When patient is intubated and spontaneously breathing on manual or minimal PSV how many TOF twitches does that equate to ?

[Pablo94]

This is probably a stupid question, but I cannot find an answer online or in textbooks. My attending made it seem like if a patient is breathing on their own they have at least 2/4 TOF ?

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[Gator7]

not a dumb question, but there really isn’t an answer. Too many other variables besides level of neuromuscular blockade go into the patients ability to spontaneously ventilate. Such as narcotic usage, ETCO2, pulmonary status, how sick the patient is, etc.

Maybe your attending meant that if you see at least 2 peripheral twitches then it’s possible to start seeing diaphragm movement. Like if you see 2 or more twitches in the middle of a robotic case it’s probably a good idea to give some more roc before the da Vinci commits murder

 

[kidthor]

Well you probably have more than zero twitches, but probably nobody really knows the exact number beyond that. Plus how are you registering whether they’re breathing? If you set a vent to PSV with a sensitive flow trigger you often see convincing evidence of breathing that you barely see on manual/spont.

 

[abolt18]

not a dumb question, but there really isn’t an answer. Too many other variables besides level of neuromuscular blockade go into the patients ability to spontaneously ventilate. Such as narcotic usage, ETCO2, pulmonary status, how sick the patient is, etc.

Maybe your attending meant that if you see at least 2 peripheral twitches then it’s possible to start seeing diaphragm movement. Like if you see 2 or more twitches in the middle of a robotic case it’s probably a good idea to give some more roc before the da Vinci commits murder

I think Pablo is asking because if one equates adequate spontaneous ventilation or adequate ventilation on minimal pressure support settings as being 2(or more)/4 twitches, then you can reverse paralytic without checking twitches. My guess anyway.

 

[Pablo94]

Yes they were breathing well on manual. I was just curious if for instance a patient is breathing regularly and pulling good tidal volumes on manual if we can assume that they have for example 1/4 or 2/4 twitches?

 

[NICMAN]

My practice: it is always best to check twitches. I have seen too many people extubated by inexperienced CRNAs who “swear they had 4/4 twitches” when I suspect they were going by strength of man/spont.

 

[Radetzky]

Diaphragm gains function well before other muscles, don’t trust it

 

[teacher2md]

If you set the flow trigger to 0.5 L/min sometimes even cardiac motion will trigger it…

 

[coffeebythelake]

Diaphragm is the most resistant to nmbd and recovers quickly.

 

[PAC2DO]

I usually get at least 2/4, but mostly 3-4. I also set the trigger at 2.5 with 7/5 and usually reverse with 2 mg/kg of sugammadex.

 

[Ronin786]

Don’t trust what any attending says. For your next 10 patients, get them breathing and see how many twitches they have. You’ll be surprised.

 

[BLADEMDA]

https://www.e-safe-anaesthesia.org/sessions/16_03/d/ELFH_Session/601/tab_859.html

1 twitch or zero twitches with post tetanic movement. I think the clinical answer is 1-2 twitches with Sevo running as the agent.

Return of spontaneous ventilation and normal tidal volumes should not be used for timing of pharmacologic reversal as intubated patients often have adequate ventilation despite low TOF counts.

 

[GassYous]

Ive have patients need sugammadex after extubating with good tv on spontaneous ventilation at the end of the case. It is not a reliable measure, just like head lift or whatever

 

[anbuitachi]

Ive have patients need sugammadex after extubating with good tv on spontaneous ventilation at the end of the case. It is not a reliable measure, just like head lift or whatever

ive also seen this when patient has 4/4 twitches. reverse with full dose neo glyc, and still need suggamdex in pacu. i guess thats why they recommend quantitiitaitive tof

 

[nimbus]

ive also seen this when patient has 4/4 twitches. reverse with full dose neo glyc, and still need suggamdex in pacu. i guess thats why they recommend quantitiitaitive tof

I saw this a lot when we weren’t supposed to give sugammadex to dialysis patients. Give full dose neostigmine/glyco—>patient still weak—>give sugammadex—>patient can do push-ups.

 

[itwasalladream]

My practice is to reverse everyone I paralyzed but plan to extubate in the OR. If they're breathing reasonable volumes on PSV 5/5 or 10/5, I'm comfortable that they have something more than 0/4 twitches. But I don't think you can say much more than that. Just reverse them.

 

[PpfSuxTube]

ive also seen this when patient has 4/4 twitches. reverse with full dose neo glyc, and still need suggamdex in pacu. i guess thats why they recommend quantitiitaitive tof

What is full dose neo/glyco?
What was their TOF ratio? Was it reliably increasing over time during the case or just a one off?
What was the dose of roc and the timeframes?
How long pre extubation did you give the neo/glyco?

 

[PpfSuxTube]

A lot of people rag on neo/glyco. I don't care personally. But then can't describe its pharmacology well, or tof ratios either...

Tof ratios, and adequately dosed and timed neo/glyco works very well... sugammadex is obviously better, cleaner but neo glyco does work when paired with right monitor and circumstances, and clinician most importantly

This is probably a stupid question, but I cannot find an answer online or in textbooks. My attending made it seem like if a patient is breathing on their own they have at least 2/4 TOF ?

No one knows i agree with you. Probably 2/4, but it's an almost useless number practically anyway. You can't and shouldnt base a clinical decision on this little info alone

Tof count is not a useful metric. And no, the human eye cannot adequately detect fade or tof ratio

 

[PpfSuxTube]

I am constantly shocked at the number of ORs I work in where the TOF ratio handpiece is gathering dust since the last time I used it in there months before. None of my colleagues use it, which is substandard.
It's fine to say the equipment may be old and faulty, but not ok to not even put it on. It is an essential monitor any time nmbs are used

 

[GassYous]

My practice is to reverse everyone I paralyzed but plan to extubate in the OR. If they're breathing reasonable volumes on PSV 5/5 or 10/5, I'm comfortable that they have something more than 0/4 twitches. But I don't think you can say much more than that. Just reverse them.

