Large Bore IVs and Rapid Infusion

[VFlutter]

I have had a few days off and got bored so I figured I would write this up. I've had this conversation a few times lately and think that is useful knowledge. Just a few tips and tricks. There is very much an art along with the science of Rapid Infusion and Large Bore IVs.

For the sake of this discussion Large Bore refers to 14-16g IVs. Always consider what is going on with your patient; For those who truly need large volumes of fluid infused rapidly it can be a lifesaver however if done inappropriately it can very detrimental. Remember balanced resuscitation, permissive hypotension, hyperchloremic acidosis, and all that fun stuff.

IV selection is extremely important when using rapid transfusion devices such as a Level One or Bellmont however is still important for EMS. A 14g with a pressure bag can infuse 1L of fluid is under 2 minutes. Also great for blood products. Depending on length some 14g catheters actually flow faster than a Cordis.

/https://lifeinthefastlane.com/ccc/device-flow-rates/

https://etmcourse.com/large-bore-iv-access-showdown/

For large volume rapid infusion short/wide PIV catheters are best. As you can see from the chart length makes a big difference in IVs of the same gauge (Poiseuille's Law). IOs and CVC are great for medications but worthless for rapid infusion. Pressure bags or just squeezing the bag can increase flow rates substantially.

The biggest thing that many people do not realize is how much flow rates are decreased with needless connectors or extension sets. As much as 30-40% less. If you need high flow connect tubing directly to the catheter hub. It is hard to break the habit of instantly putting a saline lock and the IV you just placed.

If you only have the one IV and you are frequently pushing medications then a 3-way stopcock is a good compromise. Stopcocks will restrict flow slightly but much less than a needless connector. If you happen to see a stopcock with a yellow top then those are usually "High Flow" are will likely flow as fast as your IV will allow.

You can usually find these in the Cath Lab or with Anesthesia supplies.

So long story short Large Bore IVs are extremely useful when used appropriately. If you need high flow then go for a 14g or 16g, ditch the needless connector, and grab a pressure bag.

 

[VFlutter]

IO flow rates for comparison.

 

[Summit]

You either have a sternal IO or your don't.

I hated sternal IOs in hospital because they were rarely successful first attempt (or rather failed to stay patent). I think it had to do with patients being in a bed rather than on the ground.

We switched to EZIO

 

[VFlutter]

You either have a sternal IO or your don't.

I hated sternal IOs in hospital because they were rarely successful first attempt (or rather failed to stay patent). I think it had to do with patients being in a bed rather than on the ground.

We switched to EZIO

Ya the increased flow rated of Sternal IOs are still not worth the hassle and practical limitations because IMO you shouldn't be relying on IOs for fluid resuscitation anyway.

 

[MSDeltaFlt]

Just don't lose the sternal IO removal tool.

 

[NomadicMedic]

Just don't lose the sternal IO removal tool.

 

[Brandon O]

Does anyone have experience with those RICs? I have a hard time imagining cramming something that size into a peripheral vein.

 

[Carlos Danger]

Does anyone have experience with those RICs? I have a hard time imagining cramming something that size into a peripheral vein.

I’ve placed them a handful of times. I like them. You do need a larger vein than the instructions suggest but they are pretty slick.

 

[Peak]

Does anyone have experience with those RICs? I have a hard time imagining cramming something that size into a peripheral vein.

They are inserted using seldinger technique so while you still need a vein that is large enough to accommodate the RIC they are much easier than inserting an angio over needle device of similar size.

 

[Brandon O]

They are inserted using seldinger technique so while you still need a vein that is large enough to accommodate the RIC they are much easier than inserting an angio over needle device of similar size.

Yeah. But you can't squeeze a pot roast into a keyhole even if you use a funnel. Veins don't dilate and fitting an 8.5fr catheter into most of the upper extremity veins I've seen under ultrasound would be pretty questionable.

I'd worry about destroying the vein. Is there data on the success rate of the "RIC step," versus loss of the line?

 

[Peak]

Yeah. But you can't squeeze a pot roast into a keyhole even if you use a funnel. Veins don't dilate and fitting an 8.5fr catheter into most of the upper extremity veins I've seen under ultrasound would be pretty questionable.

I'd worry about destroying the vein. Is there data on the success rate of the "RIC step," versus loss of the line?

I'm not sure about success rates but a 8.5 RIC is going to have an ID of about 2.8 mm and an OD somewhere around 3.2ish mm. You'd be surprised how large of a line a vein can take, I've put peripheral 20s in 1 year olds and 18s in 4 year olds with ultrasound. I would say that the majority of large kids and adults could easily take a 8.5 french line in their brachial or basilic veins, and most of the remaining small adults or school age kids could take a 7 French line. If you consider placement in the IJ or femoral then there really aren't many patients who are not candidates.

 

[Brandon O]

Hm. Maybe I'm overestimating the size. I'm just mentally comparing to a big Cordis and have a hard time imagining one of those in an arm. (Although yes, I have seen it.)

I suppose veins are distensible. Do you do the dilation with a tourniquet on?

 

[VFlutter]

I totally agree most people would easily tolerate a 8.5fr RIC in an upper arm vein under US. Basilic veins seem perfect for it. However I would be a little hesitant in a palpable superficial vein unless they were like a bodybuilder with massive veins. Most ACs are probably good to go tho.

Except the relatively short length probably precludes placement in anything too deep.

 

[Carlos Danger]

So like I said, I think the RIC is a cool device, but its best use is probably limited to replacing an existing 20g. In that case you could run into some difficulty getting the dilator in far enough to fit the catheter, depending on the size of the vein. There are plenty of places a 20g will fit that a RIC won't.

If you are having to start from scratch, it is probably easier in most cases to just place a 14g or 16g using US.

 

[Peak]

I suppose veins are distensible. Do you do the dilation with a tourniquet on?

You can but I wouldn't, once you have the 20 in or advanced the wire if you use a needle you can release the tourniquet. When you insert a PICC you leave the tourniquet on to remain sterile since you typically don't have someone with you, so you certainly can but would be increasing the chance of blowing the vein.