Flow-directed Fistula Construction Autogenous arterial venous fistulas (AVFs) are the preferred method of vascular access. While they remain patent longer and exhibit fewer complications than AV grafts and catheters, they may not maturation. Intraoperative flow measurements at time of fistula construction can foreshadow successful maturation. Intraoperative AV Fistula Measurement Protocol
Flow-directed Fistula Banding Two conditions mandate the need to increase venous flow resistance through a high flow AV fistula used for hemodialysis. They include:
Clinical significant Hemodialysis Access-induced Distal Ischemia (HAIDI), a potentially devastating AV access complication that occurs primarily in diabetic ESRD patients. Banding relieves distal ischemia by increasing fistula resistance.
Cardiac Overload when fistula flow is so high that it places too much stress on the heart and endangers heart function. Banding increases fistula resistance, lowers fistula flow and reduces stress on the heart.
Flow-directed Prosthetic Vascular Access Graft Construction
Direct intraoperative flow
measurements on newly inserted prosthetic ePTFE grafts are not possible due to air in the ePTFE graft walls (air blocks ultrasound transmission). Therefore, arterial flow
into the graft is measured on the artery proximal to the arterial/graft anastomosis. If the distal artery is not ligated, distal arterial flow is occluded during
measurement. After construction of the graft/venous anastomosis, distal outflow is measured in the vein with proximal venous flow occluded, if the vein has not been
ligated. Full Medical Note >
