Neo/Glyco: To mix or not to mix...that is the question

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Femtochemistry

Skunk Works
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Hello guys;

CA-2 here. So I see a lot of CRNA/SRNAs mix their neo/glyco. I was taught early on in residency this is "dumb" as you can not "titrate" your dose. About a few months ago, I ran into an attending (CCM-Anes) that actually prefers to mix the two. Although, he really didn't explain why he liked to do so. I have experimented w/ mixing the two (w/ attending approval of course) and I can't say I have noticed anything groundbreaking here. I actually like two separate syringes. I feel I have better control over how much I am giving. Any thoughts from SDN attendings?


Cheers!

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What do you mean by "better control"? Yu are the one that would be doing the mixing, right?

I prefer to mix.
 
What do you mean by "better control"? Yu are the one that would be doing the mixing, right?

I prefer to mix.

By control I mean I know EXACTLY how much I am giving if I am pushing two separate syringes, not some arbitrary ratio in a mixed syringe.
 
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By control I mean I know EXACTLY how much I am giving if I am pushing two separate syringes, not some arbitrary ratio in a mixed syringe.

Ok, but you are still the one that mixed the meds so don't you know exactly what you are giving?

I draw up 2cc glyco and then I add 2cc neo. I know exactly what I am giving. If I want more neo then I draw up more. It doesn't change once it's in the syringe.

I'm trying to figure out why people don't mix the two. I understand in peds but honestly I mix there as well.
 
What I see here is 5mg of Neo (1mg/cc) and .6mg (.2/cc) of glyc in a 10cc syringe; most if not all of the time they just give the whole damn thing. Which I think is over-kill.

From my little experience in anesthesia, I try to give as much or as little it would take to bring back 4 twitches, spont breathing, good TV, etc etc. These drugs are not benign! I don't understand why we consistenly give 5mg of neo and .6 or more of glyco? I can't get the concept in my head of mixing these drugs.
 
What I see here is 5mg of Neo (1mg/cc) and .6mg (.2/cc) of glyc in a 10cc syringe; most if not all of the time they just give the whole damn thing. Which I think is over-kill.

From my little experience in anesthesia, I try to give as much or as little it would take to bring back 4 twitches, spont breathing, good TV, etc etc. These drugs are not benign! I don't understand why we consistenly give 5mg of neo and .6 or more of glyco? I can't get the concept in my head of mixing these drugs.

You are right to question this "cookbook anesthesia", in my opinion. The ratio of neo to glyco should be closer to 1mg:0.2mg. If your syringe was mixed as such, titrating would be much easier. I give a max dose of neo 0.07mg/kg, and dose according to how much reversal I think the pt needs.
 
I'm a mixer. Usually 5 and 0.8. I titrate the amount to twitches.

I even mix my end of case antiemetics, if I'm using metoclopramide and ondansetron.

On induction out here I've been mixing lidocaine with dexamethasone (used for antiemtic prophylaxis)

I had one attending in residency who would mix all of his cardiac induction meds. Get a 60 ml syringe, put your 1 mcg/kg of fentanyl, etomidate, and pancuronium in it. Inject slowly following preoxygenation, prepare to mask ventilate for a bit. It was actually pretty nice. Made for a very smooth induction. No syringe shuffling either.

Some people are lumpers, some are splitters. I'm a lumper.
 
there is some data that suggests that giving more than 3mg of neostigmine can cause paradoxical muscle weakness/recurarization. i never give more than 0.6/3, and I dont mix it but i dont necessarily wait for anything to happen either. mainly the reason not to mix is so you can have the glyco drawn up already for intraop bradycardia.

i also saw my first example of presumed neostigmine induced bradycardia the other day as well, so im not sure how prevalent it is.
 
I mix it... just easier. My goal for the case is to use 1 20cc syringe and one 10cc syringe (unless doing a heart or something of the like). Glyco works faster than neo, so I ask... WHY do you need to give it seperately?

