LMA vs ETT

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Please don't hurl insults when none are warranted. This is a civilized discussion ;)

This is not a discussion as to what is the best anesthetic. This is a discussion on how to minimize anesthetic dose which was your original point in favor of LMA's and which I disagree with.

What's "best" gets a whole lot more nuanced and a whole lot more subjective.

I'm saying that I do not have to give more anesthetic to overcome airway stimulation in a paralyzed pt.

I'm saying that I can give less volatile and less opioid to a paralyzed pt.

I'm saying that if my plan is paralyze the pt, then an ETT is a better choice than an LMA.

That is all.
Well you are wrong on many of these points and You might actually deserve those insults!

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Have you ever put an LMA in an awake patient? No? Oh, that's right, because they'd be gagging like crazy.

An LMA is probably 5-10x the diameter of a 7.0 ETT at the level of the posterior pharynx. While it doesn't touch the trachea like a lightly inflated cuff on an ETT does, it is gigantically stimulating in the upper airway.
I actually have done awake LMAs many times but with proper airway anesthesia! Why would you want to put something in the mouth of an awake patient?
And there is a difference between putting something in the oral cavity and inside the trachea... but most CRNAs wouldn't know that!
 
I actually have done awake LMAs many times but with proper airway anesthesia! Why would you want to put something in the mouth of an awake patient?
Ans there is a difference between putting something in the oral cavity and inside the trachea... but most CRNAs wouldn't know that!

Wait, so you talk about how stimulating an ETT in an awake patient with an improperly anesthetized airway and you compare it to an LMA with an anesthetized airway? I thought most physicians would understand the difference.

I'm also curious to hear the scenarios when you've felt the need/desire to place an LMA in an awake patient. I can't imagine one.
 
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Wait, so you talk about how stimulating an ETT in an awake patient with an improperly anesthetized airway and you compare it to an LMA with an anesthetized airway? I thought most physicians would understand the difference.
No... I am just responding to your strange example!
I wouldn't put an LMA in the mouth of an awake non anesthetized patient but that would definitely be better tolerated than an ETT in an awake non anesthetized patient!
Is that so complicated???
 
Well you are wrong on many of these points and You might actually deserve those insults!

Dude calm down. Again, you say I'm wrong without any explanation. Weak.

Please explain yourself because so far your arguments aren't making any sense.
 
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Have you ever put an LMA in an awake patient? No? Oh, that's right, because they'd be gagging like crazy.

An LMA is probably 5-10x the diameter of a 7.0 ETT at the level of the posterior pharynx. While it doesn't touch the trachea like a lightly inflated cuff on an ETT does, it is gigantically stimulating in the upper airway.

Yea, I didn't understand the awake intubation statement... unless of course he does his awake intubations with an LMA... which would be questionable in itself. But agreed that regardless of LMA or ETT an awake patient ain't tolerating either one of them!
 
Wait, so you talk about how stimulating an ETT in an awake patient with an improperly anesthetized airway and you compare it to an LMA with an anesthetized airway? I thought most physicians would understand the difference.

I'm also curious to hear the scenarios when you've felt the need/desire to place an LMA in an awake patient. I can't imagine one.
I just saw your edit...
There are occasions when you can put an intubating LMA in a known difficult intubation patient then intubate through that LMA... if that's your plan you need to make sure the patient's oral cavity and oropharynx are well anesthetized then it will work like charm.. but I agree with you... you probably have never seen this!
 
Yea, I didn't understand the awake intubation statement... unless of course he does his awake intubations with an LMA... which would be questionable in itself. But agreed that regardless of LMA or ETT an awake patient ain't tolerating either one of them!
So... since you have never seen an awake intubating LMA technique that makes it questionable?
 
I just saw your edit...
There are occasions when you can put an intubating LMA in a known difficult intubation patient then intubate through that LMA... if that's your plan you need to make sure the patient's oral cavity and oropharynx are well anesthetized then it will work like charm.. but I agree with you... you probably have never seen this!


Now I'M confused... if you're worried about an airway and are doing an awake FOI then why would you place an intubating LMA in first?! Why not just do the FOI with nothing or maybe an oral airway/OVasappian...? What advantage is shoving a huge LMA into an awake topicalized patient?
 
