Questions about IV Meds

[RN/Mom]

I'm a 4th semester RN student in the middle of my med-surg rotation, and I've run into a few different situations in clinical in the past few weeks where I am wondering the "right" way to do something and no policy seems to exist. I am curious to hear how other nurses handle these situations in real life, so I figured this is the perfect place to ask! :)

First, there was a situation where there were multiple IV push meds ordered for a pt with a double lumen PICC line receiving a heparin drip through the medication port (she didn't have any other IV access). What I ended up doing was stopping the heparin drip for over ten minutes, detaching it from the medication port, flushing the line, pushing the meds (flushing again after each one was given of course), and then reattaching and restarting the heparin drip. It seemed really cumbersome to do it that way, she missed getting her full dose of heparin while it was detached/paused, and I wondered afterwards if I was supposed to have a witness just to restart the heparin drip (it was paused, so I didn't have to re-enter anything, just push start). I also wondered if she should have had a peripheral line in addition to the PICC for IV push meds?

The second issue I've run into a few times is where I'm supposed to give a very small dose of an IV push med (usually Ativan) that, even when diluted, equals only 0.5 ml. How on earth do you reliably push that small of an amount over 2 minutes, especially since it's supposed to be in a 10 ml syringe (although I cheated and used a 3 ml syringe the last couple of times)? Besides pushing the plunger only a fraction of a millimeter every few seconds, it looks like most of the dose just sits in the saline lock and doesn't even get into the vein until it's flushed.

The other issue I am curious about is the compatibility of certain meds with NS. At both the hospital where I work as an LVN and the hospital where we have clinicals, I have never seen vials of D5W freely available to flush IV's with. Everyone just seems to use prefilled NS syringes no matter what the drug (as far as I've seen, anyways). IV Bactrim, for example, is only compatible with D5W according to my med book. Even so, I was told by my instructor that it still gets flushed with NS because the compatibility refers to what it is mixed in, not what it is flushed with. Is this correct, and how do nurses handle this in real life?

Then I also began to wonder, for the drugs that are only supposed to be mixed with certain solutions such as D5W, does it require a separate or Dr's order for that solution in order to be mixed? Or is it a "given" when the order is written (kind of like routine NS flushes for all saline locked pt's)?

Sorry to write a novel, but thanks for reading and I appreciate your input! :)

[turnforthenurse, MSN, NP]

The lumens of the PICC line have different exit openings. There is enough circulation going so that you may end up giving two meds through two different lumens that may be incompatible, but given through a PICC would be compatible because of the lumen exit openings.

I would have used the other port/lumen for other IV medications. I wouldn't have stopped the Heparin drip to give those IV medications. Heparin is a continuous infusion and you need to frequently monitor the heparin level/assay during therapy. Interruptions in therapy could change the assay level and then your drip may not be within therapeutic range anymore. Disconnecting and reconnecting the IV lines also increases the risk for infection.

[MunoRN, RN]

You don't need to stop the Heparin for 10 minutes and really not at all. Remember there's about 1.5 to 2 liters flowing by the ports of a PICC in the SVC every minute, that will "flush" meds from the area very quickly. Really, incompatibility is usually related to concentration and pH gradient, it usually doesn't take much dilution to create compatibility which is why you can have incompatible meds infusing simultaneously through two different ports even though those ports might be right next to each other.

As for 10ml syringes, they really aren't necessarily so long as you know the lumen is patent (follow your own P&P's of course). The larger surface area of 10ml sized syringe means the same amount of pressure applied at the plunger produces more PSI in the lumen. But so long as there isn't excessive back pressure in the lumen you won't be able to create significantly more pressure with a smaller syringe. The importance of exact dosing, infusion rate, and minimal accesses of different syringes and vials.

Both lumens can be used for meds, one is often designated for lab draws/CVP to avoid contamination, so consider what you're putting through the lumen. I would try and avoid drawing a ptt off a lumen infusing heparin regardless of how much you flush or waste, same for checking K through the line you infused the K in, but otherwise proper flushing and wasting should allow you to use a lumen designated for lab draws for pushes.