Checking twitches

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narcusprince

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With suggamadex dosing at 4mg/kg with 0 twitches does it make sense to check twitches anymore versus just giving the suggamadex? If my patient has spontaneous effort on thw vent I give 2mg/kg. We all know the academic answer what are you guys practicing?
 
With suggamadex dosing at 4mg/kg with 0 twitches does it make sense to check twitches anymore versus just giving the suggamadex? If my patient has spontaneous effort on thw vent I give 2mg/kg. We all know the academic answer what are you guys practicing?

If you have suggamadex readily available to use then no, i dont think there is much use to checking twitches. the problem is it interferes with birth control so you have to explain that to patients which is annoying.
we dont have suggamadex readily available here cause it's a little bit more expensive so still using glyc/neo.
 
4 mg/kg if they have 0 twitches but still have 1-2 post tetanic. Otherwise it's 16 mg/kg from my understanding.

I've tried it out a few times and don't really see much difference between 2 mg/kg vs 4 mg/kg. The drug is magic. Also I believe that the 500 mg bottle is cheaper than two of the 200s.
 
I was told by one attending for cya purposes you need to document tetanus no fade post reversal. Shes a bit batty, but I end up doing it because it takes an extra second.
 
With suggamadex dosing at 4mg/kg with 0 twitches does it make sense to check twitches anymore versus just giving the suggamadex? If my patient has spontaneous effort on thw vent I give 2mg/kg. We all know the academic answer what are you guys practicing?

It's a good point of discussion - does sugammadex make TOF (or twitches in general) obsolete?

I would argue that with spontaneous effort on the vent you *could* still have 0-1 twitches and 4/kg reversal would be indicated. With "more" recovery (>2-4/kg TV) I think reasonable to just give 2/kg.

In practice, ahem, patients are usually getting either 200mg or 400mg. (because we have 200mg vials)

I don't know you'd ever see any residual weakness if you're giving 4/kg sugammadex to everyone who can show any muscular effort whatsoever.

It's a wonderful drug. Our dept spends a lot on it currently.
 
In my practice if you have spontanous effort on the vent you have 1 twitch. 2mg/kg is indicated. I would argue you that patients whom are higher risk of pulmonary complications severe osa, morbidly obese, shunt(pnemonia pul edema) you should give the 4mg/kg dose.
 
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In my practice if you have spontanous effort on the vent you have 4 twitches. 2mg/kg is indicated. I would argue you that patients whom are higher risk of pulmonary complications severe osa, morbidly obese, shunt(pnemonia pul edema) you should give the 4mg/kg dose.

That's not how it works
 
If someone is breathing spontaneously with negative pressure ventilation with you have to have at least one twitch. Meaning you can reverse with 2mg/kg. With 0 twitches but post tetatanic twitches you reverse with 4mg/kg. Spontaneous effort = at least 1 twitch.
 
In someone with at least 1 twitch with compromised pulmonary function I would reverse with 4mg/kg. I want to make sure all the roc is bound especially in those patients whom would be more succeptable to fail extubation.
 
Residual blockade remains as high as 9.4% after sugammadex if given blind... according to this one study.

"The attending anesthesiologists administered 2 mg/kg sugammadex at the conclusion of surgery if bucking against the tracheal tube, spontaneous breathing, or movement of extremities were noted. If these signs were not present, 4 mg/kg sugammadex was administered IV."

Reversal with Sugammadex in the Absence of Monitoring Did... : Anesthesia & Analgesia
 
Honestly... after too many years in this business... I think that twitch monitors are useless. If you think you need to reverse the muscle relaxant then please reverse it, then re assess the patient clinically, and extubate when you feel it's clinically appropriate.
the best monitor is YOU, you the consultant anesthesiologist should be able to tell when your patient is ready to be extubated.
 
Honestly... after too many years in this business... I think that twitch monitors are useless. If you think you need to reverse the muscle relaxant then please reverse it, then re assess the patient clinically, and extubate when you feel it's clinically appropriate.
the best monitor is YOU, you the consultant anesthesiologist should be able to tell when your patient is ready to be extubated.
I'm new and inexperienced, but all the data says the following:

RNMB cannot be accurately estimated with clinical signs alone (11-14% sensitivity to detect residual blockade (TOF < 0.9))
RNMB estimated between 20-40% on entering PACU when audited/researched with quantitative monitors.
Anaesthetists grossly underestimate the incidence of RNMB (<1% for clinically sig. <5% measurable with quantitative measuring, but not clinically sig).
 