If you are doing a pedi case and want some glyco drawn up I understand, but for adult cases... I don't have it drawn up.

I often (sometimes not depending on circumstances of the patient) mix prop, roc, decadron and lido in one syringe. Draw it up as the patient is getting their monitors on. Give it all at induction and save myself a couple of syringes and time. + I have a neat looking workspace.

I do believe that dexa and zofran precipitate. So, I don't mix these two + I give zofran about 15 minutes before emergence.
 
Hello guys;

CA-2 here. So I see a lot of CRNA/SRNAs mix their neo/glyco. I was taught early on in residency this is "dumb" as you can not "titrate" your dose. About a few months ago, I ran into an attending (CCM-Anes) that actually prefers to mix the two. Although, he really didn't explain why he liked to do so. I have experimented w/ mixing the two (w/ attending approval of course) and I can't say I have noticed anything groundbreaking here. I actually like two separate syringes. I feel I have better control over how much I am giving. Any thoughts from SDN attendings?


Cheers!

I'm afraid your attendings do not mix just to feel superior to the "dumb nurses who mix". The titration story seem BS to me. I guess you could give the neo, make them bradycardic then titrate the glyco in. But, is that safe? Safer then the pt getting tachycardic for a minute or two? Are you sure? Cosidering that in the meantime of your shenanigans the pt has a big bowel movement on the bed thanks to your great anesthetic prowess. Great! Now there is **** in a sterile environment!
 
Here's my approach:
I use the formula neo 0.07mg/kg and glyco 0.007mg/ kg as a max. If my pt is somewhat tachy or I really don't want any tachycardia with emergence then I cut the ratio down to 0.07 and 0.004ish. I count on some of the neo to decrease the HR. I usually give 1/2 this dose if I am reversing but like I said I don't always reverse.

If they are Brady then I go the other way more glyco and less neo.

It's not rocket science but it is medicine and I use the SE's to my advantage when I can.
 
Cosidering that in the meantime of your shenanigans the pt has a big bowel movement on the bed thanks to your great anesthetic prowess. Great! Now there is **** in a sterile environment!

:laugh::laugh:

Dang Straight!
 
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I've had attendings tell me that they like it mixed so that there isn't anyway that you could accidentally give the neo and get busy doing something else forget to follow it up with the glyco.
 
I've had attendings tell me that they like it mixed so that there isn't anyway that you could accidentally give the neo and get busy doing something else forget to follow it up with the glyco.

If you're giving them separately, it should always be glyco first anyway...
 
Here's my approach:
I use the formula neo 0.07mg/kg and glyco 0.007mg/ kg as a max. If my pt is somewhat tachy or I really don't want any tachycardia with emergence then I cut the ratio down to 0.07 and 0.004ish. I count on some of the neo to decrease the HR. I usually give 1/2 this dose if I am reversing but like I said I don't always reverse.

If they are Brady then I go the other way more glyco and less neo.

It's not rocket science but it is medicine and I use the SE's to my advantage when I can.

20-30 mg esmolol is very effective at treating post-reversal tachycardia, otherwise its fairly self-limiting.

ive always viewed the anticholinergic as protective rather than as a treatment for neostigmine induced bradycardia, which may be refractory to glyco given after the heart rate has changed (thus, why you should give it first).

i also disagree with letting your heart rate determine your reversal plan, since that assumes you can accurately predict the response. i think you have to be ready with esmolol and atropine handy (not drawn up) in case you get extreme tachy in a patient with tight coronaries or unexpected bradycardia even with appropiate dosing, but if you are lowering your dose of neo based on preexisting bradycardia, then I think you can get into trouble.

but this is just my opinion, i dont have anything but anec-data to support it.
 
You are right to question this "cookbook anesthesia", in my opinion. The ratio of neo to glyco should be closer to 1mg:0.2mg. If your syringe was mixed as such, titrating would be much easier. I give a max dose of neo 0.07mg/kg, and dose according to how much reversal I think the pt needs.

