Radial A line difficulty

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heathermed

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hello everyone...

I was hoping to get some advice.

I'm having a little trouble with radial A lines. I consistently manage to hit the artery and get flash. Unfortunately, when I advance the wire and then the catheter, I lose it.

I'm not sure what I'm doing wrong but this has happened on numerous occasions. I get flash, I advance the wire... catheter goes in... wire comes out... NO FLOW.

Any suggestions?
any general tips on A line placement would also be helpful...

thanks in advance!

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Jet had a good thread on a line recovery when the wire won't thread, see if you can find it. Basically, wire won't thread, pull wire back, and use through and through technique.

The technique that has served me well is get the flash at a your 45* angle then drop the angle to about 20* and advance the needle about 1-2mm, when you actually feel the catheter go into the lumen, then thread your wire and advance catheter.
 
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If the wire starts to feel even slightly "crunchy" as you advance it then the wire isn't in the vessel.
 
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If the wire starts to feel even slightly "crunchy" as you advance it then the wire isn't in the vessel.

best advice. if the wire wont advance perfectly smoothly, dont try and force the catheter, pull back or advance slightly, change your angle, try something else.
 
Do 75-100. I posted the same thing when I was a resident. One way I practiced is I went to office max bought a neioprene covers for my ipad and took the string on my laniard and would practice sticking the string underneath the neoprene binder.
 
]Jet had a good thread on a line recovery when the wire won't thread, see if you can find it. Basically, wire won't thread, pull wire back, and use through and through technique.[/B]

This is a VERY USEFUL skill to learn.

I'd say 50% of the time I get a flash, attempt to thread wire, wire meets resistance...

HERE'S WHERE PEOPLE F U CK UP... even though resistance is felt, they thread it (to nowhere lol) anyway, then advance the catheter to nowhere.

Some A lines, you thread the wire and it's SOOOO smooth...no resistance...like a

knife cutting thru a rare Ruth's Chris Steakhouse ribeye...


Others, not so much...you attempt to thread the wire and

RESISTANCE IS FELT....

here's the trick that'll make you a ROKKSTARR at A-lines

If resistance is felt, back out the wire and push thru the artery.

The RESCUE technique I've described (after you've pushed thru the artery) in the post Scudrunner mentioned

almost never fails.
 
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I go through and through from the get go. Separate angiocath and wire.

2 years ago I slowly switched from a .025g wire to a .021g wire.

.021g wire can sneak past plaque/resistance and guide your angiocath where it needs to go.
I also like the biofeedback I get from holding the wire itself.
 
The technique that has served me well is get the flash at a your 45* angle then drop the angle to about 20* and advance about 1-2mm, when you actually feel the catheter go into the lumen, then thread your wire and advance catheter.

Wrong. I assume you are using the arrow kit that comes with a wire. Advancing the catheter AFTER the flash but BEFORE you thread the wire is the way to back wall the artery and/or lose the line. Wire goes through the same hole that the flash of blood comes in. 95% of time you should be able to advance the wire after a flash without advancing the needle. Once the wire is hubbed, you can do whatever you want, drop your angle, advance the whole kit, or just push off the catheter. Knowing when not to tread the wire comes with experience. I only go through and through if I think I back walled and try to save the line.
 
95% of time you should be able to advance the wire after a flash without advancing the needle. Once the wire is hubbed, you can do whatever you want, drop your angle, advance the whole kit, or just push off the catheter. Knowing when not to tread the wire comes with experience. I only go through and through if I think I back walled and try to save the line.

:laugh::laugh::laugh:

I wish your 95% of the time quote was true!

That's a PIPE DREAM man.

Hence why I invented a way to save an A line, since about

50% of the time

the wire meets resistance.
 
Hence why I invented a way to save an A line.

Thanks for inventing the through-and-through method :)

If you are having trouble threading the wire 50% of the time, you are doing something wrong. My guess is your initial angle is steeper than mine. Arrow kit works well if used correctly. If you are making two holes in the artery every other time, then just use the regular angiocath. I may have exaggerated about the 95% rate, but I only do old, sick hearts usually after someone else had a first shot and still no where near the 50% failure rate.

