A pre-slit cannula diaphragm is integrated into a peripheral venous catheter to provide a cannula ready intravenous catheter with a cannula chamber closed to the environment, thereby reducing the risk to health-care providers from blood borne diseases and the risk to patients from airborne hazards. The cannula ready intravenous catheter includes a cylindrical housing that provides an uninterrupted smooth surface, for reducing skin irritation. A proximal end of the cylindrical housing provides a luer-type connector site, and a distal end of the cylindrical housing provides a catheter hub. The catheter hub supports a catheter tube, which extends from a distal end of the catheter hub.