If it's been 3 hours or more (long spine case) I don't reverse but otherwise I do

 

[anbuitachi]

I am constantly shocked at the number of ORs I work in where the TOF ratio handpiece is gathering dust since the last time I used it in there months before. None of my colleagues use it, which is substandard.
It's fine to say the equipment may be old and faulty, but not ok to not even put it on. It is an essential monitor any time nmbs are used

most of the ORs i work dont have quantitative monitoring. Some dont even have TOF. I carry my own hand held zapper and use my eyes.

 

[anbuitachi]

What is full dose neo/glyco?
What was their TOF ratio? Was it reliably increasing over time during the case or just a one off?
What was the dose of roc and the timeframes?
How long pre extubation did you give the neo/glyco?

dont know. not my cases. i was covering pacu and was the one who gave suggamadex every time. all i remember now is they gave around 4mg of neo, and patient is avg height/size

 

[PpfSuxTube]

most of the ORs i work dont have quantitative monitoring. Some dont even have TOF. I carry my own hand held zapper and use my eyes.

View attachment 377635

That's a Shame...
Correct me if I'm wrong but I don't think there's much evidence for these in terms of extubation.
IIRC they can give you a count but not anything accurate to say tof ratio is > 0.9

Even at 0.8 there is clinically significant residual weakness seen in pacu.

No way anyone's eye can tell between 0.8 and 0.9... I doubt eyeballing can even tell the difference between 0.5 and 0.9

The dose of neo is 30 to 70 mcg per kilo, depending on many other factors also, so they may easily have been under dosed... well done to you on helping your patients

 

[Ronin786]

Max dosage of neostigmine is supposed to be 5mg. For the "avg" 100kg patient nowadays does anybody end up using more? Never understood the max dosage part.

We have suggamadex available so I just use that whenever.

 

[GassYous]

Max dosage of neostigmine is supposed to be 5mg. For the "avg" 100kg patient nowadays does anybody end up using more? Never understood the max dosage part.

We have suggamadex available so I just use that whenever.

Max dosage is because if you use more there's too much acetylcholine and there's overstimulation of the muscarinic receptor a la cholinergic crisis. Not sure if anyone has actually seen it happen but I'm sure it does. I was also taught in residency never to give neostigmine alone to avoid life threatening bradycardia and asystole but I'm not sure that this happens either. I have given neostigmine alone in ogilvies syndrome and the patient didn't die

 

[nimbus]

Max dosage is because if you use more there's too much acetylcholine and there's overstimulation of the muscarinic receptor a la cholinergic crisis. Not sure if anyone has actually seen it happen but I'm sure it does. I was also taught in residency never to give neostigmine alone to avoid life threatening bradycardia and asystole but I'm not sure that this happens either. I have given neostigmine alone in ogilvies syndrome and the patient didn't die

Did they code brown or just fart?

 

[abolt18]

Max dosage is because if you use more there's too much acetylcholine and there's overstimulation of the muscarinic receptor a la cholinergic crisis. Not sure if anyone has actually seen it happen but I'm sure it does. I was also taught in residency never to give neostigmine alone to avoid life threatening bradycardia and asystole but I'm not sure that this happens either. I have given neostigmine alone in ogilvies syndrome and the patient didn't die

Stories of more than one patient coding in the ICU after neostigmine for Ogilvie syndrome where I did residency.

 

[PpfSuxTube]

Did they code brown or just fart?

I saw this one time when it was my 1st week in hospital as a medical student, maybe even 1st day. Never heard of Ogilvies or neostigmine or any of that...

All I remember was this fat fellow farting his bare arse off, Splattering chunks everywhere while 2 surgeons high fived in the background...

 

[jwk]

I was also taught in residency never to give neostigmine alone to avoid life threatening bradycardia and asystole but I'm not sure that this happens either.

I can attest to the fact that it does indeed happen.

Very old school - like 70s - I saw neostigmine or pyridostigmine used to attempt to break PAT/SVT in the ER.

 

[PpfSuxTube]

I can attest to the fact that it does indeed happen.

Very old school - like 70s - I saw neostigmine or pyridostigmine used to attempt to break PAT/SVT in the ER.

You mean in the 1970s you saw this? Wow

 

[GassYous]

I can attest to the fact that it does indeed happen.

Very old school - like 70s - I saw neostigmine or pyridostigmine used to attempt to break PAT/SVT in the ER.

I guess the patient wasn't the only one sh!!tting their pants

 

[Ronin786]

Max dosage is because if you use more there's too much acetylcholine and there's overstimulation of the muscarinic receptor a la cholinergic crisis. Not sure if anyone has actually seen it happen but I'm sure it does. I was also taught in residency never to give neostigmine alone to avoid life threatening bradycardia and asystole but I'm not sure that this happens either. I have given neostigmine alone in ogilvies syndrome and the patient didn't die

But that's why you're adding the equivalent dosage of anti-muscarinic agent. I just don't understand weight based dosing with a max.

 

[GassYous]

But that's why you're adding the equivalent dosage of anti-muscarinic agent. I just don't understand weight based dosing with a max.

That's a great question! Why don't you look it up and present it on rounds tomorrow morning.

Perhaps you can only inhibit acetylcholinerestase so much and giving more doesn't help