Epi in nerve blocks?

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stephenpatrickd

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Hello all,
Thoughts on adding epi to local for nerve blocks with the goal of detecting intravascular injection?
Thanks much,
Spd

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Are you using an ultrasound, or a nerve stimulator alone?
 
Yes this is a normal and viable option if you want to do it. I do it sometimes for my supraclavicular nerve blocks with 0.25% bupi and 1:200,000 epi.
 
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Nah. Just use an ultrasound and aspirate before injection
 
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Hello all,
Thoughts on adding epi to local for nerve blocks with the goal of detecting intravascular injection?
Thanks much,
Spd
I have one attending who likes to do this. No other attendings do though.
 
I routinely add epi (all of our local is supplied plain, so I add 150 mcg epi to a 30 mL vial of local to get the desired 1:200,000 concentration)
 
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I use it for the duration action
Literally everything I've read indicates that this really isn't a thing if you're blocking with bupivacaine or ropivacaine. There is negligible to zero measurable difference in duration of action when using these LAs.

"Local Anesthetic Peripheral Nerve Block Adjuvants for Prolongation of Analgesia: A Systematic Qualitative Review" Local Anesthetic Peripheral Nerve Block Adjuvants for Prolongation of Analgesia: A Systematic Qualitative Review


"Epinephrine Does Not Prolong the Analgesia of 20 mL Ropivaca... : Anesthesia & Analgesia" https://journals.lww.com/anesthesia..._does_not_prolong_the_analgesia_of_20.60.aspx
 
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If you are using U/S and you are concerned about intravascular injection, the answer is to get better at U/S, not to add epi.
 
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But does it?

To Clarify:

Epi is not used to identify intravascular injection - agree that's what US and aspiration is for.

The absolute number of mg of bupivicaine is responsible for longer block duration - thats what im going for.

The maximum recommended dose of local anesthetic (mg/kg) is higher with solutions containing epi.

Therefore, with local with epi, I am able to give a higher dose of marcaine overall.

This high dose leads to fast block onset, longer duration, and because of the epi, still within the recommended dosage on a mg/kg basis.

Sometimes, when enough kg are present, I'll give two separate 20ml 0.5% injections (fem block and pop block) for complex knees.

That's a lot of local and I feel better that epi is in the mix
 
To Clarify:

Epi is not used to identify intravascular injection - agree that's what US and aspiration is for.

The absolute number of mg of bupivicaine is responsible for longer block duration - thats what im going for.

The maximum recommended dose of local anesthetic (mg/kg) is higher with solutions containing epi.

Therefore, with local with epi, I am able to give a higher dose of marcaine overall.

This high dose leads to fast block onset, longer duration, and because of the epi, still within the recommended dosage on a mg/kg basis.

Sometimes, when enough kg are present, I'll give two separate 20ml 0.5% injections (fem block and pop block) for complex knees.

That's a lot of local and I feel better that epi is in the mix
So,
1) Where do you live that you have a patient population coming for knees that is small enough you have to worry about 40 ml?
2) Are you hiring?
 
So,
1) Where do you live that you have a patient population coming for knees that is small enough you have to worry about 40 ml?
2) Are you hiring?

LOL. I’m lucky enough to practice where most of my patients are not super obese. However, when I do get a morbidly obese patient, I always get a kick out of it when the surgeon looks at me with his 30mL syringe and asks

“How much of this can I give?”

Me: “120”
 
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To Clarify:

Epi is not used to identify intravascular injection - agree that's what US and aspiration is for.

The absolute number of mg of bupivicaine is responsible for longer block duration - thats what im going for.

The maximum recommended dose of local anesthetic (mg/kg) is higher with solutions containing epi.

Therefore, with local with epi, I am able to give a higher dose of marcaine overall.

This high dose leads to fast block onset, longer duration, and because of the epi, still within the recommended dosage on a mg/kg basis.

Sometimes, when enough kg are present, I'll give two separate 20ml 0.5% injections (fem block and pop block) for complex knees.

That's a lot of local and I feel better that epi is in the mix

Absorption is not that great in the lower extremities. Epi doesn't do much for you. You can put in 20 and 20 without worrying about it. You would probably come down with LAST yourself if you knew how much local surgeons used to put in joints in the past.
 
If you are using U/S and you are concerned about intravascular injection, the answer is to get better at U/S, not to add epi.

I’m great with ultrasound (toot toot). But, I had an adductor recently with negative aspiration but significant heart rate change after 5-10 ccs of injectate. Easily saved me from a disaster.

Can someone convince me why I shouldn’t be putting epi in my blocks?
 
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To Clarify:

Epi is not used to identify intravascular injection - agree that's what US and aspiration is for.

I’m willing to bet that the vast majority of occurrences of LAST are following a negative aspiration. Does anyone inject following + heme? Lol. Epi is a fantastic IV indicator.
 
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Apparently not. ;) :poke:




There is some (admittedly weak) data that epi increases chances of nerve injury.

That adductor — good local spread on U/S. My guess is I had a venous puncture and withdrew the needle some. Probably had some local track back through. Point is, good spread on U/S isn’t a sure thing.

Epi is great.
 
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With lido - yes.