The 1neo:0.2glyco has always seemed like overkill to me and I abandoned it a long time ago - too many tachycardias. My usual mix is 3 and 0.4. As long as you know what you have, if you want to titrate the dose it's really not rocket science to figure out what you gave.

I used to give 5 of neostigmine to just about everyone, but I was also raised in the days of pancuronium and DTC, so my background is warped. ;)
 
Ours are already premixed so no choice there: glycopyrronium, bromure 0,5mg + néostigmine, méthylsulfate 2,5mg / 1ml
 
20-30 mg esmolol is very effective at treating post-reversal tachycardia, otherwise its fairly self-limiting.

ive always viewed the anticholinergic as protective rather than as a treatment for neostigmine induced bradycardia, which may be refractory to glyco given after the heart rate has changed (thus, why you should give it first).

i also disagree with letting your heart rate determine your reversal plan, since that assumes you can accurately predict the response. i think you have to be ready with esmolol and atropine handy (not drawn up) in case you get extreme tachy in a patient with tight coronaries or unexpected bradycardia even with appropiate dosing, but if you are lowering your dose of neo based on preexisting bradycardia, then I think you can get into trouble.

but this is just my opinion, i dont have anything but anec-data to support it.

your missing the point. I don't need the esmolol because I don't give a dose that will cause tachycardia. And yes we give the glyco to prevent the bradycardia from neo.

Where did I say I was letting HR determine my reversal dose? If you read carefully, the neo dose remains the same at 0.07 and its the glyco that is decreased. You do know that the neo is the reversal agent, don't you?

Now if you don't mind, Im gonna wake my pt up without reversal.:eek:
 
I mix it... just easier. My goal for the case is to use 1 20cc syringe and one 10cc syringe (unless doing a heart or something of the like). Glyco works faster than neo, so I ask... WHY do you need to give it seperately?

If you are doing a pedi case and want some glyco drawn up I understand, but for adult cases... I don't have it drawn up.

I often (sometimes not depending on circumstances of the patient) mix prop, roc, decadron and lido in one syringe. Draw it up as the patient is getting their monitors on. Give it all at induction and save myself a couple of syringes and time. + I have a neat looking workspace.

I do believe that dexa and zofran precipitate. So, I don't mix these two + I give zofran about 15 minutes before emergence.

then mix in a little methylene blue for some pizazz
 
Here's my approach:
I use the formula neo 0.07mg/kg and glyco 0.007mg/ kg as a max. If my pt is somewhat tachy or I really don't want any tachycardia with emergence then I cut the ratio down to 0.07 and 0.004ish. I count on some of the neo to decrease the HR. I usually give 1/2 this dose if I am reversing but like I said I don't always reverse.

If they are Brady then I go the other way more glyco and less neo.

It's not rocket science but it is medicine and I use the SE's to my advantage when I can.

I had a question about that as well.. Right there you say if they're brady you give less neo... but I am sure this is a type-o since you just said it yourself you shouldn't give less neo, because it's the reversal agent, giving less neo would mean possibly not reversing all the way.
 
Ohh and I am a mixer, every place i rotated and the place i am now training mixes.. We use 5mg Neo and 1mg of Glyco, in fact they used the same ratio at the three places i rotated as a med student as well.

During our first week of anesthesia rotation, one of my classmates gave a stick of just neo cause he didn't know that they wanted him to mix and no one specified, they just gave him a bunch of vials and said draw this up, then they took a syringe from him without asking what it was and pushed it. The pt bradied down to the low 40's before they realized what happened and gave glyco. After that we all got an email saying we should mix the two.
 
You are right to question this "cookbook anesthesia", in my opinion. The ratio of neo to glyco should be closer to 1mg:0.2mg. If your syringe was mixed as such, titrating would be much easier. I give a max dose of neo 0.07mg/kg, and dose according to how much reversal I think the pt needs.

