[20 years' experience with "difficult" vascular access].
The increased survival of patients in dialysis and the gradual increase in the age of uremic patients commencing chronic dialysis raises serious problems for the creation and maintenance of efficient vascular access. In cases in which it is extremely difficult to create arteriovenous fistulas (AVF) using existing upper limb veins, it is possible to resort to vascular grafts, lower limb AVF, central venous catheters or refer the patients for peritoneal dialysis if this method is technically possible. In order to evaluate the incidence of these phenomena in quantitative terms, the authors have made a retrospective analysis of patients undergoing vascular access surgery since the opening of the Dialysis Centre on 1/9/1973 to 30/9/1996. During this period (277 months) a total of 1,037 AVF implant operations were performed (in addition to 65 arteriovenous shunts in the earlier period and 28 permanent central venous catheters in the last 10 years). The survival of AVF grafts was lower than that in natural vessels in 384 patients without clinical risk. In diabetic subjects, those suffering from vascular pathologies, systemic diseases, or aged over 70, the survival of AVF was distinctly lower compared to the group without these risk factors. However, the higher risk group did not show any marked difference in survival between AVF in the patient's own veins and grafts. In only 4 out of 1,037 operations it was impossible to obtain vascular access in the upper limbs (2 patients were referred for peritoneal dialysis and AVF were executed in the thigh in 2 patients). In conclusion, the retrospective analysis of this series leads the authors to affirm that the rational use of natural vascular accesses normally allows a sufficient operating margin; however, in special cases suitable techniques (such as permanent central venous catheter or AVF in the thigh) can enable difficult situations to be resolved as an alternative to peritoneal dialysis.