How to make the axillary vein larger? Effect of 90° abduction of the arm to facilitate ultrasound-guided axillary vein puncture

PURPOSE: Placement of central venous catheters by the infraclavicular route can be achieved by ultrasound-guided puncture of the axillary vein. However, in some cases, the axillary vein may be difficult to puncture because it is too deep or too small or because it is collapsing significantly during breathing. The objective of this observational study was to determine the effect of 90° abduction of the arm associated with forward position of the shoulder on axillary vein diameters. MATERIAL AND METHODS: In a group of 30 healthy volunteers and in a group of 40 patients during spontaneous breathing, we used ultrasound to examine the axillary vein, visualizing it in short axis, with the arm at 0° and at 90° abduction, pushing the shoulder forward. RESULTS: The axillary vein was easily identified in 100% of subjects, with relevant variability in terms of depth from the skin, diameter, and tendency to collapse during inspiration. Significant increase of axillary vein diameters was found after 90° abduction in 52 of the 70 cases studied. CONCLUSION: These findings suggest that a 90° abduction of the arm, particularly if associated with a forward position of the shoulder, facilitates the visualization of the axillary vein, making its ultrasound-guided venipuncture easier.