This is the ratio I give.
 
there is some data that suggests that giving more than 3mg of neostigmine can cause paradoxical muscle weakness/recurarization. i never give more than 0.6/3, and I dont mix it but i dont necessarily wait for anything to happen either. mainly the reason not to mix is so you can have the glyco drawn up already for intraop bradycardia.

i also saw my first example of presumed neostigmine induced bradycardia the other day as well, so im not sure how prevalent it is.

Even in my n=6 weeks, the bolded is not a terrible reason to keep them separate. Had a pretty young healthy female brady down to <30 after insufflation, was wishing I had the glyco already drawn up.
 
Where did I say I was letting HR determine my reversal dose? If you read carefully, the neo dose remains the same at 0.07 and its the glyco that is decreased. You do know that the neo is the reversal agent, don't you?

i dont know where i read that...

Here's my approach:
I use the formula neo 0.07mg/kg and glyco 0.007mg/ kg as a max. If my pt is somewhat tachy or I really don't want any tachycardia with emergence then I cut the ratio down to 0.07 and 0.004ish. I count on some of the neo to decrease the HR. I usually give 1/2 this dose if I am reversing but like I said I don't always reverse.

If they are Brady then I go the other way more glyco and less neo.

It's not rocket science but it is medicine and I use the SE's to my advantage when I can.

oh thats right. no need to get smart with me. i cant anticipate your typographical errors or misstatements.
 
I don't mix. I couldn't care less if I use 2 5 cc syringes vs 1 10 cc. I usually give 0.2mg less of glyco than I'm "supposed" to, but also like to fractionate the dosing. The patient population I have been taking care of have a very high incidence of PAD and CAD. I have nothing to gain by getting them tachycardic. Esmolol's a great drug but why even get to the point of needing it?
 
I don't mix. I couldn't care less if I use 2 5 cc syringes vs 1 10 cc. I usually give 0.2mg less of glyco than I'm "supposed" to, but also like to fractionate the dosing. The patient population I have been taking care of have a very high incidence of PAD and CAD. I have nothing to gain by getting them tachycardic. Esmolol's a great drug but why even get to the point of needing it?

Agreed.

I mix however. I always use one less cc of glyco than neo. I like the idea that people say on this forum however of using a full dose.

I think i'll start doing that.

One attending at my place does 5cc's neo, 3cc's glyco. It works well for him. I tried it once and the guy got too brady for my taste, now I do 5/3.5, or 5/4.
They get tachy from emerging anyway, why not use the properties of the neo to our advantage.
 
We recently had a death from inadequate glyco dose (0.6mg for 5mg neostigmine). Unrecognized CAD in a patient with conduction defects. I won't do 0.4 less, but 0.2 less seems fine.
 
to the OP. You can probably tell by the flury of responses in such a short time that there is a lot of sciene and art to the concept and administration of reversal.

I'll throw in my 2 cents.

Know what the drugs are that you're giving and understand their pharmacokinetics and dynamics. If you wanna mix these two: it's not a problem, but like any drug; know your patient and what the drugs may do to them. Their pathophys may encourage you to change your ratio a bit case by case, or even split them. to minimize/change the effect profiles.

My recommendation to more junior residents is to split them (if your attendings don't mind).
This is simply to remind you about the dosing and drill into your memory how to calculate it.

The concentrations of glyco and neo vary sometimes hospital to hospital (and hugely internationally) so getting used to mixing 1ml to 1ml leaves you lost if you're suddenly somewhere that has different concentrations (it may even be dangerous if you don't recognize that the concentration is different because you're not used to looking at the dose).

Splitting them, in the beginning, can also give you more familiarity with the drugs and help you get a feel for them if you end up using them in alternate uses (besides "reversing" someone).

