Radial artery access is the first step in performing an endovascular procedure using the radial artery. Despite its intuitive similarities to other access sites, there are several important unique aspects of obtaining and managing radial access that merit mention.
Radial Artery Puncture
The small diameter of radial artery lumen, in conjunction with the thicker wall, creates a combination that increases the likelihood of failure because of non-coaxial entry and hence, difficulty with guidewire advancement. This is compounded by the lack of anchoring of the radial artery to the surrounding tissue, making it very prone to displacement in response to tangential force. These attributes are what make radial artery puncture a technically challenging part of the procedure and constitutes a large portion of the initial learning curve.
Unlike femoral access, a micropuncture needle, usually 20-gauge, is recommended for successful lumen entry. Using a modified Seldinger technique, a 0.018” or 0.021” micropuncture guidewire is placed into the arterial lumen. Stainless steel or nitinol guidewires are available, and polymer-jacketed versions may be used as well.