Ultrasound-guided central venous catheterization. Long-axis in-plane technique.

 In this technique, the needle is advanced inside the ultrasound scan plane while observing the long axis of the vein. Unlike the short-axis out-of-plane, puncturing is truly performed in real time. Although this technique can be applied clinically with the Internal Jugular Vein if a small probe is used, it can be difficult to use regular-sized probes on the necks of small adults due to lack of space to manipulate. This technique is particularly useful with the IAV. With the long-axis in-plane technique, penetration of both the anterior and posterior walls of the vein does not occur very often, but the needle may penetrate the vein if the needle is directed from the anterior wall toward one of the lateral walls. Depicting the long axis of the center of the vein can prevent a needle directed toward a lateral wall from penetrating the vein (Fig. 1).

Fig. 1 

Long-axis in-plane technique. To perform the procedure safely, the operator should identify the center of the vein using the scan called the “side-scape scan technique” , which includes the following steps: First, turn the distal part of the probe to the right until the right lateral wall is identified (the yellow arrow shows the turning direction). The lateral wall appears to have a bullet shape because of the merging of the anterior and posterior walls. Second, turn the distal part of the probe to the left, and the left lateral wall can then be identified. The operator can estimate the distal center of the vein and then repeat the same motion at the proximal side of the vein to estimate the proximal center of the vein. Third, the operator can obtain the longitudinal ultrasound view of the center of the vein. Finally, with the needle guide and/or personal skills, advance the needle within the ultrasound beam, which can prevent “anterior to lateral wall penetration.” 

read also: Ultrasound-guided central venous catheterization. Short-axis out-of-plane.