Appropriate use of smaller gauge IV's

[MarySunshine]

I'm a new grad and have only started on IV in my whole life, so this is the voice of inexperience speaking here. :) However, I did attend an IV class in which the instructor said that w/ caustic IV meds the best thing you can do is use the smallest gauge in the largest vein you can find. She also said that there is no reason you cannot use a 22 gauge for blood tranfusions. You just may have to flush it if it begins to slow down.

However, I am orienting in an ICU where they try to get large gauge catheters in people, despite the fact that we infuse things such as mannitol, dilantin, and potassium peripherally. I also suggested to a preceptor that we should use a smaller gauge on a difficult stick pt. who needed a tranfusion and she said that you can't do that -- the cells would lyse. I'm not really up for arguing with my preceptors at this point in my career.

I do understand that certain hemodynamic emergencies may require very fast fluid infusion, so a large gauge is needed, but wouldn't it be better practice to use smaller gauges (even 24's) when possible? A stable pt. receiving caustic IV meds should be safe with 2 PIV's that are small gauge, right (or maybe a small gauge for meds and a large gauge for fluids)? I'd like to incorporate this theory into my practice if it is sound. Thanks :)

P.S. I've noticed a lot of eye rolling and sighing for nurses when we get transports with the 22's and 24's. Does anyone know of any good clinical references for this? I'm confused about who is right and I want the best for the patients.

[fergus51]

I used to work L&D and we would try to get 18g in everyone in case we needed to give blood or large volumes of fluid. Hospital policy was that blood could only be given through 18g or larger, again because of the belief that the blood cells would lyse. Now, I work NICU and we obviously can't use 18g! We use 24 g on our babies and give blood through it all the time, so I don't buy the lysis argument anymore. The only thing is you probably wouldn't be able to give the blood as fast. I'm sorry I don't have any references for you, but I want to commend you for looking. It's great to see new nurses trying to incorporate evidence based practice into their work.

[pricklypear]

Most common size we use are 20g. We will often use 22g in difficult sticks, no big deal - never had a problem with either one. We don't routinely put 18g in our ICU, but EMS and surgery use them a lot. I've infused blood often through a 20, but I'm not sure if I have in a 22. If that was all I had, though, I'd sure give it a try - but very slowly. Blood certainly does not HAVE to be given only through an 18g needle.

Check your hospital's policy, and make sure there are no reasons not to use 20s or 22s on the patients. If not, don't worry about what everybody else is doing, you can start smaller gauge ivs on your own pts if you want!

BTW, I've heard lots of people say that 18g are actually eaiser to start than smaller gauges.

[suzanne4, RN]

I do not agree with your instructor's thoughts.

The larger the bore of the IV, the easier it will be to keep the vein from collapsing.

Best suggestion is to do what I do when I teach an IV class to nursing students: get hold of a 24G, 22G, 20G, 18G. Open them up and compare the difference in the quality and thickness of the catheters. You will find that the 24G will kink very rapidly, they are extremely soft and pliable, best for infants. The 22G can still kink, but it much sturdier than the 24G. The 20G is what you will see on average most of the time. 18G should be used for surgical patients in almost all cases, where there is any possibility that they will require fluids rapidly or blood.

Unfortunately, in the past, I have received patients into the OR with a 22G or a 24G on a patient with a suspected ruptured ectopic pregnancy from the ER. Make sure that the catheter that is placed is appropriate for what the anticipated needs of your patient are.

In an adult patient, best IV size for blood is the 18G, a 20G can be used, but is not preferred.

Hope that this helps. :wink2: By the way, if the drug is considered caustic, the most important thing is to make sure that catheter actualy stays in the vein and doesn't infiltrate to surrounding tissue, not the size of the catheter.

[Tweety, BSN, RN]

There's so many opinions no wonder you're confused. So here's mine. :)

The standard is to use the smallest IV to get the job done. Larger sizes cause greater risk for infection and infiltration. I don't have documentation but the IV Nurses Association might be a place to look.

Critical care nurses, ER nurses, and perhaps L&D nurses rarely use anything less than a 20g for anything. So you're apt to get a wide variety of opinions. (Some even throw their noses up at 22 g's thinking it a sign of a poor IV nurse who uses them.)

I do agree that for blood 20 g or higher is best. But 22 g is acceptable in cases where IV access is difficult.

I agree that for the vesicants, it's not the size of the needle that matters, but is it in the vein? is the question to ask. What's the smallest IV I can use to get the job done?

24 guages on adults don't last long because they are too short in my opinion and I only use them when desparate, but use 22 g commonly in my practice in med-surg.

Good luck.

[Allyson, RN]

I know this is an old post but I'd like to comment also. ER/ICU nursing hx. Medics try for 18G. A 20G or larger IV is the size of choice. CT IV contrast injects at speeds that require 20G non-hand veins or larger.

22G and 24G IVs frequently kink and/or clot more often - requiring early restarts. The flexibility of this size also makes for a more difficult start. It also takes a considerably longer time for IVF to drip through these sizes. I have not noticed a difference in pain compared to when I start a 20G over the smaller sizes - its all in the technique.

In our ICU central lines are the lines of choice because they empty into larger vessels that won't be irritated by pressors or irritating antibiotics such as Vanco. The gauge of the IV makes no difference (its the size of the vein).

As for blood administration, you give it through what you've got - peds get it through 24G. Needles

In our ER, if you're concerned about fluid/blood recessitation you place the largest size you can; neverthless, 24G are sometimes the only size you can place.

Get in the habit of only bringing in a 20G with you to start your IV - If you bring a smaller size you'll psych yourself out and use it. Also, avoid hand veins altogether d/t increased frequency of phlebitis and discomfort. Our hospital also asks that we avoid starts in the AC if possible.

[Zookeeper3]

I even use 20G when using thumbs and fingers if they are the last resort.

[OCNRN63, RN]

We have patients who have lousy veins and get their transfusions with 24g. It's never an issue, and we don't have to run the blood more slowly.

[iluvivt, BSN, RN]

Your instructor was correct that is the INS standard....use the shortest smallest catheter that will meet your needs. Thats the kicker..."that will meet your needs." I find the 24s not very helpful in adults but I will use them when I have to. Yes.... you can give blood through a 22 gauge..but it works best if it is fairly new or I find they tend to leak if they have been in for awhile....If you can place at least a 20 gauge for blood that is better due to its viscosity. So assess the whole situation..what you need to administer..the Ph and osmolarity....the quality of the patient's veins....their available veins...the pts overall condition.....how many sites do you need. If I have looked and looked and I can only fins a vein or 2 to attempt....I may not always push for a larger gauge..I will get the 22 in..and make sure it is good. You can save a life with a 22 gauge..yrs ago i started a 22 gauge on this man...several hrs later he coded.....it was late about 1130 pm..no one could get anything else in..not even me initially....we saved his life with that 22 gauge...once we got some fluids in him I was able to get another IV in him