SELDINGER TECHNIQUE

Seldinger technique is the building block of Interventional Radiology and other percutaneous modalities. It is how access is created for catheters and drains. This method is used all over the body for central lines, arterial and venous access, and organ and fluid drain placement. 

Prior to the Seldinger Technique, large bore needles were placed directly into arteries causing a high rate of complications.

Technique

The principal of this technique is to start with a small access needle and gradually size up to the access you need to perform a procedure or place a drain.

Steps

• The desired vessel or drain location is accessed with a small hollow needle. In IR, this is mostly done with ultrasound guidance.
• A soft, angled wire will then be placed inside the needle to hold access to the desired location. 
• While keeping the guide wire in place, the needle is removed.
• A catheter or sheath is placed on the back of the wire, and enters into the lumen of the vessel or cavity.
• The guide wire is then removed, leaving the sheath, drain, or catheter inside the lumen or cavity to allow other medical devices to be introduced.

Example

A micropuncture access kit is the simplest form of this.

It has a 21 gauge hollow needle, an .018 wire, and a 4F or 5F catheter. This is for access mostly because it does not have a side port or one way valve on the back.

These are the steps.

• Use ultrasound guidance to locate the artery or vein.
• Numb the area that you are going to access down through the tissue and superficially.
• Make a small incision if necessary
• Place the needle through the small incision and put the ultrasound in place.
• With guidance, the needle goes into the vessel and you see blood return.
• Place the wire through the needle.
• Remove the needle from the wire.
• Place the micropuncture sheath over the wire and into the vessel.
• Once the catheter is in place, remove the wire and inner dilator.
• A larger .035 wire is placed inside the micropuncture catheter.
• The micropuncture catheter is removed over the wire and replaced with a sheath for arterial or venous access.

Lesson Summary

The Seldinger Technique is a crucial method used in Interventional Radiology and other percutaneous procedures to create access for catheters and drains. This technique is used for various purposes such as central lines, arterial and venous access, and organ and fluid drains.

The principal behind the Seldinger Technique is to start with a small access needle and gradually increase the size to perform a procedure or place a drain. Here are the steps involved:

• Access the desired vessel or drain location using a small hollow needle, usually with ultrasound guidance.
• Insert a soft, angled wire through the needle to hold access to the desired location.
• Remove the needle while keeping the guide wire in place.
• Place a catheter or sheath on the back of the wire, which enters into the vessel or cavity.
• Remove the guide wire, leaving the sheath, drain, or catheter inside the vessel or cavity to allow other medical devices to be introduced.

A micropuncture access kit is a simple form of the Seldinger Technique and includes a 21 gauge hollow needle, an .018 wire, and a 4F or 5F catheter. This kit is primarily used for access without a side port or one-way valve.

Here is a brief summary of the steps involved in the Seldinger Technique:

1. Use ultrasound guidance to locate the artery or vein.
2. Numb the area if necessary and make a small incision.
3. Place the needle through the incision and into the vessel with ultrasound guidance.
4. Insert the wire through the needle.
5. Remove the needle from the wire.
6. Place the micropuncture sheath over the wire and into the vessel.
7. Once the catheter is in place, remove the wire and inner dilator.
8. Place a larger .035 wire inside the micropuncture catheter.
9. Remove the micropuncture catheter over the wire and replace it with a sheath for arterial or venous access.