Humming Is as Effective as Valsalva's Maneuver and Trendelenburg's Position for Ultrasonographic Visualization of the Jugular Venous System and Common Femoral Veins

All 3 maneuvers distended the external jugular, internal jugular, and common femoral veins compared to baseline. There was no important difference in magnitude of cross-sectional area between any of the 3 maneuvers when compared with one another. Humming shares many physiologic similarities to Valsalva's maneuver and may be more familiar and easier to perform during procedures such as ultrasonographically guided central venous catheter placement and insertion of external jugular intravenous catheters.