The present invention relates to a catheter securement device and securement device assembly for a securing a catheter relative to a patient. The securement device includes a base having an opening configured for receipt of the catheter, a cover member configured with the base over the opening, and a lip configured around at least a portion of the base. The base is configured for attachment to a patient's skin over a catheter insertion site and includes a top surface and a bottom surface, The opening of the base is configured to accommodate a catheter inserted therethrough from the catheter insertion site. The cover member is movable from an open position to a closed position over the catheter insertion site and is configured to secure the catheter. The lip is configured on the bottom surface of the base around the opening such that the lip reduces leakage from the catheter insertion site when the securement device is secured to the patient's skin.
