Ok, something came up today that got me to wondering... is there a rationale for using a smaller angiocath than possible when starting an IV on a patient?
I mean, back in my Paramedic days, we didn't start anything smaller than a 16 antecubital and tried really hard to get an 18 in even for hands if we at all could, because we had no clue what kind of fluids the patient would end up needing, and I was taught that blood products needed at least an 18. Ok, so I've since been educated that blood products *can* use a 20, but an 18 is preferable. And I'm not calling for 14 and 16 in regular use.
But.
Last night the nurse knew my pt needed a unit of PBRC and it would be coming on my shift. The existing IV (an 18) she said was leaking, so she put a 20 in so I'd have it for the PBRC. As a new nurse, I asked around (supervisor, other ICU nurse on duty) and the consensus was that if I could get an 18 in, that would be preferable. Pt had decent veins and I had no trouble starting an 18. (I'm in an LTAC ICU)
So, it got me to thinking... the only nurses I have seen routinely use 18's are ICU and ER/Trauma nurses. Everyone else seems married to 20's and 22's. Is there a rationale for using less than an 18 if you can get an 18 in and assuming there's no expectation of administering blood? (I fully recognize there are lots of patients that you're lucky to get a 22 in, and those aren't the ones I'm talking about.) Or is it that the larger angiocaths scare a lot of nurses for some reason?
I've tried to search my references and even Google for it, and haven't found much of any help. All I've really found is that 20 is the minimum for blood, and 18 is preferred.
Actually, I'm an ICU nurse, and usually, I'm "married" to the 20 gauge and everyone else seems to be on my unit, too. Usually because that's the largest catheter I or anyone else can insert in most of the patients (not the best veins), but on those rare occasions with the good pipes for veins, I'll use an 18 gauge. I always use the largest possible IV catheter for the reasons you mentioned since our patients are likely to require PRBC's or even large amount of volume/fluids at some point. If it's a stable patient who seems like they'll be leaving soon, then I use a 20, no reason to stick them with a larger needle lol.
Also consider that to draw blood from a patient without lysing, they use 23 or 25 gauge butterfly needles for phlebotomy. I am also married to the 20g IVs.
I agree with the irritation to the veins in larger bore IVs. I'm looking for (but haven't found it yet) an article I had seen recently about using smaller needles instead of the larger ones for that reason.
I agree that nurses outside of critical care areas seem "married" to 20s & 22s. It's culture, not rationale.
Actually, doesn't the infusion nurses society advocate the smallest cath to prevent phlebitis? That's what I was taught in my hospital's IV class (along with avoiding ACs and other joints for longer IV life). Working in an ER, we have different priorities so that advice got ignored, but now that I work on a floor, if a 22 does the job, causes less irritation to the vein, I don't try to be an IV hero.
I start a ton of IV's as a rapid response nurse. I have to say I will go with a 20g preferably, but if not I will put in a 22g if needed. I typically use a 20 g unless asked by a physician to start a larger gauge. Last week I was asked to start a 18 g in a pt and had to to tell the MD that a 20 g was the best I could get.
The infusion society does recommend the smallest, shortest IV for less irritation.
I work in a GI lab, and if we even have 18's, I have never seen one. Maybe in the crash cart.
We use 20's and 22's usually, or even a 24 if that's all we can get. We are not going to send a patient home who has done a bowel prep the day before without doing their procedure just because we can't get a larger bore IV. We use whatever we can get. It's only in them for a couple of hours max.
I work in a critical care unit that stocks 22, 20, and 18s on our supply cart. We do have 16s and 14s on our crash cart but I've never seen them used. I use several criteria in my selection. I look at the size and condition of veins (and arms). What do I think I can reasonably get? What are they in for and what do I anticipate them requiring as far as IVs are concerned. I usually go middle of the road with a 20, smaller with a 22 if they have difficult veins, and try for an 18 if they have been or may be a code.
Specializes in burn ICU, SICU, ER, Trauma Rapid Response.
Smaller is better for most things other than fluid resuscitation. Smaller is definiatly better for giving meds like ABX but even more important when giving vesicants.
What you want is as much blood flowing around the catheter as possible. Lage IVs in smaller veins means that little or no blood flows around the catheter. That means that whatever you are infusing is alone in the vein and not diluted by blood, or not diluted much.
Nearly all inpatients should have 22ga IVs unless there is reason to think that fluid resuscitation will be needed (GI bleed for example) or they are going to get blood. In the case of blood a 20ga is fine, though of course blood can be given through 22 and 24 ga IVs
Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
Actually, doesn't the infusion nurses society advocate the smallest cath to prevent phlebitis? That's what I was taught in my hospital's IV class (along with avoiding ACs and other joints for longer IV life). Working in an ER, we have different priorities so that advice got ignored, but now that I work on a floor, if a 22 does the job, causes less irritation to the vein, I don't try to be an IV hero.
Yes they do......the standard is to place the smallest catheter needed for the task at hand. Less trauma to the vein less chance for phlebitis/complications. Yes medics and the ER are married to their large bore IV"s but these are for resuscitative purposes and not meant for long term
I also learned that the smallest gauge IV needed to accomplish the job is the way you want to go, not the largest. My hospital's policy for transfusing blood is to use a 22g in adults. The only reason I would put a 20g in a pt is if they need a CT scan and CT calls and says hey, we need a 20g. As for vesicants, I dont think it's the gauge that matters but the site and the speed of the infusion. You dont want to put vesicants in people's hands.
Plus we have to place IVs of the appropriate size in the appropriate location for CTAs. The standard that I have heard is a 20 (or larger) "above the wrist" and it has to be an 18 if the pt is over a certain weight. Although this does vary by CT tech...some are willing to do a CT with a 22 or with and IV "in" the wrist. On the other hand, I had a CT tech insist that it had to be an 18 ga in the right AC. When the pt came over with one in the left AC, the tech would not do the scan.
Good Morning, Gil
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Actually, I'm an ICU nurse, and usually, I'm "married" to the 20 gauge and everyone else seems to be on my unit, too. Usually because that's the largest catheter I or anyone else can insert in most of the patients (not the best veins), but on those rare occasions with the good pipes for veins, I'll use an 18 gauge. I always use the largest possible IV catheter for the reasons you mentioned since our patients are likely to require PRBC's or even large amount of volume/fluids at some point. If it's a stable patient who seems like they'll be leaving soon, then I use a 20, no reason to stick them with a larger needle lol.