Arterial line - no flash

[Propofool123]

CA3 here - Have had a few instances now where I’ve done arterial lines either by palpation or ultrasound where i don’t have any flash. The times when I use ultrasound i clearly see I’m in the artery, there’s no flash, but i continue to follow my needle tip into the vessel and then thread the wire, slip in the catheter, and I have a great arterial waveform on the monitor. No flash or very minimal flash. Pressure is totally normal and they’re usually not really on pressors. Thoughts on why this happens?

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[Twiggidy]

Occasionally if the wire is down just a little bit while you’re inserting into the vessel you won’t see any flash despite being in. I always double check the wire is fully withdrawn before I start.

 

[nimbus]

I’ve had same experience a handful of times with the Arrow catheter. I trust the ultrasound. Only reason I think it might happen is a tissue plug at the end of the inner needle.

 

[coffeebythelake]

Rare occurrence. I think only happened once before for me and position was visibly appropriate under ultrasound, good waveform afterwards like u describe. Maybe brief spasm? Tiny vessel? I can't say for sure

 

[deleted875186]

Happened a couple times to me .... more likely you get a small amount of blood, nothing pulsation or filling, out the wire or advance catheter and it works great.

maybe tissue plug on the needle, maybe tiny lumen where you entered and or spasm, maybe a bit of plaque on the tip of the needle, who knows. Makes you wonder, all those times you stuck blindly and didn’t get flash, maybe you actually hit the vessel.

 

[drmwvr]

Angle of attack so acute as to tack the fore wall to the back wall with the needle? I think folks starting out perforate the artery several times this way not realizing they've been through and through at least once or twice. The worse the vascular dz the more likely it is to happen, IME.

 

[sleepallday]

What twiggidy said about the guide wire not being all the way up. But also I've noticed that the catheter itself can slip down a few millimeters and obstruct the opening of the needle. Especially when multiple passes are needed.

 

[AdmiralChz]

This is super rare. Had it happen a few weeks ago while using ultrasound - threaded and great blood return. Suspect something like a tissue plug as it took several attempts. Happened once before in residency.

I would never go for this without ultrasound confirmation.

 

[abolt18]

Happened to me once or twice. As noted above, I'm assuming just some sort of tissue plug in the needle. Saw I was in on ultrasound. Went with it. Worked fine. When someone has very tough skin, I do occasionally use an 18g needle to break the skin first because the arrow seems to not be sharp enough.

 

[Southpaw]

Almost certainly tissue or wire obstruction. I’ve had it happen. The arrow cath needle is pretty dull relative to an angiocath.

 

[MirrorTodd]

Coincidentally JUST had this happen this morning. I tried twice, 18g angiocath, no U/S. Attending steps in, twice with a 20g angiocath, no U/S, finally with U/S, confirmed needle in artery thread up greater about halfway, wire slides in fine. No severe calcifications on U/S, both of us attempted with angiocaths, he even took the flash chamber stopper off, but we just never had a flash. Guy had an excellent pulse, shoulda been a straight shot.

 

[Southpaw]

Coincidentally JUST had this happen this morning. I tried twice, 18g angiocath, no U/S. Attending steps in, twice with a 20g angiocath, no U/S, finally with U/S, confirmed needle in artery thread up greater about halfway, wire slides in fine. No severe calcifications on U/S, both of us attempted with angiocaths, he even took the flash chamber stopper off, but we just never had a flash. Guy had an excellent pulse, shoulda been a straight shot.

this is why I personally use US, or have it available, for every Aline I do. I consider it a smart and efficient use of my time as opposed to weakness.

 

[Drfirextinguisher]

Coincidentally JUST had this happen this morning. I tried twice, 18g angiocath, no U/S. Attending steps in, twice with a 20g angiocath, no U/S, finally with U/S, confirmed needle in artery thread up greater about halfway, wire slides in fine. No severe calcifications on U/S, both of us attempted with angiocaths, he even took the flash chamber stopper off, but we just never had a flash. Guy had an excellent pulse, shoulda been a straight shot.

