Methods and devices for vascular access
Methods and devices to facilitate positioning of a catheter into a vessel. Devices include axially concentric assemblies of a piercing needle and a dilator that guides an outer catheter into a vessel, such as a blood vessel. The assemblies described herein can include retraction mechanisms and/or lock mechanisms to control needle positioning during catheterization processes as well as improved valves that prevent leakage of fluid from the proximal end of the devices. The devices and method include the use of novel valves to prevent undesired leakage of fluids through the proximal end of the catheter.
1. A catheter assembly for use with a male luer having a distal end and a lateral surface, the male luer having a connector portion, the catheter assembly comprising:
a catheter hub having a chamber and having a proximal-most surface defining an open proximal end;
a catheter tubing coupled the catheter hub and having a lumen in fluid communication with the chamber;
a septum valve comprising:
a barrier layer at a far end of the septum valve;
a wall portion extending proximally from the barrier layer towards a near end of the septum valve, the wall portion defining a valve cavity therein, the barrier layer extending perpendicularly to the wall portion at the far end, at least one slit extending through the barrier layer forming a plurality of leaflets in the barrier layer;
a flange portion at the near end of the septum valve, the flange portion having a diameter greater than a diameter of the wall portion, and where the valve cavity has an open proximal end;
the septum valve is coupled to the catheter hub such that the flange portion engages the proximal-most surface of the catheter hub exterior to the chamber and the wall portion engages a surface of the chamber; and
wherein insertion of the male luer into the open proximal end of the valve cavity causes the distal end of the male luer to open the at least one slit and separate the plurality of leaflets, while the lateral surface of the male luer engages the wall portion at an interior of the valve cavity causing the wall portion to engage the surface of the chamber, and where the connector portion directly engages the flange portion against the proximal-most surface of the catheter hub.
2. The catheter assembly of claim 1 , wherein the flange portion of the septum valve is affixed to the proximal-most surface of the catheter hub and where the wall portion of the septum valve contacts the surface of the chamber of the catheter hub.
3. The catheter assembly of claim 1 , wherein a perimeter of the at least one slit is limited to the barrier layer such that the leaflets do not extend into the wall portion.
4. The catheter assembly of claim 1 , wherein the at least one slit is branched such that the plurality of leaflets comprises at least three leaflets.
5. The catheter assembly of claim 1 , wherein an entire outer surface of the wall portion contacts the surface of the chamber.
6. The catheter assembly of claim 1 , wherein an entire outer surface of the wall portion comprises a cylindrical shape having a uniform outer diameter.
7. The catheter assembly of claim 1 , wherein a thickness of each of the plurality of leaflets is the same.
8. The catheter assembly of claim 7 , wherein the plurality of leaflets are located at the far end of the septum valve such that separation of the plurality of leaflets caused by insertion of the male luer causes the plurality of leaflets to deform out of the valve cavity.
9. The catheter assembly of claim 1 , wherein the septum valve is located within the chamber.
10. The catheter assembly of claim 9 , wherein a length of the chamber is greater than a length of the septum valve.