I'm a new nurse, and I have a couple questions about running secondary IV infusions:
When I hang a medication to be given via piggyback infusion, I usually use my IV pump to backprime the secondary tubing first, and then start the piggyback medication. This is the way I was taught. And it's also the way I was taught to back flush in between two different secondary medications. Anyway, I've noticed that some people also do this, but others prime the secondary tubing with the medication itself, then attach the secondary tubing to the secondary port on the pump cassette and start the pump. Thoughts?
The other part of my question has to do with VTBI. I always program my VTBI as exactly the amount that is in the secondary piggyback medication bag. But now I'm wondering, does the fact that I primed the secondary tubing with primary fluid mean that I'm not giving the patient the entire dose of medication? I assume that for the first few minutes of the secondary infusion, the patient is just receiving the fluid that was primed into the tubing. Even if I were to prime the secondary tubing with medication like some nurses do, the bottom half of the IV tubing that is common for the primary and secondary lines is filled with primary fluid and that's still what the patient is getting for the first few minutes. Not sure how much the tubing holds I will have to check the packaging but still. Do you see my confusion? So I'm wondering how you approach that.
If you're still with me.... I imagine there would be some residual in the secondary bag still. And the last part of my question goes off of that - I'm worried now that I might be always undermedicating my patients, because isn't there always residual secondary fluid? ie there is always some fluid left, if not in the minibag itself at least in the secondary line ie we don't run it dry. by this logic should we really be flushing the secondary line? but I've never heard of this...
One more thing. I see "overfill" listed on the label of some IV medications prepared by pharmacy. like the label will say 117 mL plus overfill. What do you program then? What's the rationale? How much overfill?? And therefore what do you set as the VTBI?
Not sure where to look for answers. Thanks for helping me think through this.
The overfill is in volume, not medication. A medication prepared in a 100ml bag with have overfill from two sources; the manufacturer overfills the fluid, typically about 5-10mls but it varies by the bag size and manufacturer, and then there will be the volume of the medication added (10ml of 500mg Ancef added to a 105ml bag for instance), but the overfill does not involve extra medication. A 500mg bag of Ancef will still only have 500mg of Ancef regardless of the overfill, so while it may have 120ml of fluid in it, it's still 500mg in the whole bag, which means the whole bag needs to be infused to give the ordered dose.
I get that but I also found sources that said that some manufacturers overfill with an extra 5-10 ml of fluid WITH medication in it. I think the moral of the story is check the bag carefully.
Priming the secondary tubing with the secondary medication instead of backpriming from the primary bag has the potential to waste the secondary medication resulting in underdosing, but also for subsequent secondary infusions this would result in the secondary tubing being manipulated for no reason, once the secondary tubing is attached it should be considered permanently attached, flushing the line between medications can be done by backflushing (hold the empty bag from the previous secondary infusion below the level of the primary bag, this will flush primary fluid through the tubing and into the old secondary bag, flush sufficiently to prepare the tubing for the next med, then toss the previous bag). The same technique can be used for first dose to prime the secondary tubing using the primary fluid.
I've used Sigmas at the last two places I've worked.
I know how to backflush. Not a newbie. Still not convinced that it's best practice however I'm not trying to argue with you. Again, I think there are some fundamental differences in how our facilities do things and I am bound to follow the policies of mine.
I get that but I also found sources that said that some manufacturers overfill with an extra 5-10 ml of fluid WITH medication in it. I think the moral of the story is check the bag carefully.
This came up as a question when a facility I worked at was re-doing our IV infusion policies. The answer we got back from our pharmacy director who reportedly spoke with a couple of manufacturers was that they can only overfill volume, they can't put more medication in the bag than what is stated on the bag otherwise they face FDA fines.
Priming the secondary tubing with the secondary medication instead of backpriming from the primary bag has the potential to waste the secondary medication resulting in underdosing, but also for subsequent secondary infusions this would result in the secondary tubing being manipulated for no reason, once the secondary tubing is attached it should be considered permanently attached, flushing the line between medications can be done by backflushing (hold the empty bag from the previous secondary infusion below the level of the primary bag, this will flush primary fluid through the tubing and into the old secondary bag, flush sufficiently to prepare the tubing for the next med, then toss the previous bag). The same technique can be used for first dose to prime the secondary tubing using the primary fluid.
I've used Sigmas at the last two places I've worked.
It seems to me that either way should be fine, whether you prime with secondary (taking care to not let fluid drip out before securing it in the y-port of the primary) or back prime.
We should know our facilities policy. Mine is to prime using the secondary.
The goal either way is to minimize line entry, doing nothing more than spiking the new secondary med bag if at all possible.
I don't see a logical reason to back prime the secondary line with primary fluid unless it is for compatibility purposes when the secondary line is used for more than one med.
The quote below is from our hospital P&P (we use Lippincott)
I need to investigate a little further, because our unit does not do the programmed bolus at the end as it is written...
