I bet everyone on PD makes that mistake at least once. I know I have several times.When I first got my catheter and it wasn't draining, I went in for an x-ray with dye to see where the catheter was. The people working on me weren't especially familiar with PD catheters, and they didn't know exactly how to hook up a syringe to it. They tried what should've worked - screwing the syringe (without a needle) into the end of the catheter, but the dye just wouldn't go in. After 40 minutes, a confused doctor, two confused nurses, and a confused dialysis nurse, I finally realized - no one had unclamped the line!