probably a dumb question about PIVs and drawing blood...

  1. 0
    hey- i'm a new grad, working in a picu...i had some issues for my first 2 months with an impatient and rather harsh preceptor who was more likely to say, 'why aren't you understanding this??' than to actually help me learn...so, for that reason, and others, i'm not where i (or my manager) want me to be; i'm still quite short on certain skills i haven't done, but i'm also sometimes working with preceptors who have that same incredulous attitude when i tell them i'm not familiar with a procedure. all that is background for my question...

    i had to draw blood on a teenager who didn't have a working arterial line (where i usually draw blood). so i had to use an antecubital PIV that had MIVF running through it. i knew i had to disconnect the maintenance fluid, waste some blood, draw off my sample, give the waste back, and flush. the IV had a luer-lock positive pressure cap on it. my preceptor told me to use a tourniquet above the site. i don't understand the logic here...if i shut off my fluid, took off my waste, then got the sample, why did I need a tourniquet? i got a look that said i was just a complete moron for not knowing...but i'm not a moron, i've just never had to do it this way before. the only thing i can think of is that the cap was *not* a luer-lock, and I'm misremembering.

    what am i missing here?
  2. 22 Comments so far...

  3. 0
    You would use the tourniquet in this instance for the same reason you would need a tourniquet for a regular peripheral blood draw; to slow the venous return, allowing the vein to fill up or become congested with blood. When you're drawing from a line like this, sometimes you need the tourniquet, sometimes you don't- i.e., if you're drawing from an 18 in the AC (a large bore IV in a large vein), you probably wouldn't need to bother with the tourniquet. But if you're drawing out of a 20 or 22 in the hand, you're probably going to have a hard time getting the blood unless you use a tourniquet. Next time you have to do this, try with the tourniquet and without; you should be able to see/feel the difference in how it is easier to get your spec when you've plumped up the vein with the tourniquet.
  4. 0
    hello i'm not a Peds or a PICU RN so I guess this might sound dumb to those that are....But with a running IVF, it's allowed to draw blood samples from the same site as where the peripheral IVF is running? I always thought that there's higher chance of hemolysis among other things that's why we're told not to draw blood from existing peripheral IV's...I mean I do work with alot of 18 or 16 g PIV's with IVF's, r u telling me I've wasted my time sometimes having to stand there with a butterfly looking for the last vein of a hard stick patient when I could have just as easily drawn it from the PIV? I mean yes during insertion I can draw prelim labs but after that I've always thought it was vein sticks...I'm just wondering
  5. 0
    In the ER, we do almost all of our lab draws from their lines, even if they have IVF runinning. I just shut off the fluid for about 5 minutes and draw off a waste before my labs. (*There are exceptions though-can't draw your PTT from a line that's been infusing Heparin. I wouldn't draw a K level if the IVF had K added or a Dig level if I had pushed Dig recently. And NEVER draw a glucose from a line you've pushed d50 through-that glucose likes to stick to the inside of the tubing of your heplock and could give you an erroneous reading. But just use common sense in situations like this) As a general rule, if a patient has a line, we don't stick them again for repeat labs, serial troponins, etc.
  6. 0
    Interesting, something new to learn from everyday I suppose, since I work in an environment where patient's almost always have CVC or an Aline, I guess all the years I've worked in the ICU setting, I've never seen one ICU nurse draw blood from a PIV with a mintenance IV going, nor from a hep lock...Personally I would frown if I see someone do this, but mainly because probably of lack of knowledge from the standard of practice that's used in different places in the hospital. Now my question is, for the other ER nurses out there....Is this done in your ER? And for the floor nurses and ICU nurses....Are these done in your unit? What's the thinking behind doing this as oppose to having nurses stick patients then if the patient has a hep lock with a large gauge for drawing labs...Keeping in mind that there is backflow from that heplock....I'm sorry did I just learn to be a good phlebotomist out of a myth? ALL responses would be appreciated.
  7. 0
    Think a minute. When a patient is receiving t-PA, you normally put in an extra IV that you can use for drawing labs from. That way that do not bleed all over when you need to draw labs from them. At least that is what I have always done.

