bevel up or down?

  1. 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.
  2. Visit majestix profile page

    About majestix

    Joined: Dec '06; Posts: 11


  3. by   KnoxWarEagle
    First of all, What is substantial? Was this noted in a reputable journal with a substancial study group (ie: 12 is not substancial)? Over how long was the study and did the p value suggest reproducability? Never go against the grain without the proper tools. I am very open to ideas as long as there is evidence noted. Butterflys were designed for a bevel-up approach due to the angle. If you go in at a 45 degree angle and adjust to a lower degree you would dissect the vein in a bevel down position. This is just what I was taught. Advances are made through questioning. Keep the questions coming and let us know the answers!
  4. by   majestix
    The evidence was in the visible damage to graft material from various causes: bevel up, bevel down, bevel sideways, and applying pressure too soon when withdrawing. The tearing/holes from the bevel down approach were noticeably smaller than those from the bevel up approach. Also, it was mentioned briefly in one of the training videos. I don't remember the exact phrasing, but the description made me feel surprised that we use the bevel up approach instead. Since I only learned of this today, I obviously have not yet looked up the research. Hence the reason I am asking those who are in this field and likely have way more experience and knowledge of this subject to draw upon.
  5. by   Hellllllo Nurse
    A lot of dialysis units just do things the way they do them, and don't keep up with new research. Whatever the unit's policy is, that's the best way to keep from getting in trouble.
    FMC units have been showing the bevel down film for years, and they all cannulate bevel up, for some reason.
  6. by   diabo
    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
  7. by   nursedandy
    In our facility we experienced that when we cannulate bevel down, there is less bleeding after we remove the needles.
  8. by   DeLana_RN
    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
  9. by   traumaRUs
    What about button-holes? I know in some of our outpatient units, our patients prefer the button-holes and self-stick.
  10. by   DeLana_RN
    Quote from traumaRUs
    What about button-holes? I know in some of our outpatient units, our patients prefer the button-holes and self-stick.
    The buttonhole technique is the best method for cannulating a fistula, which has been used in Europe for years. However, too few units currently teach or practice it in the U.S.

    In a nutshell, with the buttonhole technique you want to cannulate the same arterial and venous site over and over. After creating a "tunnel" with a sharp needle (specially trained RNs teach the patient or staff members how to do this), the patient (or staff member) carefully removes the previous scab and then inserts a special blunt needle in the same track for each dialysis treatment; this prevents infiltrations or other damage to the fistula.

    One can only hope that this will become a more commonly used method in the future. It is excellent for home hemodialysis, but can also be used in the clinic setting.

    Whether or not the buttonhole technique is used, all patients should be encouraged to cannulate their AVF or AVG themselves; however, few choose to do so. More education by staff could improve these numbers. Patients who self-cannulate are usually happy to do so (and so are the staff: nobody can blame them for any missed stick ).

  11. by   penem10
    Cannulation Camp: Basic Needle Cannulation Training For Dialysis Staff by Deborah J. Brouwer, RN, CNN I highly recomend this inservice, she does cannulation training around the country.

    In her education materials she states "The needle should be held by the wings, with the bevel of the needle facing upward for the cannulation. This places the cutting edge of the needle on the skin, which facilitates cannulation through the skin, subcutaneous tissue, and the graft wall or fistula vessel wall."

    I would like to add that increasing evidence from Europe has substantiated that the buttonhole technique is a better technique because it creates a track in the vessel (for fistulas only) and cuts down on infiltrations. This can be done inhouse or for home based patients. Our facility does not use this, but I am thinking about pushing the issue.

    Robin A. Clark, RN, CDN