Effect of arteriovenous fistula for hemodialysis on limb circulation

The number of patients with end-stage renal disease maintained on chronic hemodialysis is increasing progressively. Arteriovenous fistula (AVF) is a common vascular access for hemodialysis, however, its effect on limb distal circulation has not been studied well. Palpation of pulse at the wrist is a crude method of clinical assessment. Over one year period, 26 AVFs were created; 16 at the wrist (61.5%) and ten fistulas at the elbow (38.5%). Six of the latter were through the brachio-basilic approach while the other four were performed by basilic vein transposition. Doppler measurement of both wrist-brachial index (WBI) and finger pressure was carried out for all patients pre-operatively and on the first post-operative day. Of the patients with AVF created at the elbow, there was a decrease of WBI in seven patients (70%) and a decrease of finger pressure in three (30%); one patient (14%) had steal syndrome. Creation of AVF at the wrist resulted in a decrease of WBI in one patient (6.25%) and a decrease of finger pressure in another patient (6.25%). WBI changes as a result of creation of AVF at the elbow were significantly greater than the changes of those fistulas performed at the wrist (P < 0.001). On the other hand, the difference between the effect of both procedures on finger pressure was statistically not significant. These results may help to explain the higher incidence of steal syndrome in patients with elbow fistulas compared to patients with wrist fistulas. Further studies on a larger scale are required to determine the value of non-invasive indices at which AVF creation would have future risk of compromised distal limb circulation.