Bolus 25mL/hr

marienm, RN, CCRN · Sep 5, 2020

Not to muddy the waters but I will point out that if a bolus is running via gravity (with or without a pressure bag), Y-siting anything critical into it isn't a great idea because the critical drip can back up into the bolus tubing (path of least resistance if the patient bends their arm or whatever) and thus your flow rate of the drip will be inconsistent. Sure, the pump controlling the critical gtt is running at a consistent rate, but it doesn't know where the fluid is going. Imagine if 30mL of Levophed backed up into the bolus tubing due to a temporary occlusion and then all flowed in at once when the occlusion was removed...while the gtt isn't flowing in, you're tritrating it up because the BP is dropping, and then all of a sudden the BP spikes when flow is restored.

In addition to all the points made above, IV pump tubing tends to have check valves to prevent backflow, while bolus tubing does not. This might be part of why you've been told not to Y into a bolus.

JEE93, BSN, RN · Sep 7, 2020

I have a question, may have been answered already (not sure I'm kind of confused). New grad here...I have always wondered this. If you have two meds/fluids running at different rates, but giving through the same IV site, should you have the faster med/fluid connected directly to the IV with the slower med/fluid y-sited? I have always wondered if you hook the slower one up first, then y-site the faster one, the faster med/fluid won't actually be going at the fast rate, but instead will be slowed down by the slower med/fluid line. Is this right? Or am I just confused?

I have always thought it made sense to hook the faster med/fluid directly to the IV and y-site the slower meds/fluids, but during my practicum my preceptor did not do this and I even asked one time if we wanted one med hooked directly to the IV since it was running faster and the slower one y-sited and she told me no...?‍♂️. So, try to help me understand please!

I never know which one I should hook up first! Thanks!

Leah8183 · Sep 7, 2020

11 hours ago, JEE93 said:

I have a question, may have been answered already (not sure I'm kind of confused). New grad here...I have always wondered this. If you have two meds/fluids running at different rates, but giving through the same IV site, should you have the faster med/fluid connected directly to the IV with the slower med/fluid y-sited? I have always wondered if you hook the slower one up first, then y-site the faster one, the faster med/fluid won't actually be going at the fast rate, but instead will be slowed down by the slower med/fluid line. Is this right? Or am I just confused?

I have always thought it made sense to hook the faster med/fluid directly to the IV and y-site the slower meds/fluids, but during my practicum my preceptor did not do this and I even asked one time if we wanted one med hooked directly to the IV since it was running faster and the slower one y-sited and she told me no...?‍♂️. So, try to help me understand please!

I never know which one I should hook up first! Thanks!

I really hesitate to hook up anything that is going fast with something that is going at a prescribed rate because I don’t want to take the risk of punching something in fast, inadvertently. In my head, everything being mixed at the Y-site would be pushed in at the pump rate that is set at a faster rate. It’s going at a higher velocity than the one being pushed at a slower rate.

marienm, RN, CCRN · Sep 7, 2020

2 hours ago, Leah8183 said:

I really hesitate to hook up anything that is going fast with something that is going at a prescribed rate because I don’t want to take the risk of punching something in fast, inadvertently. In my head, everything being mixed at the Y-site would be pushed in at the pump rate that is set at a faster rate. It’s going at a higher velocity than the one being pushed at a slower rate.

JEE93: Short answer--connecting a faster fluid to the Y-side of a slower med will not slow the delivery of the faster fluid. After the pump, the only thing that slows the fluid down is the IV itself (size of lumen, patency of site). If you're running a fluid at 250mL/hour and a med at 50mL/hour and they are Y'd together, the IV is receiving 300mL/hour either way. I'm not sure if your preceptor meant "no, it doesn't matter" or "no, that's wrong," but it's worth asking her to clarify.

More thoughts for you both, though:

If all the fluids in question are controlled by individual pumps, it mostly doesn't matter once they are running. See the previous comments on this thread: Each pump is controlling the delivery of each fluid, and you won't get more med out of any pump by joining it with a faster flowing stream near the IV site. However, there are some things to think about:

Let's say you are running a pressor and it's the only piece of IV tubing connected to the patient. The provider orders a fluid bolus. You use a pump to control the bolus and you hook it up to the Y-site on the pressor. Very briefly, you will bolus the patient with 1-2 mL of the pressor as the bolus starts flowing in. How significant this is for your patient depends on their condition and the pressor in question. (If you're running at a low rate...only 2-4mL an hour...this bolus might be a big spike! Some meds, like Flolan, can never be bolused or interrupted and need their own tubing with no Y-sites connected directly to a dedicated lumen to prevent this.) For this reason, I personally prefer to run boluses on a separate lumen if at all possible. If that's not possible, I consider what med it is, how fast it's running, and which is "worse"--disconnecting the med and Y-ing it in above the new fluid vs. Y-ing the fluid into the med.

Another scenario to think about: Many critical care patients wind up with a lot of IV tubing connected to them via a combination of Y-sites and manifolds/stopcocks. Some of these might turn out to be only intermittently running. So let's say you set up a medication line for an antibiotic. And then you also get orders for midazolam which happens to be compatible with the abx. You connect the abx to the patient. When you start the midazolam, you Y-it in with the abx and titrate to the ordered level of sedation. Your abx takes 120 minutes to run and then you turn that pump off. The midazolam keeps running through the Y-site on the medication line and into the patient...no problem. But by the time you need to hang your next abx, the distal part of the medication line is full of midazolam. Starting the next dose of the abx boluses the patient with midazolam. Again, this might not be significant for your patient, but 1-2mL of 5mg/mL midazolam might be a lot! In this case, the problem happens because the tubing was left connected when not in use (even though the lumen was still being used). So, I prefer to connect intermittent meds to their own lumens and continuous gtts to different lumens. Follow your hospital policy about what to do with the lumens that are intermittently infusing (flush/disconnect/cap or use a KVO fluid to avoid breaking the connection.) If I can't do that, I connect intermittent meds to the main IV fluid line (if compatible) so that I know the main IV fluid will have flushed the line before I hang the next medication.

For most critical gtts, the key is really consistency of delivery. Usually you can see the result of the med (you're titrating a pressor to a minimum MAP, you're titrating sedation to a response, you're titrating lasix to a minimum urine output). Choose a configuration that allows the med to be delivered consistently, so your titration won't be muddled by inadvertent pauses or mini-boluses like I described above. For me, I find this usually takes the form of a "tree" where the main trunk is a continuously-running fluid. If I have more than 1-2 meds/gtts connected via the same lumen, I tend to use manifolds to connect each med or gtt into this main trunk, so I am confident that the main IV fluid has carried all of each med/gtt into the patient and don't need to worry about which Y-site might be pushing an extra bit of leftover med down the line.

Sorry, that's a lot! Does any of it help?

Leah8183 · Sep 7, 2020

Perfect explanation!

JEE93, BSN, RN · Sep 8, 2020

Thanks so much! That helped me a lot! I think over time with more practice and experience it will become easier and make more sense. It seems daunting to me right now as a new grad. Thanks for the explanation!