Reuse prevention safety catheter

1. A reuse prevention safety catheter, the catheter comprising:

a catheter hub having an external needle disposed on the catheter hub;

a cannula plug having an internal needle insertable and penetrable into the catheter hub and disposed on the cannula plug to introduce the external needle into a blood vessel and to be separated from the catheter hub; and

a locking guide unit having a through-hole configured to allow the internal needle to pass through,

wherein the through-hole is deformed when the internal needle is withdrawn, such that re-penetration of the internal needle is blocked,

wherein the locking guide unit comprises a first locking guide and a second locking guide, each of the first locking guide and the second locking guide having a truncated conical shape with an eccentric center of gravity and configured such that when the internal needle is withdrawn from the through-hole, an inclination in the first locking guide and the second locking guide is generated within an angular range of greater than 0° and less than 90° by gravity to change a position of the through-hole,

wherein the first locking guide and the second locking guide each have a gradually decreasing diameter at respective ends of the first locking guide and the second locking guide, and

wherein the second locking guide is located distal to the first locking guide, and the first locking guide and the second locking guide are symmetrically disposed with the respective ends of the first locking guide and the second locking guide opposite each other so that when the internal needle is first withdrawn from the second locking guide, the end of the second locking guide is lowered so that a symmetrical disposition becomes a staggered disposition and a path of the through-hole is changed.

2. The catheter of claim 1 , further comprising:

a slide casing configured to be extended from the cannula plug to cover the internal needle,

wherein the locking guide unit is disposed at a front end part of the slide casing.

3. The catheter of claim 2 , wherein the slide casing comprises a holder configured to be hooked by a finger to enable a user to separate the cannula plug from the catheter hub, wherein the locking guide unit is disposed in the holder.

4. The catheter of claim 1 , further comprising:

a blood blocking unit disposed in the catheter hub to block backflow of blood.

5. The catheter of claim 1 , wherein the locking guide unit is an injection-molded part independent of the cannula plug and maintains a locked state in the cannula plug by the internal needle, wherein when a locking force is removed as the internal needle is withdrawn, the inclination is generated in the locking guide unit, such that the position of the through-hole is changed.

6. The catheter of claim 1 ,

wherein a locking force of the first locking guide and the second locking guide is removed when the internal needle is withdrawn, such that the inclination is generated in the first locking guide and the second locking guide, respectively, and a longitudinal hollow path formed by the through-hole of the locking guide unit is collapsed by misalignment of the first locking guide and the second locking guide.

7. The catheter of claim 1 , further comprising:

a spring providing elastic force pushing the cannula plug from the catheter hub,

wherein the spring pushes the cannula plug from the catheter hub to completely extend the internal needle from the locking guide unit.