Commencing cannulation of native arteriovenous fistulas in hemodialysis, after its construction, has become a challenge for nurses and nephrologists working in dialysis centers, and there are significant differences in medical practice in this regard.In the following study, we review the literature and the usefulness of ultrasound to help inform these decisions, and we propose a temporary classification for the beginning of the cannulation, after the construction of the native arteriovenous fistulas in hemodialysis, that could be of help for subsequent comparative studies.