Wire-guided surgical instrument

1. A surgical instrument for advancement over a preinserted guidewire as used during performance of the Seldinger or modified Seldinger techniques, the surgical instrument comprising:

a rigid body having a proximal end, a distal end, a top edge, a bottom edge, a left side, and a right side,

wherein the top edge is opposite the bottom edge, and

wherein the left side is opposite the right side;

a blade having a cutting edge formed at the distal end of the body along the bottom edge of the body extending to a tip of the body, the cutting edge extending a length from the bottom edge of the body to the tip at a fixed angle,

wherein the tip of the rigid body and a tip of the blade end in close proximity to one another; and

a closed rigid cylindrical tube immovably affixed to only the top edge of the body at the distal end of the body in close proximity to the tip of the body,

wherein the closed rigid cylindrical tube is configured to be threaded over the preinserted guidewire by inserting the preinserted guidewire into a proximal end of the closed rigid cylindrical tube near the tip of the blade and the surgical instrument is advanced over the preinserted guidewire to a skin surface to perform a dermototomy incision during the Seldinger or modified Seldinger techniques using the cutting edge of the blade,

wherein the tip of the blade extends past a proximal end and a distal end of the closed rigid cylindrical tube, wherein the rigid body is configured to be encased within a scalpel sheath such that the rigid body is movable relative to the scalpel sheath between a closed position retracted within the scalpel sheath to an open position at least partially advanced relative to the scalpel sheath.

2. The surgical instrument of claim 1 , wherein a central axis of the surgical instrument, a central axis of the cylindrical tube, and a central axis of the blade are coplanar.

3. The surgical instrument of claim 1 , wherein the proximal end of the body comprises a handle.

4. The surgical instrument of claim 1 , further comprising:

the sheath surrounding the surgical instrument.

5. The surgical instrument of claim 4 , wherein the sheath comprises a first channel for accommodating a button attached to the surgical instrument.

6. The surgical instrument of claim 5 , wherein the button is used to move the surgical instrument from the closed position to the open position.

7. The surgical instrument of claim 6 , wherein the sheath further comprises a second channel for accommodating the cylindrical tube when the surgical instrument is in the closed position.