Are you going old school (regular iv)? If so you may have the anti-bleed back technology. I’ve had this happen before where they switched iv models on us & it took me a sec to realize why I didnt get any flash.

 

[GassYous]

this is why I personally use US, or have it available, for every Aline I do. I consider it a smart and efficient use of my time as opposed to weakness.

Also you can bill for it!

 

[Twiggidy]

Coincidentally JUST had this happen this morning. I tried twice, 18g angiocath, no U/S. Attending steps in, twice with a 20g angiocath, no U/S, finally with U/S, confirmed needle in artery thread up greater about halfway, wire slides in fine. No severe calcifications on U/S, both of us attempted with angiocaths, he even took the flash chamber stopper off, but we just never had a flash. Guy had an excellent pulse, shoulda been a straight shot.

This just may be a difference in training but may I ask, why an 18g for an A line? I’ve just never needed that gauge of an a line especially in a radial so I’m just curious the rationale

 

[abolt18]

This just may be a difference in training but may I ask, why an 18g for an A line? I’ve just never needed that gauge of an a line especially in a radial so I’m just curious the rationale

Also never used bigger than a 20g for radial arterial line.

 

[deleted162650]

Coincidentally JUST had this happen this morning. I tried twice, 18g angiocath, no U/S. Attending steps in, twice with a 20g angiocath, no U/S, finally with U/S, confirmed needle in artery thread up greater about halfway, wire slides in fine. No severe calcifications on U/S, both of us attempted with angiocaths, he even took the flash chamber stopper off, but we just never had a flash. Guy had an excellent pulse, shoulda been a straight shot.

Try flushing the angiocath first. It breaks the surface tension so you get a much more rapid/robust flash. Especially helpful with hypotension or a low CO patient situation.

 

[MirrorTodd]

Try flushing the angiocath first. It breaks the surface tension so you get a much more rapid/robust flash. Especially helpful with hypotension or a low CO patient situation.

Ah ok, I wondered why they always had us flush it when I rotated at Childrens

 

[MirrorTodd]

Are you going old school (regular iv)? If so you may have the anti-bleed back technology. I’ve had this happen before where they switched iv models on us & it took me a sec to realize why I didnt get any flash.

I dont think so. As far as I know, catheters are all still the same. They're the spring loaded safety style IV catheters. We also have the non safety style just straight needle, catheter and flash chamber.

 

[MirrorTodd]

This just may be a difference in training but may I ask, why an 18g for an A line? I’ve just never needed that gauge of an a line especially in a radial so I’m just curious the rationale

18g is attending preference where I am rotating right now. Other places just use a 20g. Also may be showing us different techniques too. We do our central lines using landmarks, although we cheat a little bit and attending scans while I gown.

 

[Twiggidy]

18g is attending preference where I am rotating right now. Other places just use a 20g. Also may be showing us different techniques too. We do our central lines using landmarks, although we cheat a little bit and attending scans while I gown.

Strange. But hey, I get it as you have to do what your attending wants you to do. Seriously, if you’re going to scan the neck why not just drape it and use it during insertion. Don’t question your attending and get yourself in trouble, but just keep these pearls in mind when you start practice or if with an attending that lets you work a little more independent.

 

[Urzuz]

18g is attending preference where I am rotating right now. Other places just use a 20g. Also may be showing us different techniques too. We do our central lines using landmarks, although we cheat a little bit and attending scans while I gown.

Are you doing a cardiac rotation at a neighboring hospital system?

Your experiences sound identical to mine when I was a resident.

 

[coffeebythelake]

Are you going old school (regular iv)? If so you may have the anti-bleed back technology. I’ve had this happen before where they switched iv models on us & it took me a sec to realize why I didnt get any flash.

They switched these recently at my hospital. We have the BD insyte IV cannulas.. Always used to apply pressure to an IV when taking out the needle.

