Ultrasound-guided central venous catheterization. Short-axis out-of-plane.
Short-axis out-of-plane technique In this technique, the needle is inserted while observing the short axis of the vein; thus, the needle intersects the ultrasound image. It is mainly used for puncturing the IJV and FV. It is advantageous, because positional relationships with arteries are easy to identify, but its disadvantage is that it is difficult to know, where the needle is until it enters the beam plane of the ultrasound scan. In addition, distinguishing between the tip and the shaft of the needle by observing an ultrasound image can be difficult. Therefore, if the needle goes outside the scan plane and goes through the vein, the tip can possibly puncture an artery or the lung.