Fig. 10.

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” [48], 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.”