Abstract: This invention relates to a medical device (20, 40, 60) for use in aiding the successful placement of a needle tip in a blood vessel. The medical device comprises a resiliently deformable collapsible body (21) defining a pressure chamber therein. The body further comprises a port (29) for engagement of a hub of a needle, the port defining a fluid passageway from the exterior of the body to the interior of the pressure chamber. The device further comprises means to generate an audible noise (31, 41) upon expansion of the collapsible body from a collapsed configuration to an expanded configuration. In this way, as the tip of the needle enters the lumen of the blood vessel, the collapsible body is configured to transition from a contracted to an expanded configuration, thereby causing the auditory cue. This auditory cue indicates to the medical professional that the tip of the needle is in the lumen of the blood vessel.