Arterial lines stop working

[deleted875186]

I’ve had a case recently we’re my radial art line stopped working mid case. Attending thought I punctured at too steep an angle, but I’ve always used about 45 degree angle and then flattened. I generally use the arrow radial kits. Anyone have an idea about why arterial lines stop working, or am I actually going too steep?

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[CopaceticOne]

When you say it stopped working, what actually happened? In my limited experience there's an evolution of changes that occur before saying it is now crap.

 

[shepardsun]

As an aside to this, I'm currently a CA1 and have been placing my A-lines with the "45 degree angle initial insertion, drop and advance once you get the flash" technique I was taught at the beginning of the year. I worked with a cardiac attending for the first time a little while ago and had to do some pre-induction lines, at which point I was told that I should start them at the low angle to begin with and that the drop could lead to through and throughing or shearing of the vessel wall. Thoughts?

 

[T-burglar]

It’s hard to know why a lines crap out, we use long 10 cm catheters (femoral catheters) for all our radials and brachial and it’s so rarely an issue that we haven’t even thought about changing our practice.

In training however we used the short arrow catheters and they crapped out so much. It seems to be related to catheter length.

 

[deleted875186]

When you say it stopped working, what actually happened? In my limited experience there's an evolution of changes that occur before saying it is now crap.

By stop working ... I mean I look over at the monitor and it’s slightly dampned .... I’ll flush it ..... then 10-15 mins later it is completely dampened and reading an erroneously low MAP, now not improving with flushing, try to draw back blood and nothing. Catheter was in the vessel tj start and spitting blood, and now who knows.

This just happened the other day with an LVAD patient .... radial art line lasted all of maybe 5 minutes before it crapped out, even thought it was spurting blood to begin with.

 

[deleted162650]

By stop working ... I mean I look over at the monitor and it’s slightly dampned .... I’ll flush it ..... then 10-15 mins later it is completely dampened and reading an erroneously low MAP, now not improving with flushing, try to draw back blood and nothing. Catheter was in the vessel tj start and spitting blood, and now who knows.

This just happened the other day with an LVAD patient .... radial art line lasted all of maybe 5 minutes before it crapped out, even thought it was spurting blood to begin with.

Sometimes vessel spasm. Sometimes the catheter gets kinked - gotta inspect it real close to make sure it didn’t fold back on itself at the insertion site.

 

[facted]

Longer catheters usually better. Personally, I like to keep the patients wrist at the same angle it was when I put the line in (i use a wrist board). Also, tape with a mesentery as opposed to taut which helps to stop the kinking.

 

[deleted697535]

Its usually clot. Sometimes on position change its the cannula kinking on itself where you taped it to the skin. Sometimes its electronic error with a wire disconnected or fluid in between the contacts

There are rescue technqiues like making sure the bag is pumped to 300mmHg, disconnecting everything as close to the skin as possible. You can try rewire the cannula.
If its initially 'in' the artery, its very rare that it would pop 'out' unless you're brachial in a fat arm with a short cannula

I dont know why but every single art line i ever put in on OB died at 24 hours. Fecking nurses just never flushed the line after blood draws, or pumped the bag. It drove me nuts

 

[Ronin786]

I call BS on the angle of puncture having anything to do with it. If you're in the artery, you're in the artery.

Radial a-lines will crap out even if they're single shot and easy. A beginner move is starting real close to the wrist and having it kink when the wrist bends. That can be avoided by going more proximally (to the direction of the elbow). Otherwise, nothing you can do about vessel spasm as mentioned above, maybe rewiring but difficult to do if the arms aren't out.

 

[nimbus]

Sometimes vessel spasm. Sometimes the catheter gets kinked - gotta inspect it real close to make sure it didn’t fold back on itself at the insertion site.

And sometimes intimal dissection that spreads.

 

[dhb]

Anatomy can be a factor: i remember putting in a radial line really easily but the last couple of mm of the catheter wouldn't go in and the waveform would flatten.
On US you could see the distal radial artery branching at a steep angle into the more proximal part.

 

[anbuitachi]

try injecting some nitro?

 

[btbam]

try injecting some nitro?

Or Lido.

 

[jonessoda1212]

On the babies, we often put Papaverine in the fluid running through the arterial line.

 

[Urzuz]

By stop working ... I mean I look over at the monitor and it’s slightly dampned .... I’ll flush it ..... then 10-15 mins later it is completely dampened and reading an erroneously low MAP, now not improving with flushing, try to draw back blood and nothing. Catheter was in the vessel tj start and spitting blood, and now who knows.

This just happened the other day with an LVAD patient .... radial art line lasted all of maybe 5 minutes before it crapped out, even thought it was spurting blood to begin with.

You do know that arterial waveform "dampening" (i.e.: pulse pressure narrowing) in an LVAD patient may not be a problem with the arterial line, right...?

In any event, next time try making a small mesentery under the catheter as it is entering the skin by pinching the tegaderm together around the catheter (not sure if you can visualize what I'm suggesting). This was a little trick that one of my old school attendings showed me in residency that works more often than not.

 

[MirrorTodd]

You do know that arterial waveform "dampening" (i.e.: pulse pressure narrowing) in an LVAD patient may not be a problem with the arterial line, right...?

In any event, next time try making a small mesentery under the catheter as it is entering the skin by pinching the tegaderm together around the catheter (not sure if you can visualize what I'm suggesting). This was a little trick that one of my old school attendings showed me in residency that works more often than not.

Does that keep it elevated off the skin at the site of entry or something?

 

[urge]

By stop working ... I mean I look over at the monitor and it’s slightly dampned .... I’ll flush it ..... then 10-15 mins later it is completely dampened and reading an erroneously low MAP, now not improving with flushing, try to draw back blood and nothing. Catheter was in the vessel tj start and spitting blood, and now who knows.

Too much vasoconstriction?

Doubt it's the angle if you are using arrow catheters.

 

[deleted162650]

Does that keep it elevated off the skin at the site of entry or something?

It maintains the angle of entry so the catheter doesn't have to bend and possibly kink like it would if you taped the hub down tight to the skin.

 

[bcat85]

Anecdotally, this seems to happen to me more frequently when the puncture site is too distal (right at the wrist) as opposed to 3-4 cm up the arm. It makes the line much more positional, so that when the arms are tucked, the surgeon leans on it, etc it is more likely to give out.

 

[nimbus]

This is why 2 or 3 Aline’s are better than one

I have only ever started with >1 Aline for hearts. But if I had a long case, with poor access to the patient, where a functional Aline was important, I would consider a second Aline up front. A few times I have inserted DP Aline’s during craniotomies when the radial Aline craps out.

 

[D P356]

PEA can cause the waveform to dampen....