiming for a flow exceeding 100 mL/min.
However, a technically successful anastomosis does not automatically guarantee a usable dialysis access.
Choosing the right access
Whenever feasible, our approach favors autogenous access, beginning with a distal radiocephalic AVF and progressing to more proximal options when necessary.
But preserving the most distal vessels is not the only priority.
An AVF that requires prolonged maturation, remains difficult to cannulate, or exposes the child to repeated interventions may not represent the best solution.
This is particularly relevant in pediatric patients, where the available time before transplantation, previous catheter exposure, and the child's physical development can substantially influence the treatment strategy.
The best access is not necessarily the most distal or technically sophisticated one. It is the access that becomes reliably usable and serves the child's clinical needs.
More than a surgical procedure
Pediatric dialysis access surgery requires close collaboration between vascular surgeons, pediatric nephrologists, dialysis nurses, children, and their families.
The operation itself may take less than an hour. Its consequences, however, can shape a child's dialysis treatment for months or years.
For children facing a long and sometimes difficult journey toward kidney transplantation, a reliable vascular access can make an important difference.
And occasionally, the most rewarding outcome is not a flow measurement or a patency statistic.
It is seeing a child smile.
Conclusion
The question “How small is too small?” cannot be answered by vessel diameter alone.
Successful pediatric vascular access requires careful patient selection, detailed ultrasound assessment, technical precision, realistic expectations, and an experienced multidisciplinary team.
Ultimately, the goal is not simply to create a patent AVF, but to provide a functional, reliable dialysis access for a child who needs it.
Based on my presentation at the 15th Cologne Home Dialysis Congress, April 24, 2026.
Dr. Vladimir Matoussevitch | VascularAccessTalk