 

[MirrorTodd]

Strange. But hey, I get it as you have to do what your attending wants you to do. Seriously, if you’re going to scan the neck why not just drape it and use it during insertion. Don’t question your attending and get yourself in trouble, but just keep these pearls in mind when you start practice or if with an attending that lets you work a little more independent.

Agreed, I may end up doing the rare landmark technique in the future so I'm glad I'm learning it now, but I'll be using ultrasound in my own practice next year for the most part.

 

[MirrorTodd]

Are you doing a cardiac rotation at a neighboring hospital system?

Your experiences sound identical to mine when I was a resident.

I did cardiac here last March. It's really an "advanced" rotation but do a fair amount of cardiac since they don't get vats etc coming in every day. Let's just say hypothetically that you maybe rotated at a Jewish hospital?

 

[Hork Bajir]

18g catheter for radial art lines is associated with a higher rate of arterial thrombosis and occlusion than with 20g catheters, with no benefit to the larger catheter.

if I were you, I would print this paper out and bring it to your attending:
18 vs 20g arterial lines

If he or she is willing to have a discussion about it and explain their rationale, great- learning has taken place. If not, then you have learned something about that person’s judgement and reasoning. You can use that information to filter and categorize everything else they tell you. Sometimes as a resident you just have to smile and nod, but it’s incumbent upon you to discern the truth from the bull****

 

[sevoflurane]

Ya. 18g unnecessary and prone to failure. If you can’t get radial with a 20g, just go brachial.

 

[Urzuz]

I did cardiac here last March. It's really an "advanced" rotation but do a fair amount of cardiac since they don't get vats etc coming in every day. Let's just say hypothetically that you maybe rotated at a Jewish hospital?

ah must be a different residency. Was not at a Jewish hospital.

 

[kidthor]

I've had this happen before with someone who asystolic undergoing ACLS. Otherwise there's at least a splash of blood in the catheter.

 

[dchz]

Great discussion so far. In my mind there are several possibilities:

1. As @Twiggidy and others pointed out, it's most likely something obstructing the opening of the needle.

2. Your needle looks to be in the middle of the artery, but it has not punctured through the artery yet. The act of threading the wired may puncture the arterial wall or a lot of times I noticed if you just hold the needle in the same spot the arterial pressure will push the walls back and puncture the needle.

I noticed phenomenon #2 a lot in younger people with very muscular arteries.

How I became aware of this: I used a lot of kits that has a needle by itself and require separate wire to be threaded. To make my first time wire thread rate near 100%, I advance the needle about 1 cm along the artery under ultrasound. Even when the tip of the needle is dead middle of the artery, once I advance the needle a few mm, I feel a tactile "pop" before I get flashback. In this case the wire is not there to obstruct the backflow and when it flashes back there certainly wasn't any tissue in the blood container, that along with the tactile pop made me realize we may not see the entire picture under ultrasound. Which is why I always advocate advancing the needle tip under the ultrasound.

 

[deleted875186]

Great discussion so far. In my mind there are several possibilities:

1. As @Twiggidy and others pointed out, it's most likely something obstructing the opening of the needle.

2. Your needle looks to be in the middle of the artery, but it has not punctured through the artery yet. The act of threading the wired may puncture the arterial wall or a lot of times I noticed if you just hold the needle in the same spot the arterial pressure will push the walls back and puncture the needle.

I noticed phenomenon #2 a lot in younger people with very muscular arteries.

How I became aware of this: I used a lot of kits that has a needle by itself and require separate wire to be threaded. To make my first time wire thread rate near 100%, I advance the needle about 1 cm along the artery under ultrasound. Even when the tip of the needle is dead middle of the artery, once I advance the needle a few mm, I feel a tactile "pop" before I get flashback. In this case the wire is not there to obstruct the backflow and when it flashes back there certainly wasn't any tissue in the blood container, that along with the tactile pop made me realize we may not see the entire picture under ultrasound. Which is why I always advocate advancing the needle tip under the ultrasound.