If you want to know what I do: I split mine, but it's because I've worked at a lot of different hospitals and also teach a lot, so I am a bit more OCD about really watching what I draw up, and that way I don't question whether my trainee may have mixed the two together properly.
 
to the OP. You can probably tell by the flury of responses in such a short time that there is a lot of sciene and art to the concept and administration of reversal.

I'll throw in my 2 cents.

Know what the drugs are that you're giving and understand their pharmacokinetics and dynamics. If you wanna mix these two: it's not a problem, but like any drug; know your patient and what the drugs may do to them. Their pathophys may encourage you to change your ratio a bit case by case, or even split them. to minimize/change the effect profiles.

My recommendation to more junior residents is to split them (if your attendings don't mind).
This is simply to remind you about the dosing and drill into your memory how to calculate it.

The concentrations of glyco and neo vary sometimes hospital to hospital (and hugely internationally) so getting used to mixing 1ml to 1ml leaves you lost if you're suddenly somewhere that has different concentrations (it may even be dangerous if you don't recognize that the concentration is different because you're not used to looking at the dose).

Splitting them, in the beginning, can also give you more familiarity with the drugs and help you get a feel for them if you end up using them in alternate uses (besides "reversing" someone).

If you want to know what I do: I split mine, but it's because I've worked at a lot of different hospitals and also teach a lot, so I am a bit more OCD about really watching what I draw up, and that way I don't question whether my trainee may have mixed the two together properly.

:thumbup:
 
Hello guys;

CA-2 here. So I see a lot of CRNA/SRNAs mix their neo/glyco. I was taught early on in residency this is "dumb" as you can not "titrate" your dose. About a few months ago, I ran into an attending (CCM-Anes) that actually prefers to mix the two. Although, he really didn't explain why he liked to do so. I have experimented w/ mixing the two (w/ attending approval of course) and I can't say I have noticed anything groundbreaking here. I actually like two separate syringes. I feel I have better control over how much I am giving. Any thoughts from SDN attendings?


Cheers!

All kidding aside,

This thread has taken off which surprises me since if I could pick a list of

The Top Ten Anesthesia Dogmas

this

conversation

"Uhhhhhhhhhhhhhhhhh, is it better to keep the neo and glyco separate or should I combine them

would be in the top ten.

Y'all can continue to

mentally masturbate

about this issue.

Great!

wait for it.....wait for it....

It doesn't matter.

This is where academia pisses me off.

Implanting

DOGMAS

in residents minds

then the resident becomes an academic attending

then the academic attending propagates the DOGMA

to residents


and so on and so on

I know this business.

There is NO WAY to calculate an appropriate reversal dose. You can kid yourself that, ohhhhh....

I'VE GOT A

TWITCH MONITOR

that "scientifically" figures it out!!!!!


HAHAHAHAHAHAHAHAHAHAHAHA !!!!!

No man.

The twitch monitor can

guide you.

That's about it.

Looking for how to

REALLY KNOW


about reversal?

I posted a link to a thread that occurred four years ago.

Review my posts on that thread.

Post #27.

That's

how you handle reversal.

The academics can continue to try to make it look like it,

but

IT AIN'T ROCKET SCIENCE.

And propagating it as

ROCKET SCIENCE

leads to the posts on this thread from

"titrating scientists"

depicted on posts above.
 
Last edited:
I was taught early on in residency this is "dumb" as you can not "titrate" your dose.

Um...what drug are you titrating to which effect?

Neostigmine to adequate reversal of neuromuscular blockade, e.g. TOF > 0.9? (Something no human can do, btw)

Or glycopyrrolate to appropriate HR? You def don't need to do this. Put 5mg neostigmine with 0.6-0.8mg of glycopyrrolate and give however much you think the patient needs based on their starting HR. Young people can jack their HR with a 5/0.6 ratio. But that might also make them s**t their pants.
 
