Use of early scanning in fistula formation for vascular access

To determine the feasibility and role of early scanning in the assessment of arteriovenous fistulae fashioned for vascular access.

Retrospective case note analysis of 98 patients who underwent early scanning (between 7 and 28 days) of their fistula as well as routine scanning at 6 weeks over a 2-year period.

The median time was 16 days to the first scan and 51 days to the second scan. Only 1 fistula was unable to be assessed at the first scan. There were 73 normal first scans, 11 of these had an abnormal second scan showing 4 occlusions, 4 stenoses, and 3 with low flow. There were 25 abnormal first scans. Five were occluded with a mean time to scan of 16.7 days. Eleven of the 25 had a narrow vein. By the second scan, 6 had matured, 3 had occluded, and 2 had failed to mature. Nine of the 25 had low flow, elevated velocities, or a stenosis. By the second scan, 2 had matured, 4 had occluded, and 3 had failed to mature.

Our results show that early scanning in the surveillance of arteriovenous fistula formation for vascular access is both feasible and reveals a significant number of abnormalities. Early scanning does not remove the need for the routine 6-week scan.