Great tip, I too have noticed a tactile pop when advancing under US, even after the tip appears in the center And the vessel doesn’t look indented.

 

[MoMoGesiologist]

Ya. 18g unnecessary and prone to failure. If you can’t get radial with a 20g, just go brachial.

Everyone here is so scared of brachials! Makes me feel like if I do one and get a complication, itll be “I told you so!” all around

 

[deleted697535]

We do our central lines using landmarks, although we cheat a little bit and attending scans while I gown.

This is interesting. Im glad they are willing to put so much on the line like that. Outside of a life or death situation, no-one will support that if you hit the carotid without ultrasound. It is indefensible but im glad people continue to teach it


Re no flash - reasonably common. Maybe 1 in 10 of our cardiac cripples have no flow in a variety of their 'limbs' at a variety of distances from the heart. Some have great flow in brachials yet nada at the wrist

Or even more common, you're not 'in'. uss Artifact makes it seem youre in, or you're missing something. aline are a mofo lol. Hardest skill. Ive done 1000s and im getting schooled every day lol

Best tip - use 'nitro'caine

 

[sevoflurane]

Everyone here is so scared of brachials! Makes me feel like if I do one and get a complication, itll be “I told you so!” all around

Nah. Never had a brachial complication over the last 15 years of doing them. Doesn’t cleaveland clinic do them routinely for pump cases?

 

[GassYous]

Nah. Never had a brachial complication over the last 15 years of doing them. Doesn’t cleaveland clinic do them routinely for pump cases?

We had a bunch of brachial a lines done with no issues. We also used to put in a lines on both sides for robot cardiac and we still do b/l radial a lines for our livers. No issues as well. But one time a hypercoaguable trauma patient clotted off their brachial artery and everyone tried to blame it on the radial a line. Made zero sense.

 

[deleted697535]

Nah. Never had a brachial complication over the last 15 years of doing them. Doesn’t cleaveland clinic do them routinely for pump cases?

Absolutely. If i hear another motherucking generalist tell me the brachial art is an end artery and have to avoid it for a lines I effing lose it... Our biggest cases pte's, type a$, triple valves impellas all get brachials without losing digits...
It does irk me when people make up ****ty so called 'rules' based on nothing except their own ocd/stupidity. Like norepi can't go peripherally, no BP after breast surgery, no cepbalosporin if pcn allergy bla bla bla...

 

[Twiggidy]

Everyone here is so scared of brachials! Makes me feel like if I do one and get a complication, itll be “I told you so!” all around

i was always nervous about them too until i got a blessing from a vascular surgeon. i think radial hematomas and artery dissections bothered him more that a 20g in what is usually a fairly large artery, especially in his patient population. the small gauge of the catheter and the fact they usually aren’t in more than 48 hrs results in less chance of thrombosis.

 

[OneTyme]

This is interesting. Im glad they are willing to put so much on the line like that. Outside of a life or death situation, no-one will support that if you hit the carotid without ultrasound. It is indefensible but im glad people continue to teach it


Re no flash - reasonably common. Maybe 1 in 10 of our cardiac cripples have no flow in a variety of their 'limbs' at a variety of distances from the heart. Some have great flow in brachials yet nada at the wrist

Or even more common, you're not 'in'. uss Artifact makes it seem youre in, or you're missing something. aline are a mofo lol. Hardest skill. Ive done 1000s and im getting schooled every day lol

Best tip - use 'nitro'caine

OK, I give (couldn’t find googling)

wtf is nitrocaine?

 

[nimbus]

OK, I give (couldn’t find googling)

wtf is nitrocaine?

NTG+lidocaine

Can also use papaverine+lidocaine.

I don’t use either but our cardiologists infiltrate it to dilate the vessel for easier cannulation and to prevent radial artery spasm when they do their transradial PCI’s.

