An introducer apparatus and a method for forming an introducer apparatus. The apparatus comprises an inner liner having a passageway extending longitudinally therethrough. A coil in a stressed, radially expanded condition is positioned longitudinally around said inner tube. A polymeric outer tube is positioned longitudinally around the coil and the inner liner, and is bonded to the inner liner through the spaces between the turns of the coil. The polymeric outer tube is formed in a manner such that it maintains the coil in its stressed radially expanded condition. In a preferred embodiment, the inner liner and outer tube comprise a polyimide.