What does blood flow rate (BFR) exceeding vascular access flow cause?

When blood flow rate (BFR) exceeds the vascular access flow, it leads to increased arterial pressure. This phenomenon occurs because the vascular access site, such as a fistula or graft, has a limited capacity to accommodate the flow of blood. When the BFR is higher than what can be effectively managed by the access site, it results in a buildup of pressure in the arteries supplying the access.

This increased arterial pressure can have several implications, such as the potential for complications at the access site, which may include stenosis or thrombosis if consistently high pressures are present. Maintaining an appropriate balance of BFR and vascular access capacity is crucial for ensuring optimal performance during dialysis sessions and for the long-term health of the vascular access.