I would like to discuss a few points raised by Troianos et al. in their recent thoughtful, well-researched report on ultrasound-guided vascular cannulation in JASE .
First, on page 1294, Troianos et al. state, “A limitation of the needle guide is that the needle trajectory is limited to orthogonal orientations from the SAX [short-axis] imaging plane.” However, needle guides oriented to the long axis are in fact commercially available (see Figure 1 ).
Second, on pages 1300 and 1301, Troianos et al. describe the visualization and cannulation of the infraclavicular subclavian (SC) vein:
“Ultrasound-directed vascular cannulation may lead inexperienced operators to use needle angle approaches that lead to an increased risk for complications. It is important that traditional approaches and techniques are not abandoned with ultrasound guidance, particularly during cannulation of the SC vein, in which a steeper needle entry angle may lead to pleural puncture.
Similar to the landmark technique, the middle third of the clavicle is chosen as the site used for ultrasound imaging and subsequent needle insertion. The transducer is oriented to image the SC vein in the SAX view with a coronal imaging plane. The vein appears as an echo-lucent structure beneath the clavicle (Figure 13).”
In discussing these points, I contend that the dominant vein in the infraclavicular fossa is the axillary vein, which does not become the SC vein until it reaches the lateral border of the first rib. Visualizing the subclavian vein in the SAX view is essentially impossible in most patients. The investigators’ Figure 13 labels the subclavian vessels. However, I believe it is the axillary vessels that are actually visualized (see Figure 2 ).