Now I'M confused... if you're worried about an airway and are doing an awake FOI then why would you place an intubating LMA in first?! Why not just do the FOI with nothing or maybe an oral airway/OVasappian...? What advantage is shoving a huge LMA into an awake topicalized patient?
It's one technique that you might want to learn but it doesn't mean it's the only technique!
It's helpful when you think that your fiberoptic is going to be challenging and you want a secure airway to start with.
 
It's one technique that you might want to learn but it doesn't mean it's the only technique!
It's helpful when you think that your fiberoptic is going to be challenging and you want a secure airway to start with.

Since when is an LMA a "secure" airway?
 
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Plank. Please explain to the class how any of those last 3 points I made are false.
Go back and read my posts...
A good anesthetic is not only about a patient not moving that's a CRNA anesthetic, an ETT is a foreign object in the trachea, and a muscle relaxant is not supposed to be part of every anesthetic!
 
It's one technique that you might want to learn but it doesn't mean it's the only technique!
It's helpful when you think that your fiberoptic is going to be challenging and you want a secure airway to start with.

MAybe in an emergency which is a completely different scenario. Obviously if a patient is on the floor crumping I might throw in an intubating LMA but if that's the case, the cat is already escaping the bag.

but I can't imagine doing an elective surgery on a known difficult airway where my first plan would be to shove an intubating LMA into their topicalized mouth... I dunno... maybe the next time I have an awake FOI I'll give it a whirl. Open WIDDDDEEEE!!!
 
Go back and read my posts...
A good anesthetic is not only about a patient not moving that's a CRNA anesthetic, an ETT is a foreign object in the trachea, and a muscle relaxant is not supposed to be part of every anesthetic!

This isn't about a "good" anesthetic. Re-read my posts. This is about you claiming you can get through a case with less anesthetic by using an LMA which is false.
 
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MAybe in an emergency which is a completely different scenario. Obviously if a patient is on the floor crumping I might throw in an intubating LMA but if that's the case, the cat is already escaping the bag.

but I can't imagine doing an elective surgery on a known difficult airway where my first plan would be to shove an intubating LMA into their topicalized mouth... I dunno... maybe the next time I have an awake FOI I'll give it a whirl. Open WIDDDDEEEE!!!
You really need to keep an open mind to learn techniques that no one taught you
 
You really need to keep an open mind to learn techniques that no one taught you


Never said it can't be done. But not sure how much more advantageous that is than using an oral airway. As mentioned, LMA does not equal secure. And if you're not sedating the patient, then what risk do you have of losing the airway in the first place in an elective case? Either way, the patient has to be realy well anesthetized to tolerate the LMA and you're still putting the ETT into the trachea, so how does that prove that the LMA is less irritating in an non-topicalized patient?
 
Never said it can't be done. But not sure how much more advantageous that is than using an oral airway. As mentioned, LMA does not equal secure. And if you're not sedating the patient, then what risk do you have of losing the airway in the first place in an elective case? Either way, the patient has to be realy well anesthetized to tolerate the LMA and you're still putting the ETT into the trachea, so how does that prove that the LMA is less irritating in an non-topicalized patient?

In fact if the patient is poorly topicalized I bet doing an awake FOI without an LMA is probably easier than doing it with an LMA. But I doubt any IRB would let that study go through...
 
Never said it can't be done. But not sure how much more advantageous that is than using an oral airway. As mentioned, LMA does not equal secure. And if you're not sedating the patient, then what risk do you have of losing the airway in the first place in an elective case? Either way, the patient has to be realy well anesthetized to tolerate the LMA and you're still putting the ETT into the trachea, so how does that prove that the LMA is less irritating in an non-topicalized patient?
I was just letting you know that it can be done since you obviously never learned it!
And I was hoping that you would concede that although you think you learned everything there is to learn in medicine there might be somethings that you can still learn!
 
Ok Plank. Let's give an example. Say you are faced with a 3 hour case that's not amenable to regional and does not require paralysis. The pt is otherwise healthy but tells you they are very sensitive to anesthesia and "it always takes them forever to wake up" and they spend forever in PACU as a result.

If you do the case with an LMA you're gonna have to run them at essentially MAC levels the whole time so they don't wiggle.

If you slap in an ETT and use relaxant then you can run them at say 0.6 MAC the whole time.

Why is that too difficult for you to understand?? Could you pop in an LMA and then relax them? Sure but I'm not sure what you gain by doing that.
 
In fact if the patient is poorly topicalized I bet doing an awake FOI without an LMA is probably easier than doing it with an LMA. But I doubt any IRB would let that study go through...
Awake intubation is an art and there are many techniques and many airway anesthesia approaches that could be learned if you ask your attendings to teach you.
 