 

[abolt18]

OK, I give (couldn’t find googling)

wtf is nitrocaine?

Cards uses all the time. Have done it myself. Just added a little NTG to my lido (4cc of 1% + 1cc of 200mcg/ml NTG). Do your injection under ultrasound and inject down to and around both sides of the artery.

 

[Hork Bajir]

Assuming no intravascular injection, is there any noticeable systemic effect from the nitro, either delayed or immediate?

 

[Southpaw]

for those using nitrocaine, how do you get it? drawing it up out of a bottle of nitro for a couple alines a day seems wasteful. is your hospital giving it to you in prefilled syringes?

 

[dchz]

This is interesting. Im glad they are willing to put so much on the line like that. Outside of a life or death situation, no-one will support that if you hit the carotid without ultrasound. It is indefensible but im glad people continue to teach it

Why is it a big deal if you hit the carotid?

NTG+lidocaine

Can also use papaverine+lidocaine.

I don’t use either but our cardiologists infiltrate it to dilate the vessel for easier cannulation and to prevent radial artery spasm when they do their transradial PCI’s.

This is another point I want to bring up. As my technical skills gotten better, it's more of a question of "should I do this?" rather than "can I do this?"

A few years ago, I would give myself a huge fist bump if I could get the catheter in a small artery. It got to a point I would find the smallest artery I could find just to try to cannulate it.

I'm now at the point in my life where I see an calcified artery of smaller caliber, even if I know I can cannulate it, I'd still just go to the brachial. It's just better for the patient - less chance of failed cannulation, hematomas, or needle dissection of the arm. I feel like if you have to use nitrocaine to put a 20g catheter in, you should probably find a bigger artery. It's different for the interventional cards because they have much more to gain from avoiding groin cannulation. Also their equipment is a bigger caliber than 20g.

 

[deleted162650]

Great discussion so far. In my mind there are several possibilities:

1. As @Twiggidy and others pointed out, it's most likely something obstructing the opening of the needle.

2. Your needle looks to be in the middle of the artery, but it has not punctured through the artery yet. The act of threading the wired may puncture the arterial wall or a lot of times I noticed if you just hold the needle in the same spot the arterial pressure will push the walls back and puncture the needle.

I noticed phenomenon #2 a lot in younger people with very muscular arteries.

How I became aware of this: I used a lot of kits that has a needle by itself and require separate wire to be threaded. To make my first time wire thread rate near 100%, I advance the needle about 1 cm along the artery under ultrasound. Even when the tip of the needle is dead middle of the artery, once I advance the needle a few mm, I feel a tactile "pop" before I get flashback. In this case the wire is not there to obstruct the backflow and when it flashes back there certainly wasn't any tissue in the blood container, that along with the tactile pop made me realize we may not see the entire picture under ultrasound. Which is why I always advocate advancing the needle tip under the ultrasound.

Why use a wire if you’re using U/S? In-plane advance angiocath well into vessel at shallow angle, thread off cath, done.

No U/S I go through and through with a wire. With U/S as above.

 

[dchz]

Why use a wire if you’re using U/S? In-plane advance angiocath well into vessel at shallow angle, thread off cath, done.

No U/S I go through and through with a wire. With U/S as above.

The kit is designed without a catheter over the needle.

Some places uses the argon 6 inch or cook micropuncture kits for big cases and if the a line is expected to stay in for days to a week. A lot less chances of getting it accidentally pulled out. It's much easier to pull out 1.5 inches than to pull out 6 inches. Giggity.

Also I still use the wire even if I do US guided with arrow kits, it's one more fail prevention and test the placement of needle tip. It takes one second to push the wire in because you're already oriented parallel in the artery. And it also gives you a longer shaft as a guide. Giggity.

 

[Norepi]

Had this happen - jab the 20g angiocath under ultrasound guidance forward while keeping tip in vessel center. You need to dislodge whatever intima or else is plugging the tip.