I like these discussion because I got to learn different ways of doing the same procedure. Classic through and through, bloodless syringe on angiocath, arrow kits, bevel down... residents should try all of them. But when something works for someone but not you, you should reflect on what it is that you are doing differently.
 
I go through and through 100% of the time for the exact reason your talking about. Once you see pulsitile flow you can advance the wire with confidence then the catheter.
 
One of my colleagues showed me Jet's rescue technique. Doesn't work for her, nor did it work for me. I suspect that the issue is that vasospasm has already been induced.

What works best for me is to simply remove the needle when I am sure that, despite lack of a flash, I am in the vessel. I have seen this work time and again.
 
I'm having a little trouble with radial A lines. I consistently manage to hit the artery and get flash. Unfortunately, when I advance the wire and then the catheter, I lose it.

I'm not sure what I'm doing wrong but this has happened on numerous occasions. I get flash, I advance the wire... catheter goes in... wire comes out... NO FLOW.

Any suggestions?
any general tips on A line placement would also be helpful...

is it a little flash or a good flash you're getting? if the patient is hypotensive a little flash may be all you get, but for most normotensive pts, you should see a good flash at least a couple of centimeters into the tube, otherwise that aint it.

i see some people insert the aline near the wrist crease. i tend to go a little more proximal - maybe cm or more from the crease of the wrist. the artery is a little deeper there but also a little larger so the catheter threads better i think. also, i think some people go in at way too steep an angle. i dont know if it's right or wrong and it doesnt matter if the aline goes in fine, but i enter the skin at about 30 degrees angle.

like all procedures, alines are just something you have to do a lot of and develop "a feel" for. when i thread my catheter over the guidewire, i KNOW 99.3% of the time whether it's in the artery or not before i pull the wire out.
 
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Wrong. I assume you are using the arrow kit that comes with a wire. Advancing the catheter AFTER the flash but BEFORE you thread the wire is the way to back wall the artery and/or lose the line. Wire goes through the same hole that the flash of blood comes in. 95% of time you should be able to advance the wire after a flash without advancing the needle. Once the wire is hubbed, you can do whatever you want, drop your angle, advance the whole kit, or just push off the catheter. Knowing when not to tread the wire comes with experience. I only go through and through if I think I back walled and try to save the line.

No, I'm not sayin to advance the catheter only, advance the whole unit. The purpose is to place the tip of the catheter onto to lumen while still over the needle. Then you slide the wire out and advance the catheter over the wire.

Sorry if this was not clear. Many attendings have told me to do it this way.
 
Try starting more proximal, away from the hand. Its easier to pass the wire and cath further up the arm away from the wrist bones. Also make sure you aren't getting too crazy with the wrist extension.
 
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Just do through and through from the get go, it's pretty awesome
 
Through and through failure for me. First time that has happened. I use it only as a rescue but with great success. Great exsanguinating pulsatilla flow out of the cath while pulling back. Thread the wire. Crunchy. Re thread. Crunchy. Re thread. Slightly less crunchy. Hopefully thread the catheter. No joy. Guy had a line in the same artery a month ago. Wonder if that made the difference here.
 
My 0.02 cents from a resident. So on device patients i.e. VADs etc. we use ultrasound routinely for a-lines, often brachial. I have started to use US for routine radial a-lines just for practice and to see what the screen shows compared to what I am feeling. It is amazing how elastic the artery can be in a young patient or calcified on the vasculopaths. I really try and skewer it with a short jabbing movement with real time US similar to a CVC. Backup plan is through and through when I know and can see that I went through the vessel on the screen. I apply these techniques to non-US a-line placements.
 
If the wire starts to feel even slightly "crunchy" as you advance it then the wire isn't in the vessel.

Yup, what BB said.

As an aside while where on the topic of A-lines, I've had instances using US in the SICU where I barely got a flash (if at all), but was directly visualizing my needle tip in the vessel. I've had some luck advancing the wire anyway and getting a good line. For what it's worth.
 
I go through and through from the get go. Separate angiocath and wire.

2 years ago I slowly switched from a .025g wire to a .021g wire.

