We thank Moy and Keeyapaj1 for highlighting an important element of successful ultrasound-guided peripheral vascular access in obese patients. Although we did not report it, we used a 1.77-inch (45-mm) catheter as the standard length for our study.2 Notably, even with a longer catheter, catheter displacement occurred during arm positioning in one study patient. After this event, we started to use a 5.25-inch (133-mm) length catheter (Becton Dickinson Infusion Therapy Systems Inc, Sandy, UT) for a target vein depths >15 mm. Precisely as described by Moy and Keeyapaj,1 there is a greater chance of unrecognized catheter dislodgement and infiltration when a deep vein is cannulated in obese patients, even with a longer catheter. Therefore, it is necessary to image agitated fluid (microbubbles) in the vein distal to the cannulation site using ultrasound after positioning patients’ arms to confirm continued intravascular placement of the catheter.