In an arteriovenous fistula, the venous needle should be placed in which direction relative to blood flow?

• A. Retrograde
• B. Lateral
• C. Posterior
• D. Antegrade

Answer: (D)

Placing the venous needle in the direction of blood flow toward the heart (antegrade) ensures the returned blood from the dialysis circuit moves with the natural venous flow. This minimizes recirculation of already dialyzed blood, helps maintain efficient dialysis, and reduces turbulence or trauma to the fistula. Cannulating opposite to flow (retrograde) can cause backflow and inefficiency, so the needle should be directed downstream along the flow.