Hemodialysis patients may develop distal ischemia in an extremity harboring a functioning arteriovenous access (AVA). Surgery is indicated if conservative treatment including catheter-based therapies fails. The role of surgical banding for refractory hemodialysis access-induced distal ischemia (HAIDI) is systematically reviewed (n=39 articles). If banding is executed without an intraoperative monitoring tool ("blind"), or guided by finger pressures only, clinical success and access patency rates are low (<50%). In contrast, banding is clinically successful when access flow is monitored during the operative procedure, with excellent long-term patency of banded AVA's (97%, 17 +/- 3 months). Banding is the method of choice in HAIDI patients with a normal or high access flow (>1.2 l/min) provided that flow and distal perfusion are closely monitored intraoperatively.

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The elbow fistula has a long patency with few complications and performs as well as wrist fistulas and better than the graft fistulas reported in the literature. The Gracz elbow fistula has results as good as the side-to-side elbow fistula. Graft fistulas should be reserved for tertiary procedures only.

A time-dependent resistance model is used to study haemodynamic aspects of haemodialysis treatment. In the first part of the paper one model circuit, consisting of a pressure source, upstream and downstream resistances and a branching resistance, is shown to represent the haemodynamics of any type of arteriovenous fistula (AVF). Simple algebraic relations are derived for the haemodynamic determinants of AVFS, including finger ischaemia and AVF-maturation. The second part of the paper analyses the influences of a two-needle extracorporeal dialysis (ECD) circuit on the systemic vascular haemodynamics. The main result of the analysis is that the ECD-circuit can be considered as virtually independent of the systemic circulation. Consequently the dialysis flow does not depend on systemic vascular determinants and there are no instantaneous changes in the systemic circulation after switching on the ECD circuit. The ECD flow at onset of AVF collapse is shown to be (slightly) larger than the undisturbed AVF flow. Hence, onset of collapse strongly depends on the systemic blood pressure and vascular resistances. It can be used diagnostically to assess AVF capacities. Optimisation of haemodialysis through the ECD circuit is predicted to be inefficient.

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