Back priming vs back flushing??

[amw79]

Hi ya'll. New grad here, prepping for the NCLEX. I have a general question regarding back priming. I understand how its done and know the purpose (to avoid losing medication and keep a closed system). I am a bit stumped on one aspect if someone can please clear it up.....if I am switching out a secondary IVAB for instance....what is acceptable and/or best practice...can I simple spike the new IVAB and if the tubing is good, backprime it and start the infusion? Or do I have to backprime/flush with the OLD BAG before spiking the new secondary. If it is the SAME medicine and it is a closed system I do not see why it would matter either way....while I see it may be best to flush into the old bag to clean out all the old med, etc. is it acceptable to do it either way? Am I right in understanding back-FLUSHING with the old bag is most appropriate when using another compatible secondary med? My instructor says to just use new tubing for all different antibiotics, but I know this may not be policy at every hospital. Please give me some guidance, thanks!

-A.W

[MunoRN, RN]

I can't make any promises, but I really doubt that particular question would appear on the NCLEX. The questions are more aimed at how you apply your knowledge and the thought processes involved.

But to answer your question, your instructor is incorrect in saying you should use a different secondary tubing for different antibiotics, that is arguably bad practice, although a disturbingly common bad practice. One of the most challenging errors to fix in antibiotic administration is the problem of the secondary being clamped and the patient missing a dose, if it weren't for changing the secondary tubing for each antibiotic then there would be no need to ever clamp it. The other issue is that your unnecessarily breaking a closed system, which increases the risk of contamination and resulting infection. Those are two major ways in which changing the secondary tubing for each antibiotic potentially harms the patient, yet there are no advantages or benefits to this practice.

As for when to backflush/prime, we are creatures of habit, so for that reason I think it makes sense to always backflush into the old bag prior to hanging the next dose since this works for both compatible and incompatible antibiotics, that way the consistent habit that develops works in all situations.

[iluvivt, BSN, RN]

First you need to understand that any secondary hung MUST be compatible with the primary IVF. The secondaries need not be compatible with each other and this the point of backpriming. So if you are are going to hang a dose of Cefazolin and the last secondary given was Cefazolin then there is no need to bsckprime. Now if you are going to administer a different agent that is not compatible with the last secondary hung that yes you need to backprime. You need to backprime into the mini bag a few times BEFORE you hang the next incompatible medication or agent.

[amw79]

Thank you for your input! That was greatly helpful:)

[iluvivt, BSN, RN]

As far as hanging a new secondary tubing for different agents...yes you can do this but there are a few cons to doing it this way. First you are having additional breaks into the system...second you are increasing the expense. ..third INS states that secondaries that are connected and disconnected in this matter should be treated as primary intermittent tubing and a hold be have a max hang time of 24 hrs....DC does not specifically address the topic... Personally if done correctly backpriming is so much easier, saves time and resources and I love the idea of minimizing the entries into the IV system decreasing the risk of extrinsic contamination

[amw79]

Thanks ilivivt. I understand what you are saying regarding compatible vs noncompatible meds...however I'm under the impression that back priming is ALWAYS necessary in order to clear any air out of the line once its run dry....now I'm referring to the secondary running dry...of course with the primary this may not be necessary since its often switched out before it runs dry...am I correct?

[amw79]

good points!

[MunoRN, RN]

Thanks ilivivt. I understand what you are saying regarding compatible vs noncompatible meds...however I'm under the impression that back priming is ALWAYS necessary in order to clear any air out of the line once its run dry....now I'm referring to the secondary running dry...of course with the primary this may not be necessary since its often switched out before it runs dry...am I correct?

The fluid level in the secondary set and bag will go down to the level of the fluid in the primary bag, so since when properly set up you will usually end up with some air in the secondary set when an infusion is done, requiring backpriming up to the level of the drip chamber when preparing the next dose. The goal with the primary line is to change bags before the drip chamber or line runs dry, so ideally that's not a problem, although it certainly does happen.

[iluvivt, BSN, RN]

Yes MunoRN explained that well and is correct. If you can set your secondary volume on your pump to the exact amount that needs to be delivered so it does not empty the drip chamber or at least get to the level of the primary and you are giving the same medication for the next secondary you will not have any air in the line. If you are using a gravity set you would have to watch it and prevent the drip chamber from running dry. It may sound confusing but it is really not. If you do have a bit of air in the secondary line you would need to backprime it to eliminate it if your goal is to keep that secondary attached at all times. Keep in mind in this case the backprime would just be to clear the line of air. You will be tortured with an air alarm if you do not and generally it is not considered good practice to leave large amounts of air in IV tubing...more critical in pediatrics. Some nurses just disconnect the secondary..prime it and reattach but this again is not the best practice since your are disconnecting it which increases the risk for infection. Does that explain it?

[amw79]

yes thanks!