[When native arteriovenous fistula is not possible: the permanent catheter is better]

Native arteriovenous fistula is still the vascular access of choice in hemodialysis. Other options are arteriovenous graft or, in patients in whom it is not possible to create a surgical vascular access, a permanent venous catheter. International guidelines on vascular access for hemodialysis recommend an increase in the percentage of arteriovenous fistulas compared to other types of vascular access. An analysis of the data relative to the distribution of the types of vascular access in different countries highlights the difficulty in following this recommendation: the only country to have increased the number of arteriovenous fistulas in recent years is the US, where the percentage of grafts has decreased while the use of permanent catheters has increased. In Italy and the rest of Europe, the number of fistulas has remained stable, there has been a constant reduction in the number of grafts and an increase in the percentage of permanent catheters. The reasons for this distribution of the types of vascular access are multifactorial and include the increased average age of patients, frequent late referrals, and increased incidence of diabetes mellitus, cardiovascular disease, obesity, etc. These factors have brought about technical difficulties for the creation of fistulas and grafts, leading to an increase in the number of catheters used. In relation to the evolution of the clinical characteristics of dialysis patients, the permanent catheter should no longer be considered a last-choice vascular access: in selected patients, it can be a better choice than a surgical fistula or graft.