.021g wire can sneak past plaque/resistance and guide your angiocath where it needs to go.
I also like the biofeedback I get from holding the wire itself.

Yeah, I do like that Microcatheter wire (not sure the gauge but it's smaller for sure than the standard Aero one). I agree in that it does allow you to bypass a severely stenotic vessel and does have better biofeedback, like you said.

Sometimes for better "feel", you can go through and through with the Aero angiocath set up, then withdraw the needle/wire/tube assembly, leaving the catheter through and through. You can use the scalpel to cut the end of the tube off, and then pull the guide wire out and use it stand alone for threading the wire as you pull back on the angiocath looking for blood. I've done this on occasion, for "better feel" but not sure it's necessary.
 
Just do through and through from the get go, it's pretty awesome

Not sure this is necessary if you have a really good pulsatile flow. Just too easy to attempt to thread the wire and if it goes smooth, it's a little faster NOT going through and through. I use T-T if I'm having difficulty mostly.
 
Just do through and through from the get go, it's pretty awesome

Like anything... the more you do the faster you will become. I'm all though and through as well. If I have any problems (very rarely...) I go right to USD which gets me a secured a-line always. I've had to go to the other side once or twice in 2012.

A-line, induction, tube, OG, TEE, prep, MAC, Swan... 15 minutes routinely.

No joke. (the proper OR team is key to achieve this)
 
Next time, get 5cc of heparin flush and aspirate your catheter to get good blood flow return and then flush the heparin saline into the artery. I find this is very useful during the times when your wire has resistance after using the through and through technique. Instead of forcing the wire, just hookup the heparin flush.. pull back and aspirate a bit till you get good flow and then flush slowly. You should get better artery backflow and be able to thread wire easily. I find this most useful on the vasculopaths or the little kids.
 
Like anything... the more you do the faster you will become. I'm all though and through as well. If I have any problems (very rarely...) I go right to USD which gets me a secured a-line always. I've had to go to the other side once or twice in 2012.

A-line, induction, tube, OG, TEE, prep, MAC, Swan... 15 minutes routinely.


No joke. (the proper OR team is key to achieve this)

Nice Sevo! Must be a good crew indeed.
 
15m holy crap.

I like thru and thru but I try to practice the one puncture technique to improve. I find that I can't wire the artery after a flash very frequently- I think my needle isn't fully into the lumen, so the wire exits superficial to the artery into nowhere. Advancing the needle after flattening out has not been great for me- if I have any issues, I back wall the artery.
 
Yup, what BB said.

As an aside while where on the topic of A-lines, I've had instances using US in the SICU where I barely got a flash (if at all), but was directly visualizing my needle tip in the vessel. I've had some luck advancing the wire anyway and getting a good line. For what it's worth.

This happens in the small babies most/all the time, I don't even go by flash just visualization of the needle tip in the center of the artery either radial ( norwoods ect) or fem lines
 
In adults an angiocath one puncture technique has worked well for me. After first flash (assuming a bevel up entry), stop and rotate the needle 180 degrees and advance the catheter into the vessel (i.e. no further advancement after flash). Spinning the needle 180 degrees prevents the proximal end of the artery from hanging up the catheter because having rotated, the longest part of the needle effectively stylets the catheter through the only part of the artery that you could get hung up on (the proximal side of the puncture). This seems to work 90% of the time.

Once I've gone to a through and through technique, threading a wire before I see pulsatility is usually a waste of time.
 
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In adults an angiocath one puncture technique has worked well for me. After first flash (assuming a bevel up entry), stop and rotate the needle 180 degrees and advance the catheter into the vessel (i.e. no further advancement after flash). Spinning the needle 180 degrees prevents the proximal end of the artery from hanging up the catheter because having rotated, the longest part of the needle effectively stylets the catheter through the only part of the artery that you could get hung up on (the proximal side of the puncture). .

wow, why are you guys making this so complicated? it's just an aline fer cryin out loud! keep it simple.

