Apparatus for peripheral vascular access
This invention provides devices and methods for insertion of a catheter into a vessel. The devices include coaxial slidably mounted needle, dilator and catheter components. The methods include piercing a vessel with the needle component, dilating the pierced hole with the dilator component, retraction of the needle component, insertion of the catheter and withdrawal of the dilator.
1. A method of confirming placement of a catheter within a vessel, the method comprises:
providing a needle slidably mounted within a dilator, where the dilator is slidably mounted through the catheter and extends from a distal end of the catheter, where the needle is spring biased in a proximal direction against a retaining material to allow a piercing end of the needle to extend out of a distal end of the dilator;
advancing the piercing end of the needle through a wall of a vessel into a lumen of the vessel such that a fluid within the vessel travels through the needle to contact the retaining material causing weakening of the retaining material allowing proximal movement of the needle within the dilator such that the piercing end of the needle retracts into the dilator; and
advancing the catheter over the dilator into the vessel lumen.
2. The method of claim 1 , further comprising advancing the dilator within the lumen of the vessel after the piercing end of the needle retracts.
3. The method of claim 1 , further comprising removing the dilator from within the catheter.
4. The method of claim 1 , wherein the catheter is advanced into the vessel lumen before removing the needle from the dilator.
5. The method of claim 1 , wherein the piercing end of the needle retracts before the catheter is fully advanced into the vessel.
6. The method of claim 1 , further comprising providing a catheter body at the proximal end of the catheter, and providing rigidity along the needle at least from the piercing end to the catheter body.
7. The method of claim 1 , further comprising advancing the catheter within the vessel lumen after the piercing end of the needle retracts.
8. The method of claim 1 , wherein advancing the catheter over the dilator into the vessel lumen occurs prior to retracting of the piercing end of the needle into the dilator.
9. The method of claim 1 , wherein advancing the catheter over the dilator into the vessel lumen occurs after retracting of the piercing end of the needle into the dilator.
10. The method of claim 1 , further comprising trapping the fluid contacting the retaining material within a flash reservoir to prevent the fluid from leaking out of the flash reservoir.