Ok Plank. Let's give an example. Say you are faced with a 3 hour case that's not amenable to regional and does not require paralysis. The pt is otherwise healthy but tells you they are very sensitive to anesthesia and "it always takes them forever to wake up" and they spend forever in PACU as a result.

If you do the case with an LMA you're gonna have to run them at essentially MAC levels the whole time so they don't wiggle.

If you slap in an ETT and use relaxant then you can run them at say 0.6 MAC the whole time.

Why is that too difficult for you to understand?? Could you pop in an LMA and then relax them? Sure but I'm not sure what you gain by doing that.
This would be an ideal case for an LMA with a good balanced anesthetic, and I can assure you that they will wake up great.
Now what agents and what analgesics or regional technique I would use would be case specific, but they will get the best anesthetic possible!
 
This would be an ideal case for an LMA with a good balanced anesthetic, and I can assure you that they will wake up great.
Now what agents and what analgesics or regional technique I would use would be case specific, but they will get the best anesthetic possible!

Way to dodge what I'm saying :thumbup:
 
Have you ever put an LMA in an awake patient? No? Oh, that's right, because they'd be gagging like crazy.

An LMA is probably 5-10x the diameter of a 7.0 ETT at the level of the posterior pharynx. While it doesn't touch the trachea like a lightly inflated cuff on an ETT does, it is gigantically stimulating in the upper airway.

I have seen pressure injuries from an over inflated cuff on an LMA including a permanent recurrent laryngeal nerve palsy from an LMA on a long case. Not to say that you can't get pressure injury from an over inflated cuff on an ETT. But LMAs are not benign and can cause injury especially in a long case. And LMAs do leave the airway unprotected, they do often leak anesthetic gases into the OR, and they cannot hold pressures above about 20 cm of water, sometimes they cause a bloody mess on insertion. These discussions are fun, but LMA vs ETT is ridiculous. Give me any excuse and I will put in an ETT. And I like using LMAs!
 
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Awake intubation is an art and there are many techniques and many airway anesthesia approaches that could be learned if you ask your attendings to teach you.

Your point was that an LMA is less stimulating, and then use an example of a very well topicalized patient/anesthesiologist placing an LMA in his mouth... Again, that video would look exactly the same if they used an LMA, nothing, a bite block, an oral airway, an Ovassapian, a glidescope, etc.

I've done tons of awake FOIs... I did one my 2nd day of being an attending and it went smoothly. A week later they struggled to do a bronch on the same patient. MY former attendings taught me well. Again, I know there are a ton of different ways to do awake intubations, I just think an awake LMA isn't my top choice. And like I stated I feel that in a well topicalized airway, there really isn't any advantage to the LMA, and if not well topicalized would probably be worse than most of the other methods mentioned.
 
I have seen pressure injuries from an over inflated cuff on an LMA including a permanent recurrent laryngeal nerve palsy from an LMA on a long case. Not to say that you can't get pressure injury from an over inflated cuff on an ETT. But LMAs are not benign and can cause injury especially in a long case. And LMAs do leave the airway unprotected, they do often leak anesthetic gases into the OR, and they cannot hold pressures above about 20 cm of water, sometimes they cause a bloody mess on insertion. These discussions are fun, but LMA vs ETT is ridiculous. Give me any excuse and I will put in an ETT. And I like using LMAs!

Mad props to the guy who did the prone case with an LMA. Yea it's possible, but no amount of "less PONV" or "faster wakeup" would give me the balls to do that. Upside down patient in MY books is a contraindication to an LMA... People can argue one way or another reasons to use them, but I personally wouldn't find any reason to do that.
 
Your point was that an LMA is less stimulating, and then use an example of a very well topicalized patient/anesthesiologist placing an LMA in his mouth... Again, that video would look exactly the same if they used an LMA, nothing, a bite block, an oral airway, an Ovassapian, a glidescope, etc.

I've done tons of awake FOIs... I did one my 2nd day of being an attending and it went smoothly. A week later they struggled to do a bronch on the same patient. MY former attendings taught me well. Again, I know there are a ton of different ways to do awake intubations, I just think an awake LMA isn't my top choice. And like I stated I feel that in a well topicalized airway, there really isn't any advantage to the LMA, and if not well topicalized would probably be worse than most of the other methods mentioned.
I am not saying it's the best option but it is an option in a patient with significantly redundant soft tissue that will make you fiberoptic very challenging.
 