I'm new and inexperienced, but all the data says the following:

RNMB cannot be accurately estimated with clinical signs alone (11-14% sensitivity to detect residual blockade (TOF < 0.9))
RNMB estimated between 20-40% on entering PACU when audited/researched with quantitative monitors.
Anaesthetists grossly underestimate the incidence of RNMB (<1% for clinically sig. <5% measurable with quantitative measuring, but not clinically sig).
Unfortunately medicine is not an exact science and humans don't really behave like motors or machines where a certain change would produce predictable and measurable effects.
They will try to teach you formulas and equations that are supposed to help you know how the human organism behaves, and you will have to learn these awful things in order to pass your exams.
But... eventually... you will realize that it's all BS, and that the only rule that works is your clinical judgement. You see... medicine is not a digital science, it's rather an analog convoluted world... very similar to a complex musical masterpiece or an elaborate work of art, it cannot be fully digitized.
Be curious and be inquisitive but also be humble my friend.
 
I agree with plank. Also I've noticed that there are many times when there are zero twitches but the muscles have started to react a lot stronger to bovie in the field. I rarely rely on the twitch monitor if I can help it.
 
When I first started using sugammadex I would check twitches before and after administration just to learn how it works. In my experience, even densely paralyzed patients with 0/4 twitches become very strong with zero fade on TOF after a 2mg/kg dose. My current practice is to give a 200mg vial and not check twitches. I suppose if I encountered a patient who looked weak after a 200mg dose, I would just give more. That has not happened yet. Residual weakness is no longer an issue in our PACU. It seems to me the recommended doses are higher than necessary.
 
Honestly... after too many years in this business... I think that twitch monitors are useless. If you think you need to reverse the muscle relaxant then please reverse it, then re assess the patient clinically, and extubate when you feel it's clinically appropriate.
the best monitor is YOU, you the consultant anesthesiologist should be able to tell when your patient is ready to be extubated.

The consultant anesthesiologist knows that appearances are not sufficient to judge the degree of residual neuromuscular blockade in a patient. That's both my board answer and my real world answer. I've seen patients meet all the "clinical criteria" for extubation and still not be fully reversed. The thing is if we pull the tube we just don't sit around and watch them every second for very long afterwards so we don't notice the potential problems like microaspiration that lead to increased morbidity in a large number of patients postoperatively.

Just because a patient didn't get reintubated 15 minutes later in PACU doesn't mean they were necessarily free and clear from a complication.
 
The consultant anesthesiologist knows that appearances are not sufficient to judge the degree of residual neuromuscular blockade in a patient. That's both my board answer and my real world answer. I've seen patients meet all the "clinical criteria" for extubation and still not be fully reversed. The thing is if we pull the tube we just don't sit around and watch them every second for very long afterwards so we don't notice the potential problems like microaspiration that lead to increased morbidity in a large number of patients postoperatively.

Just because a patient didn't get reintubated 15 minutes later in PACU doesn't mean they were necessarily free and clear from a complication.
Are you saying that the twitch monitor should be you primary tool to determine full reversal? Or are you just disagreeing with the value of clinical judgement in making that decision?
 
I think suggamadex makes all the talk of twitch monitors and residual weakness points of academia, and irrelevant for everyday practice. Like @nimbus I believe the recommended doses are much higher than needed. My experience has been that I've never needed > 200mg. If I RSI'd with roc and couldn't intubate or ventilate of course I'd give more but I've never needed to do that.
 
For what it’s worth, it takes 3.57mg if suganmadex to bind 1mg of rocuronium. Therefore, if you’re not after “rapid” reversal and you’ve given less than 57mg of rocuronium during a case, you should only ever need the 2ml as far as I can tell.
 
Are you saying that the twitch monitor should be you primary tool to determine full reversal? Or are you just disagreeing with the value of clinical judgement in making that decision?

Quantitative TOF monitoring is the best measure of NMB
 
So if you have full 4 twitches that's all you need to pull the tube out? in all patients?
Can't you have 4 twitches and still have considerable muscle paralysis?
No qualitative measure can reliably predict TOFR >0.7

TOF unable to differentiate >0.4
DBS unable to differentiate >0.6
Tetanic unable to differentiate >0.7

Even with tetanic you still get an area of blind paralysis at TOFR > 0.7.

That's why quantitative tools are recommended as they are the only objective measurement that can adequately assess for residual paralysis in a patient who clinically will appear adequately reversed.
 
