A catheter insertion device has a generally hollow housing having a closed base end opposite an open distal end. A hollow needle defines a channel in fluidic or pneumatic communication between a distal skin-piercing end and the proximal needle end. A plunger is slidably disposed over at least a portion of the hollow needle. The distal skin-piercing end of the hollow needle extends through the plunger distal end. An expandable chamber is at least partially formed by the plunger proximal chamber end and at least an inside surface of the closed based end of the generally hollow needle, where the expandable chamber is in fluidic or pneumatic communication with the channel of the hollow needle through the proximal needle end. The expandable chamber is configured to increase in volume as the plunger moves towards the distal skin-piercing end of the hollow needle.
