Releasably locking introducer devices

A medical introducer device suitable for inserting a catheter or guidewire into a patient comprising:

• (a) a releasably locking dilator and sheath,
• the sheath having a bore adapted to receive the dilator and the sheath adapted to circumscribe the dilator,
• the dilator having a cross-sectional shape that enables axial rotation of the dilator within the circumscribing sheath;
• and
• (b) a component that can be operationally secured on the dilator with the dilator separated from the sheath,
• the component being capable of rotating independently of the dilator to releasably lock and unlock the dilator and sheath when the sheath circumscribes the dilator and without relative axial rotation of the dilator and sheath, and
• the component completely circumscribing the dilator.

A method for inserting a catheter or guide wire into a patient comprising:

• (a) providing an introducer device comprising a releasably locking dilator and sheath,
• the sheath having a bore adapted to receive the dilator, the sheath circumscribing the dilator,
• a component that completely circumscribes the dilator, the component releasably locking and unlocking the dilator and sheath components and can be operationally secured on the dilator with the dilator separated from the sheath;
• (b) inserting the distal end of the device into a patient while the dilator and sheath are releasably locked;
• (c) rotating the rotatable dilator component with respect to the dilator longitudinal axis to unlock the dilator and sheath;
• and
• (d) withdrawing the dilator from the sheath and inserting a catheter or guide wire through the sheath into the patient.

A method for introducing a catheter or guide wire into a patient comprising:

• (a) providing an introducer device comprising a releasably locking dilator and sheath, the sheath circumscribing the dilator, the dilator having a non-circular shape for essentially the entire dilator length and which inhibits rotation of the dilator within the circumscribing sheath;
• (b) inserting the distal end of the device into a patient while the dilator and sheath are releasably locked;
• and
• (c) withdrawing the dilator from the sheath and inserting a catheter or guide wire through the sheath into the patient.