Ok, this is what I think happened, and the reason for this is, it has happened to me when I used to use the wings to cannulate. As you reached accros with the sharp needle, you bypassed the vessel and slid down the side. That is why you did not get any return. The MAIN PROBLEM WITH USING THE WINGS is that every time you use a sharp needle, you cut a new track. This is what I recommend and do in clinic and for some patients who do home dialysis and have upper arm fistulas. Use a TV tray you can get at Walmart. Place a pillow or cushion that is stiff on top of the tray and rest your forearm on it. Using “TOUCH CANNULATION,” place the base of your palm on your arm to cannulate. That way, every time it is the same. Look at the webinar “Touch Cannulation” on homedialysis .org. This has worked. Make sure you practice before you start .