I just started working in dialysis nursing last week, and today we were learning about venipuncture. Our instructor taught us to puncture with bevel up, pinching the butterfly wings between your fingers (in nursing school I heard multiple opinions about how best to hold a butterfly needle, and am not going to go into it here since I have seen no definitive evidence one way or the other about which is better). But after the practice time with the fake vessels and fake arms, we watched several videos, as well as a powerpoint presentation, and in both the powerpoint and one of the videos, there was substantial evidence to suggest that bevel down insertion does less damage to skin, superficial tissue, and - most importantly - the wall of the graft or fistula. When one of my coworkers asked the instructor why we don't learn bevel down instead, the instructor told us that this is just how we do it here. I was disturbed, because all through nursing school, I had the idea of evidence based practice crammed down my throat. You do things in a certain way because the evidence suggests this is the BEST way, not because this is the way it's always been done. But as a new employee (and even worse a new grad RN) I am hesitant to be too vocal in my stance on this unless I have an overwhelming preponderence of evidence to back me up. So I was wondering what the policies and procedures were elsewhere and whether others had found significant evidence one way or the other.
Think about it. Sticking with the bevel down means you have to start with steeper angle, and you have to level off quicker so the razor sharp bevel won't slice the bottom of the vessel. That being said, there are probably those that are very good at sticking that way because they learned through trial and error like the rest of us and became proficient. In my experience you will get a flash back sooner with the bevel up and won't have to worry as much about puncturing the top as you level off. As you DC the needle, you don't want to put much pressure on anyways until right at the end when the needle is just about out. Those rascals are sharp.
Last edit by diabo on Dec 14, '06
I'm currently training in an inpatient/acute hospital setting; my preceptor is doing some things that I don't agree with or even know are incorrect. But I'm not about to disagree with her or challenge her practice. Unfortunately, I learned this the hard way as a new grad... it's often best to go along with what you are taught (and in this case, there is no clear-cut evidence of which approach is best); later, when you are on your own, you can adjust your technique to what works best for you. (Since your company's own training video shows the approach that you think is best, they can hardly argue that what you are doing is wrong.)
In my experience - 5+ years in outpatient dialysis for a large company - far more damage is done to fistulas and grafts by repeatedly cannulating in the same area, i.e. failing to rotate sites (aneurysms, pseudoaneurysms, scarring, coring and shredding of the graft material). Sadly, this is often done because many workers are in a hurry and prefer to stick the tried and true sites (easy to find since they are often bulging) rather than take the time needed to cannulate new parts of the access.
HTH. Good luck to you!
P.S. I cannulate bevel up, I feel that it gives me better control (it's also how I was taught, BTW); I will then rotate the needle if needed and rotate it back before removal.
Last edit by DeLana_RN on Dec 15, '06