I have been using blunt needles since I started daily dialysis about 3 years back. To start with I never had any pain. But as I wrote here and here, I started having problems with the buttonhole technique about a year after I started using it.
I also created another pair of buttonholes as suggested on the home dialysis forums. Again, it worked really well for a few weeks. For the last few weeks, however, the pain has returned. It usually starts a few hours into the dialysis session. I wake up due to it. I then try to press the skin around the needles, fold the area around the cannulation sites and get a little relief. Then, I go back to sleep again.
I decided yesterday to do the unthinkable! Switch back to sharps! Yes, I can hear the ayatollahs of buttonholing yell:
"No, you don't want to do that!"
"How could you, possibly?"
"Are you out of your mind?"
"How can you possibly have pain with blunts? They are blunt, remember?"
Well, I switched to blunts yesterday. And, guess what? I had NO pain. Yes, absolutely NO pain!
I has an uninterrupted night of sleep. And, I repeat, NO pain.
So, there. It goes to show that everyone is different. I am NOT insinuating that the buttonhole method is flawed in any manner. No, not at all. It worked great for me for months. There was a time when if I looked the other way when my tech cannulated me, I wouldn't even realize that the cannulation was done!
But, after a while, it did not work as well. It could also mean that I was doing it the wrong way. And that is why I had problems with it. One more theory is that while sleeping, I tend to turn to the left (the side my fistula and the needles are). This could potentially cause some movement of the needles and they might touch the walls of the artery and the vein due to which I am experiencing pain.
Whatever it is, I am planning to use sharps for a while and see how it goes.