1) do it whatever way you want, but you need to do a lot to get good
2) can't get a radial? try with U/S or go somewhere else - brachial, femoral, omental...
3) can't get an aline anywhere? do the case without
4) can't do the case without? call someone else to try
5) if you get to this step pt's probably dead by now, so don't bother
 
wow, why are you guys making this so complicated? it's just an aline fer cryin out loud! keep it simple.

1) do it whatever way you want, but you need to do a lot to get good
2) can't get a radial? try with U/S or go somewhere else - brachial, femoral, omental...
3) can't get an aline anywhere? do the case without
4) can't do the case without? call someone else to try
5) if you get to this step pt's probably dead by now, so don't bother


The OP is having a hard time with radial arterial lines and was seeking suggestions. What have you provided that will help him?
 
The only thing recommended that I think doesn't work is to lower your angle after the flash. You are more likely to get a hematoma than to lower your angle while keeping the tip in the artery.
The most important thing is to know exactly where the artery is before you break skin.
Roll your finger over it on both sides where you plan to enter skin and an inch proximal.
Piercing the skin off to the side means you'll enter at 2 angles (up down and side to side) setting yourself up for failure.
If you have to fan around a bit that's ok but if you are aiming much to the side, just remove the cathether, recheck the location of the artery, and pick a better place to enter yhe skin.
I start with a very flat angle at the wrist or at 30-45* if starting more proximal.
 
In adults an angiocath one puncture technique has worked well for me. After first flash (assuming a bevel up entry), stop and rotate the needle 180 degrees and advance the catheter into the vessel (i.e. no further advancement after flash). Spinning the needle 180 degrees prevents the proximal end of the artery from hanging up the catheter because having rotated, the longest part of the needle effectively stylets the catheter through the only part of the artery that you could get hung up on (the proximal side of the puncture). This seems to work 90% of the time.

Once I've gone to a through and through technique, threading a wire before I see pulsatility is usually a waste of time.

I do the same 180 flip, but then advance everything (needle & catheter) another 1mm or so. Good results with it, especially in pediatric a-lines. If there's the slightest resistance threading the catheter off the needle, I'll stop, go through the back wall, take out the needle, back up the catheter until there's pulsatile flow, wire, catheter in.

Common mistake I see new people make is starting with this exaggerated steep approach, and then dropping the angle a lot once they get a flash. I start with about a 30 deg angle and leave it there.
 
very low angle, go where you feel it, dont overthink it, im talking 20 degrees, maximize your chances of hitting the artery at different depths as you advance with a shallow angle, with a steep angle easy to miss by a hair, and harder to threat the wire

once you have flash at a shallow angle, quickly advance the wire to the black line on the aero-kit, then, once you are passing the black line, the wire is coming out of the needle tip, go SLOW for this to let it just wiggle itself into the path of least resistance, so suuper slowly thread that wire at the shallow angle.

then as you advance the catheter over the wire, twist it clockwise spinning it into the artery smoothly

if you have resistance advancing the wire of catheter just pull your wire back and do through and through as others have mentioned, but I have had very high success with shallow angle, slow wire, twist catheter
 
Agree with all above- shallow angle , twist off and hit it right on center.from above, not the side..What helped me most was when I realized that MY index finger needed to be re-calibrated . What I thought was the middle of the artery by palpating was actually a tad lateral, so I had to recalibrate my brain/finger much like sighting in a rifle scope. I never really shared this until today, but it popped into my head reading the thread. I also used to use some ephedrine (5-10mg) if it was too thready.
 
..What helped me most was when I realized that MY index finger needed to be re-calibrated. What I thought was the middle of the artery by palpating was actually a tad lateral...

You're not the only one. One of my chief residents warned about this when I was a CA-1: he said the artery is usually a little more medial than you think.

If I use a doppler (incredibly rare), I stick where it sounds the loudest.
 
I like using the ultrasound. I've had several a lines where I get no flash, but my needle is in the artery; the wire threads and the catheter threads and I'm in the artery.
 
Why not usd?

I like Doppler. When I started training not that long ago it was much easier to get a doppler at my institution but by the time I was leaving ultrasound was taking over for tough a lines. I got pretty comfortable with the doppler and I liked not having to split my attention between the screen and the procedure site.