    It is actually done all of the time, and especially in the ER. That is where I initially trained.........not every patient needs or requires an A-line. Drawing from the IV is not any different from drawing from a CVL.
  8. 1
    Hi there - I'm a float to medical, surgical, postpartum, and peds, and we never draw out of a peripheral IV unless it's when we are starting a new peripheral, before fluids have infused or meds have been given per that site. I guess we would only do so if absolutely desperate, ie no veins for even a poke with a butterfly. We have good phlebos, so I haven't seen that situation yet. It's against the floor protocols at my facility to draw from peripherals for routine labs. If it was absolutely necessary, I would definitely shut off fluids for 10-15 miutes first, waste, and then draw my sample (with the exceptions for labs like another poster listed above.) I suppose they are just trying to save the peds pt additional pokes in this instance? I think in the ER it would be a different situation. Just my experiences. . .
    DeLanaHarvickWannabe likes this.
  9. 0
    Again like I said something new to learn, thanks suzanne, but I work in a place where there is a Cath lab able to do PCI's all the time, so the use of TPA is not readily used much. I know blood is blood and it's on the vein so I'm pretty sure yes I do know that is blood and that is common sense....What I'm saying is there have been alot of publications about reasons why using a hep lock or someone with a MIVF is not a good idea. So then it's common practice not to use butterfly? to draw labs? I mean I would still not think of drawing cultures from PIV's but I'm not sure why not yet. I guess I'm just waiting for responses as to why I could, mainly because of the things that I've learned before...You can't teach an old dog new tricks i suppose....well not as easy anyways...
  10. 0
    Quote from hrtprncss
    Interesting, something new to learn from everyday I suppose, since I work in an environment where patient's almost always have CVC or an Aline, I guess all the years I've worked in the ICU setting, I've never seen one ICU nurse draw blood from a PIV with a mintenance IV going, nor from a hep lock...Personally I would frown if I see someone do this, but mainly because probably of lack of knowledge from the standard of practice that's used in different places in the hospital. Now my question is, for the other ER nurses out there....Is this done in your ER? And for the floor nurses and ICU nurses....Are these done in your unit? What's the thinking behind doing this as oppose to having nurses stick patients then if the patient has a hep lock with a large gauge for drawing labs...Keeping in mind that there is backflow from that heplock....I'm sorry did I just learn to be a good phlebotomist out of a myth? ALL responses would be appreciated.

    Having currently been in the ER for almost 2 yrs, we have always drawn initial labs from PIV that we started and had not flushed yet... It is however against our policy to draw blood from a line that has received IVF or any type of medication through it d/t having mismatched labs so frequently (we were doing cardiac enzymes and Troponins on our own machine in ER vs our lab techs drawing blood and running on their machines) At times there was a significant difference, so our policy changed to this. I'm sure every facility has their own, but this seems to be working well for us.... Hope I helped, It's probably clear as mud!!!! lol....
  11. 0
    Quote from hrtprncss
    Again like I said something new to learn, thanks suzanne, but I work in a place where there is a Cath lab able to do PCI's all the time, so the use of TPA is not readily used much. I know blood is blood and it's on the vein so I'm pretty sure yes I do know that is blood and that is common sense....What I'm saying is there have been alot of publications about reasons why using a hep lock or someone with a MIVF is not a good idea. So then it's common practice not to use butterfly? to draw labs? I mean I would still not think of drawing cultures from PIV's but I'm not sure why not yet. I guess I'm just waiting for responses as to why I could, mainly because of the things that I've learned before...You can't teach an old dog new tricks i suppose....well not as easy anyways...
    If drawing cultures from an existing line, then you would be culturing the line.
    Much depends on the patient and the state of their veins. With children we can actually just poke a finger and use a microtainer. In the field of peds, we use butterflys all of the time for drawing labs. Also, depends on what the test is...........in many chemo patients, and others that need blood to be drawn frequently, you will see a second line for taking blood from.


Top