I find it interesting that there is so much variation in such a simple procedure. The inconsistency in administration leads to patients sometimes receiving significantly more or less than what is ordered.
Unless they aren't to receive the full dose of the bag then they won't be getting more than ordered, one of the main purposes of a primary/secondary setup is to avoid giving less than the ordered amount. The main purpose of backpriming rather than unnecessarily disconnecting the secondary to prime from the secondary bag is that connection manipulations are a known risk for introducing bacteria.
When we were reviewing our IV policy the question came up frequently as to what the purpose of backflushing and backpriming was, so we audited each technique. When priming a line, some nurses wasted as little as
I agree those advantages should be weighed against the advantages of not backflushing and backpriming, but I'm still not clear what those advantages are.
It seems to me that either way should be fine, whether you prime with secondary (taking care to not let fluid drip out before securing it in the y-port of the primary) or back prime.
We should know our facilities policy. Mine is to prime using the secondary.
The goal either way is to minimize line entry, doing nothing more than spiking the new secondary med bag if at all possible.
Since the secondary drip chamber and a portion of the tubing will generally be empty after the infusion, how are you priming the secondary line without backpriming and also without disconnecting the secondary tubing in order to "minimize line entry"?
This came up as a question when a facility I worked at was re-doing our IV infusion policies. The answer we got back from our pharmacy director who reportedly spoke with a couple of manufacturers was that they can only overfill volume, they can't put more medication in the bag than what is stated on the bag otherwise they face FDA fines.
Please refer to the link I posted. The NIH article clearly states that some manufacturers indeed put more medication in the bag. The bag label lists the concentration of the drug not the total amount of drug in the bag because the volume may vary. The example they used was Gentamicin. Again, the take away from this isn't who's way is the "right" way but instead that we need to be vigilant in reading the labels to make sure we aren't under or over dosing our patients by our practice.
Please refer to the link I posted. The NIH article clearly states that some manufacturers indeed put more medication in the bag. The bag label lists the concentration of the drug not the total amount of drug in the bag because the volume may vary. The example they used was Gentamicin. Again, the take away from this isn't who's way is the "right" way but instead that we need to be vigilant in reading the labels to make sure we aren't under or over dosing our patients by our practice.
I did read the link but it doesn't say that manufacturers put more medication in their pre-mixed bags, it said that the IV fluid bags (prior to medication being added) typically have more volume than what the bag says, so when x amount of medication is added, it is more dilute than expected if the extra volume wasn't considered, the other example in the article is when a medication is mixed on-site and the volume of the admixture is not considered in the final concentration: A 100 ml bag that actually has 105ml in it, 20ml of antibiotic is added, this gives you a final concentration of x mg of drug in 125ml, but these are sometimes mislabeled as x mg of drug in 100ml.
For an antibiotic where the full added dose is to be given, then the entire bag should be infused, regardless of the final volume.
I did read the link but it doesn't say that manufacturers put more medication in their pre-mixed bags, it said that the IV fluid bags (prior to medication being added) typically have more volume than what the bag says, so when x amount of medication is added, it is more dilute than expected if the extra volume wasn't considered, the other example in the article is when a medication is mixed on-site and the volume of the admixture is not considered in the final concentration: A 100 ml bag that actually has 105ml in it, 20ml of antibiotic is added, this gives you a final concentration of x mg of drug in 125ml, but these are sometimes mislabeled as x mg of drug in 100ml.
For an antibiotic where the full added dose is to be given, then the entire bag should be infused, regardless of the final volume.
You must have missed this part.
"With this method, the medication concentration in the container (drug per unit volume) at the time of manufacture is the same as the concentration on the label. However, the final product contains more volume than the label indicates due to overfill. For example, an IV bag of gentamicin labeled as containing 80 mg/100 mL contains the labeled 80 mg and another 4 mg of the drug in the 5 mL of overfill."
"With this method, the medication concentration in the container (drug per unit volume) at the time of manufacture is the same as the concentration on the label. However, the final product contains more volume than the label indicates due to overfill. For example, an IV bag of gentamicin labeled as containing 80 mg/100 mL contains the labeled 80 mg and another 4 mg of the drug in the 5 mL of overfill."
Manufacturers do figure in for remaining secondary tubing volume, they do not figure in for priming volume or remaining drug in the bag.
Manufacturers do figure in for remaining secondary tubing volume, they do not figure in for priming volume or remaining drug in the bag.
No. They overfill to accommodate for evaporation. Regardless, you firmly stated that manufacturers only add volume never additional drug and went on to say it was an FDA violation. The NIH disagrees. And again, this isn't about being right. It's about being vigilant. I'm not clear on how your above quoted post is even remotely related to what I posted.
Wuzzie
5,238 Posts
I get that but I also found sources that said that some manufacturers overfill with an extra 5-10 ml of fluid WITH medication in it. I think the moral of the story is check the bag carefully.