At my current gig it's a pain in the butt to find a doppler but we have lots of ultrasounds around. At my next gig it could be the opposite. I like being able to use both.
 
Why not usd?

It was easier to get a doppler on the occasions when I needed it. I've placed A-lines using U/S before -- enough to feel OK with it, but not many. Now that we have our own U/S machine, I should in theory use it for all A-line placements to develop proficiency, but I have fallen prey to old habits of doing it by feel.
 
I feel like it is viewed as a failure or deficiency in skills to grab a Doppler or ultrasound, at least at my shop. I don't understand this thinking. If I can't get a line in five minutes I will grab a Doppler because I know I can get an a-line in <3 min with a Doppler 90% of the time and I'd rather not flounder and take any longer than I have to. This even includes pts I can feel a pulse in. Sometimes the doppler helps. Whatever gets the job done.

My preference is usually Doppler over ultrasound at least initially for the same reasons MT mentioned. Always feels like a hassle to grab the ultrasound and I don't like averting my gaze from the needle and having to constantly look back and forth between the screen and my needle.
 
I feel like it is viewed as a failure or deficiency in skills to grab a Doppler or ultrasound, at least at my shop. I don't understand this thinking. If I can't get a line in five minutes I will grab a Doppler because I know I can get an a-line in <3 min with a Doppler 90% of the time and I'd rather not flounder and take any longer than I have to. This even includes pts I can feel a pulse in. Sometimes the doppler helps. Whatever gets the job done.

My preference is usually Doppler over ultrasound at least initially for the same reasons MT mentioned. Always feels like a hassle to grab the ultrasound and I don't like averting my gaze from the needle and having to constantly look back and forth between the screen and my needle.

That sounds harsh if it's viewed as failure or deficiency. If you don't want to avert your gaze, try doing the long axis in plane approach. You can see the needle the whole time on your screen. Its pretty gratifying seeing the needle and the tip of the catheter within the lumen of your artery. Interestingly, I've had multiple times where I use an ultrasound and see the needle and the catheter go in, without flash, proceed to advance wire and then catheter, then get blood flow. Maybe bypassing an atherosclerotic part of the vessel? Regardless, its a nice way to do it vs short axis out of plane.

To chime in, I think the through and through method for rescue is golden most of the time. I've had attendings who go straight for through and through with a pink angiocath (not the arrow catheters). Make sure to pull back slowly with wire in hand (and gauze to catch blood) and get good flow before passing wire. Obviously, be wary of doing that too often in your liver patients or people on anticoagulation for risk of hematoma,
 
I started my art lines going through and through. It's a good way to learn, and you can get pretty quick at them. The mess is a pain to clean up though.

I have had problems with arrow caths getting the wire hung up even though i have great pulsatile flow.

I had been using a regular 20 g angiocath. Going in at a steep angle, dropping to flat when I got a flash, and threading it straight in.

Now that I'm working with patients that have had millions of art lines, I do the same technique with an arrow. If the wire doesn't thread, then I go through and through. I advance the wire through the needle of the arrow, and use that through the catheter when I get pulsatile flow back.

I will try 2 or 3 times per wrist. Plan B is ultrasound. I turn the probe longitudinally and watch the needle go into the vessel. Thread the wire, push the catheter in. I have used that technique for radial, ulnar and brachial.
 
I started my art lines going through and through. It's a good way to learn, and you can get pretty quick at them. The mess is a pain to clean up though.

I have had problems with arrow caths getting the wire hung up even though i have great pulsatile flow.

I had been using a regular 20 g angiocath. Going in at a steep angle, dropping to flat when I got a flash, and threading it straight in.

Now that I'm working with patients that have had millions of art lines, I do the same technique with an arrow. If the wire doesn't thread, then I go through and through. I advance the wire through the needle of the arrow, and use that through the catheter when I get pulsatile flow back.

I will try 2 or 3 times per wrist. Plan B is ultrasound. I turn the probe longitudinally and watch the needle go into the vessel. Thread the wire, push the catheter in. I have used that technique for radial, ulnar and brachial.

The problem with 20g angiocaths is they are not resilient and are prone to kinking.

The 20g Arrow kit is much less prone to obstruction once placed.
 
