Percutaneous central venous catheterization can provide reliable temporary hemodialysis access. The current study compared the hemodynamic performance of 28 coaxial catheters to 27 side by side catheters. A total of 675 dialysis sessions were evaluated to assess the flow characteristics of these two designs. The results demonstrated that the side by side catheter provided greater cumulative blood flow with more favorable venous and arterial pressures. Nevertheless, the coaxial catheter performed satisfactorily and met the minimum standards for these devices.