A delivery device for delivering an instrument into a catheter assembly may include a syringe, which may include a barrel and a plunger movable within the barrel. The plunger may include a handle and a stopper coupled to a distal end of the handle. The stopper may include a channel. The delivery device may include a guidewire disposed within the barrel and extending through the channel. In response to depression of the plunger, the guidewire may move through the channel and a first end of the guidewire may be advanced in the distal direction. A second end of the guidewire may be fixed.