The problem with 20g angiocaths is they are not resilient and are prone to kinking.

The 20g Arrow kit is much less prone to obstruction once placed.

YES. I had an attending in residency who on two occasions put in angiocaths when I couldn't get an Arrow in (good flow, couldn't thread wire). Neither a-line was functional by the end of the case. So if I get no love distally, I use ultrasound and go proximal or even brachial if I really want the A-line (i.e. heart room).

I know that's an n of 2 but it's not an experience I'd care to repeat.
 
I haven't found "averting my gaze" using the ultrasound to be an issue. Usually, I've got a nurse or an anesthesia tech who's plugged in the ultrasound machine and hands me the transducer. I just look at the screen and they can tell me when I get a flash, but typically I hit my target on ultrasound, look down at the wrist, see flash, and proceed.
 
In general, the pts I am putting in A-lines are my MICU pts that I am titrating pressors on. So by definition, they all have triple lumens as well. Normally, this is an US guided IJ. Of late, seeing as I already have the US draped and at bedside, I have just been prepping the right forearm out on an armboard at the same time I prep the neck. i then throw in the triple lumen, move over 3 feet to the arm, and use the US to throw in the A-line about 2/3 of the way up to the antecub from the wrist. The deeper larger vessel seems to be much easier to hit with the US, is far less tortuous and I almost always get it in one stick and have no problems. Of note, I also only use the arrow kit as my patients generall need that line for several days and the angiocaths never last. however, you gas guys put in alot of A-lines in the OR in pts that dont need TLCs so this may not be as practical for you.
 
Naturally after that last post, I need an a-line tonight, stuck the probe on and saw a feebly radial. Minimal if any pulse in the wrist, he had coded earlier and was on NE and vaso, RT never even got a post tube ABG. Located it with US, stuck, filled the arrow kit nicely with blood, wire wouldnt feed. Fumbled with it a bit and wouldnt go. Withdrew, grabbed a new kit and when I re-examined and went to stick a little more cephalad, sure as **** that sucker was spasm'd shut. FML. Could literally see the artery rolling to the side and quivering closed when I touched the wall with the needle tip.
He is going to die in the next few hours anyway so I through in a fem line next to his fem TLC. Was dissatisfying though.
 
No, I'm not sayin to advance the catheter only, advance the whole unit. The purpose is to place the tip of the catheter onto to lumen while still over the needle. Then you slide the wire out and advance the catheter over the wire.

Sorry if this was not clear. Many attendings have told me to do it this way.

Nope. I was unclear. Get the flash. Don't move the needle, or the catheter or the whole unit, ONLY thread the wire. Once the wire is in, just thread the catheter off the needle. The belief that you need to advance the catheter with the needle in unison to enter the artery either before or after the wire is in is false. Try it.
 
The problem with 20g angiocaths is they are not resilient and are prone to kinking.

The 20g Arrow kit is much less prone to obstruction once placed.

agreed. im a ninja with the angiocath and no wire, but those things invariably quit working 90 minutes into a AAA repair.
 
I do adult a lines all the time, but struggled yesterday with a 3 y.o. (crani). I got a 22g in the foot but just could not hit the radial.
 
I do adult a lines all the time, but struggled yesterday with a 3 y.o. (crani). I got a 22g in the foot but just could not hit the radial.

my strategy for small kids:

- h/o previous aline or abg's - straight to ultrasound
- no h/o arterial sticks but pulse thready - straight to ultrasound
- no h/o arterial sticks and good pulse (most kids fall in this category) - no ultrasound

i always go through and through and wire while pulling back (in kids). it is more difficult to thread a wire or catheter while advancing because you are pushing the arterial walls together. when pulling a catheter back the friction pulls the walls apart and increases the success rate. the ulnar artery is often overlooked in kids. it is surprising how often there is no flash while using ultrasound but success is found after visualizing the needle pass through the artery, and then blood is found during withdrawal of the catheter prior to wiring.

if not soon successful after exploring the other sites i have a low threshold to ask someone else to take a poke. if still not successful and the aline is truly necessary our surgeons are happy to cutdown.
 
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