A surgical instrument for administering fluids and having a vessel entry indicator to confirm proper placement of the surgical instrument within the vessel includes a vessel access member adapted for accessing a blood vessel and having insertion and trailing ends. The access member defines a primary lumen for administering fluids to the blood vessel and a secondary lumen. A pressure detector is in fluid communication with the secondary lumen. The pressure detector is adapted to detect pressure associated with a disposition of the insertion end of the access member in the blood vessel. The access member may define a port adjacent the leading end and in fluid communication with the secondary lumen. In one embodiment, the secondary lumen is independent of the primary lumen. The pressure detector may include a float valve responsive to pressure of blood entering from the blood vessel through the port and into the secondary lumen. In the alternative, the pressure detector includes a pressure gauge. The pressure gauge is adapted to register pressure associated with a presence of blood entering from the blood vessel through the port and into the secondary lumen.