With bupi - no.

why do you believe this to be true?

many sources indicate increased bupi maximum dose with epi vs not.. and why would it make sense for lido and not bupivicaine?
 
many sources indicate increased bupi maximum dose with epi vs not

Can you please provide one of these sources. I have never seen a published max dose for bupi with epi v bupi w/o epi.

Sure it might make physiologic sense, but how much of a difference does it make? 1mg/kg, 2mg/kg, 12mg/kg???

If you’re going to make the (unconventional) claim, the onus is on you to provide the proof.
 
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Can you please provide one of these sources. I have never seen a published max dose for bupi with epi v bupi w/o epi.

Sure it might make physiologic sense, but how much of a difference does it make? 1mg/kg, 2mg/kg, 12mg/kg???

If you’re going to make the (unconventional) claim, the onus is on you to provide the proof.
just google it, many sources come up, but here's one:


many list 2-2.5 without epi, 2.5-3 with epi.. this was something i just always assumed , epi stops the vascular uptake of all LAs and thus prolongs the action
 
To Clarify:

Epi is not used to identify intravascular injection - agree that's what US and aspiration is for.

The absolute number of mg of bupivicaine is responsible for longer block duration - thats what im going for.

The maximum recommended dose of local anesthetic (mg/kg) is higher with solutions containing epi.

Therefore, with local with epi, I am able to give a higher dose of marcaine overall.

This high dose leads to fast block onset, longer duration, and because of the epi, still within the recommended dosage on a mg/kg basis.

Sometimes, when enough kg are present, I'll give two separate 20ml 0.5% injections (fem block and pop block) for complex knees.

That's a lot of local and I feel better that epi is in the mix
Im glad you clarified that for us...
 
just google it, many sources come up, but here's one:


many list 2-2.5 without epi, 2.5-3 with epi.. this was something i just always assumed , epi stops the vascular uptake of all LAs and thus prolongs the action

That's not a source. I'm with salty. And I was trained by a few of the authors that are mentioned in their references section. Epi doesn't help bupi and can possibly damage nerves from what I've read. I put it with my lido in neuraxial but don't use it besides that.
 
That's not a source. I'm with salty. And I was trained by a few of the authors that are mentioned in their references section. Epi doesn't help bupi and can possibly damage nerves from what I've read. I put it with my lido in neuraxial but don't use it besides that.
Anyone with data regarding nerve injury associated with epi addition to blocks?

And are you guys not adding epi because of the concern for injury... or because of the extra step? I’m trying to quantify the downside in my mind. It appears minimal.
 
And are you guys not adding epi because of the concern for injury... or because of the extra step? I’m trying to quantify the downside in my mind. It appears minimal.

In my mind, there is potential downside (nerve injury - I believe that data comes from review of the closed claims database), and no upside (I don't need it as a vascular marker, and it doesn't prolong my blocks).
 
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In my mind, there is potential downside (nerve injury - I believe that data comes from review of the closed claims database), and no upside (I don't need it as a vascular marker, and it doesn't prolong my blocks).
I think it's from animal studies that they showed the nerve damage.
 
Epi enhances lido potency and alters distribution within nerve

Weber A, Fournier R, Van Gessel E, Riand N, Gamulin Z: Epinephrine does not prolong the analgesia of 20 mL ropivacaine 0.5% or 0.2% in a femoral three-in-one block. Anesth Analg 2001;93:1327–1331.
Epi does not lengthen duration of ropi

Metaanalysis of 70 trials, epi adds maybe an hour of analgesia at most

Apparently this article shows that bupi 0.5 has minimal effect on nerves as seen under electron microscopy but with epi there's some damage. I can't access this article but another article that references this one says that this is what it shows.

In general I try to keep my anesthetics as simple as I can. I just draw everything up in as few syringes as possible and use the minimum amount of medication. I don't get when people mix prop and etomidate or use sux for a fast intubation when roc alone is fine. If something doesn't help and can possibly hurt, I eliminate it.
 
Do people who use epi in blocks also believe that epi given IM in a code is worthless?
 
Do people who use epi in blocks also believe that epi given IM in a code is worthless?
150 mcg versus 1 mg? Plus it’s diluted into a huge volume in a nerve block that isn’t quickly absorbed. I agree it slowly gets absorbed, but I’ve done lots of nerve blocks with epi in the mix and have never seen a HR change.
 
I have no strong opinion, in a higher vascular area I like epi as an additional intravascular indicator, so I will use it in a supraclavicular or adductor. I think it’s stupid in something like a fem or pop.
 
I’ve always done it for ultrasound ISBs (w/ pulse ox beeping) with the idea of detecting intravascular, but I’ve never seen heart rate jump up. Maybe it’s not worth the time and theoretical risk. I do think aspiration alone is inadequate, need to see local spread. But realistically not sure how many different things one can focus on effectively (aspiration, local spread, heart rate, hot nurse...)
 
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Or the old through and through technique

Slightly different “through and through” but in the olden days we used to do transarterial axillary blocks. We’d deliberately insert the needle into the axillary artery and advance through the backwall until we got negative aspiration and dump half the local there. Then withdrew the needle until we got negative aspiration and dumped the rest of the local in front of the front wall. Epi was useful for those.
 
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