A catheter assembly comprising: an elongated tubular structure having a distal end terminating in a distal end surface and a proximal end terminating in a proximal end surface a septum disposed within the interior of the elongated tubular structure so as to define a first lumen and a second lumen within the elongated tubular structure, wherein the septum comprises a distal end terminating in a distal end surface and a proximal end terminating in a proximal end surface, and further wherein the distal end surface of the septum terminates proximal to the distal end surface of the elongated tubular structure and the proximal end surface of the septum terminates.