Even if a patient has a TOF = 4 without subjective fade, I still reverse with something because studies show we aren't reliable for detecting fade ratios greater than 0.4, increased microaspiration complication rates happen below full reversal (0.9), and clinical signs are very insufficient for detecting full reversal. Just because your patients seem to do fine and don't need to be reintubated doesn't mean you're providing them the best care. Clinical judgment is great, but it should be rooted in evidence when possible. Our anecdotal evidence of how it seems our patients do aren't very good at differentiating a 5% incidence of complication from a 10% incidence.

Personally, I put a lot of stock in ulnar twitch monitors but not so much if they're facial. OO and CS muscles exhibit different resistance to NM blockade. There's a risk of directly stimulating the eye muscles if a person's face doesn't have much room for them. If you put them behind the ear, you sometimes directly stimulate the masseter muscle which makes it harder to detect weak eye muscle twitches. There are just too many problems with it usually.
 
So, is everyone using quantitative TOF monitors these days?

Not unless I’ve given a dose of NMB within a short time of extubation. Although admittedly I don’t do many surgeries where the surgeons are uptight about muscle relaxation and even if, I’m gentle with my relaxant and I reverse just about everyone

Edit: I reverse everyone with Neostigmine and Glyco.
 
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I have never used quantitative tof except at the ivory tower institution. I reverse everyone with at least 200 mg of sugg. If they have recieved roc.

In addition, I have noticed a sharp decline in emergence delirium after the inception of sugg into practice. My belief is neostigmine and glyco are both drugs that can cross the bbb contrary to what the literature says. I rarely have any ED anymore in my practice.
 
I have never used quantitative tof except at the ivory tower institution. I reverse everyone with at least 200 mg of sugg. If they have recieved roc.

In addition, I have noticed a sharp decline in emergence delirium after the inception of sugg into practice. My belief is neostigmine and glyco are both drugs that can cross the bbb contrary to what the literature says. I rarely have any ED anymore in my practice.
I don't even think it's BBB. I've had patients jump off the table with 0.2-0.3 MAC after sugammadex reversal vs sitting like slugs with neo/glyco. I personally believe that a lot of the residual effects of GA that we routinely attribute to gas lingering is in fact sub-clinical neuromuscular blockade. My personal theory is that sugammadex leads to sharper patients post-anesthesia.

I'd actually be interested in any data comparing PACU discharge time.
 
I have never used quantitative tof except at the ivory tower institution. I reverse everyone with at least 200 mg of sugg. If they have recieved roc.

In addition, I have noticed a sharp decline in emergence delirium after the inception of sugg into practice. My belief is neostigmine and glyco are both drugs that can cross the bbb contrary to what the literature says. I rarely have any ED anymore in my practice.
Perhaps what has been attributed to neostigmine is in fact residual NM blocade
 
yes (and that's in private practice)

Damn... I work at an academic level 1 trauma center, and we are JUST getting Sugammadex in the next few weeks and we have the crappiest qualitative twitch monitors (which the CRNAs and residents always seem to put on the face even when having full access to at least one upper extremity... Any time I give a break, I switch it to the hand. It's little things like this that blow my mind.

That and seeing the BIS on "MAC" cases. We often do DEEEEEEP sedations, but c'mon... The BIS in general even for GETA cases... especially when it's reading in the 20s. If you're going to meaninglessly use it, at least adjust the anesthetic or don't waste money on it. There was a few weeks several months ago where we had a BIS shortage, and our incidence of awareness under anesthesia SKYROCKETED!!! Oh wait... no it didn't...

And finally Bair Huggers on top of the gown and 2 layers of blankets... Take the extra 30 seconds and do things appropriately...
 
Damn... I work at an academic level 1 trauma center, and we are JUST getting Sugammadex in the next few weeks and we have the crappiest qualitative twitch monitors (which the CRNAs and residents always seem to put on the face even when having full access to at least one upper extremity... Any time I give a break, I switch it to the hand. It's little things like this that blow my mind.

That and seeing the BIS on "MAC" cases. We often do DEEEEEEP sedations, but c'mon... The BIS in general even for GETA cases... especially when it's reading in the 20s. If you're going to meaninglessly use it, at least adjust the anesthetic or don't waste money on it. There was a few weeks several months ago where we had a BIS shortage, and our incidence of awareness under anesthesia SKYROCKETED!!! Oh wait... no it didn't...

And finally Bair Huggers on top of the gown and 2 layers of blankets... Take the extra 30 seconds and do things appropriately...

Whats wrong with monitor on face? Or bair hugger on top of things? You know the inventor of bair hugger is now going around saying it doesn't work well although thats probably financially motivated by his next new thing.
 
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