1) Patient breathing well on own at end of case? Havent dosed NMB in quite a while? Belly's empty? And if it wasnt empty to begin with, didja put down an OGT and suck it out? You apply twitch monitor and the left side of their face cringes like A-Rod looking at his picture in the newspaper with the hot (non wife) blondie?

Extubate. 99.99% of the time theres no problem.

Will you see somebody weak on occasion? Yep. You'll see this even after reversal on some patients. But isnt that why we monitor patients?

You are The Wolf. You solve problems. Thats what youre there for. Thats why we monitor people in the PACU.

So they're a little weak, but holding their sat. 99% of these people you give versed 2mg to so they wont remember the next twenty minutes.

Reintubation of a weak patient is very rare. Yes, it happens....in both reversed patients and non-reversed patients.


2) TWITCH MONITOR INTERPRETATION:

Theres three choices.

Its either 1)REALLY STRONG.....2)TWITCHES ARE BACK BUT KINDA WEAK.......or.....3)I FEEL LIKE STEVIE WONDER LOOKING AT THESE TWITCHES.

Wanna reverse everyone with REALLY STRONG twitches who is breathing well? I wont argue with you. I don't.

TWITCHES ARE BACK BUT KINDA WEAK: Give full reversal. Don't taylor the reversal. Give it all.

STEVIE WONDER TWITCHES: You just bought yourself twenty minutes of wasted time. Once you see a good twitch, reverese with full reversal...butcha may need to T-piece-em to the PACU. If you do, give midazolam 2mg so they wont remember.

There ya have it.

Jet's VERY SCIENTIFIC GUIDE TO TWITCH MONITOR UTILIZATION.

okay so, reverse some people, dont reverse others, and give versed to the weak ones? i mean just so we have the holy word as handed down and not through some dogmatic interpretation...
 
For all I might think or post about this issue, what Jet is describing is exactly what I end up doing and how I end up feeling about the issue in day to day, MD only practice.

- pod
 
after reading this post noticed that my 5/1mg neo/glyco dose was causing tachycardia in most pt's, so today i dropped the ratio to 5/0.8mg neo/glyco and it works like a charm.
 
after reading this post noticed that my 5/1mg neo/glyco dose was causing tachycardia in most pt's, so today i dropped the ratio to 5/0.8mg neo/glyco and it works like a charm.

Isn't it cool when you read something here and it works.
 
Yes I usually give .8/5 to the weak ones, and .5/3 to the other ones. No tachycardia usually. You guys were right on the roc, I cut back to 5-10mg for redosing. Definitely saved my bacon in a few cases where my former dosing would have screwed me. Took over a case for another resident this AM just after he redoses with 20mg. Got my first twitch back an hour later, 10 minutes before closing. Reviewing AKT keywords with another resident this afternoon, and on about 4 times I caught myself saying "According to what I've read on SDN". This board is by far the best attending I have.
 
Yes I usually give .8/5 to the weak ones, and .5/3 to the other ones. No tachycardia usually. You guys were right on the roc, I cut back to 5-10mg for redosing. Definitely saved my bacon in a few cases where my former dosing would have screwed me. Took over a case for another resident this AM just after he redoses with 20mg. Got my first twitch back an hour later, 10 minutes before closing. Reviewing AKT keywords with another resident this afternoon, and on about 4 times I caught myself saying "According to what I've read on SDN". This board is by far the best attending I have.


And these attendings are here everyday, not just 2-3 days a week and out the door at 2 pm on work days.
 
And these attendings are here everyday, not just 2-3 days a week and out the door at 2 pm on work days.

It's great after residency, too. I'm 2 years out now, and this board is more useful than any of the CME I slog through for MOCA and license renewal.

The quality of the discussions here, even with the off-topic threads and occasional drama, is far better than what I get face-to-face every day.
 
A lot of these "attendings" (no such word in private practice), were med students and residents on this board. Nice to keep on learning/hearing others perspective and give back when you can. Full circle. :)
 
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