Whoa

:whoa:

Never thought I'd see the day when Plankton was the one being bizarrely dogmatic about something.

I don't know which way is up any more.
I am not dogmatic about this, and trust me when a patient needs an ETT the patient will get an ETT, but I am a strong believer in "less is better", and in my opinion an LMA is less invasive than an ETT so it is better if the situation permits.
That's all!
 
Have you ever put an LMA in an awake patient? No? Oh, that's right, because they'd be gagging like crazy.

An LMA is probably 5-10x the diameter of a 7.0 ETT at the level of the posterior pharynx. While it doesn't touch the trachea like a lightly inflated cuff on an ETT does, it is gigantically stimulating in the upper airway.
That "lightly" inflated cuff is almost never lightly inflated. Most people put 10 cc's of air in that cuff. If you ever watch a respiratory tech in the ICU, you will see that they need less than 5-6 cc's for proper cuff pressures in most patients.

Also, most of us insert the tube too deeply, because the safe tube depths we are taught err on the side of bronchial intubation (vs. accidental extubation). I recently read about a case where the patient had bronchial intubation with the tube taped at 20 cm. My point is that the area of the carina is very sensitive to stimulation (almost like a surgical stimulus), this is why withdrawing the tube sometimes helps with bucking.

An experienced anesthesiologist will avoid overinflating the LMA exactly because, as you said, the contact area with the pharynx is much larger, meaning that it will give a very bad sore throat. And while the pharynx is a reflexogenic area, it's nothing like the carina AFAIK. I have never seen anybody brady down from an LMA, but I have seen almost cardiac arrest after deep suctioning through an ETT in the ICU.

Anyway, there are cases where the LMA is optimal, cases where the ETT is the only one indicated, and grey areas. We all agree about the former two, and we shouldn't fight about the latter.
 
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If you do the case with an LMA you're gonna have to run them at essentially MAC levels the whole time so they don't wiggle.

If you slap in an ETT and use relaxant then you can run them at say 0.6 MAC the whole time.
.
I'm just skimming thru this thread and am not as passionate on this topic as others here, but I have to say that this statement is false. I placed 4 LMA's today and ran them all at around 0.5 MAC. Each one woke up to my voice as the drapes were coming down. No paralytics
 
I'm just skimming thru this thread and am not as passionate on this topic as others here, but I have to say that this statement is false. I placed 4 LMA's today and ran them all at around 0.5 MAC. Each one woke up to my voice as the drapes were coming down. No paralytics

1. What were the cases?
2. Assuming you also used narcs?
3. Local/blocks used?
 
I've done tons of awake FOIs... I did one my 2nd day of being an attending and it went smoothly. A week later they struggled to do a bronch on the same patient.
Another proof that what's above the vocal cords is way less reflexogenic than some parts of the tracheobronchial tree.
 
That "lightly" inflated cuff is almost never lightly inflated. Most people put 10 cc's of air in that cuff. If you ever watch a respiratory tech in the ICU, you will see that they need less than 5-6 cc's for proper cuff pressures in most patients.

Also, most of us insert the tube too deeply, because the safe tube depths we are taught err on the side of bronchial intubation (vs. accidental extubation). I recently read about a case where the patient had bronchial intubation with the tube taped at 20 cm. My point is that the area of the carina is very sensitive to stimulation (almost like a surgical stimulus), this is why withdrawing the tube sometimes helps with bucking.

An experienced anesthesiologist will avoid overinflating the LMA exactly because, as you said, the contact area with the pharynx is much larger, meaning that it will give a very bad sore throat. And while the pharynx is a reflexogenic area, it's nothing like the carina AFAIK. I have never seen anybody brady down from an LMA, but I have seen almost cardiac arrest after deep suctioning through an ETT in the ICU.

Anyway, there are cases where the LMA is optimal, cases where the ETT is the only one indicated, and grey areas. We all agree about the former two, and we shouldn't fight about the latter.

1) The cuff is always properly inflated when I'm in the room. Just because an RT might overdo it in the ICU doesn't mean anybody with me is screwing it up.
2) You can almost always feel the cuff just above the sternum (as long as they aren't gigantically fat) to insure you aren't even close to mainstem intubation
3) Can you use an LMA in lots of cases? Of course. Just don't pretend it decreases the incidence of PONV or leads to faster PACU discharges. It doesn't. An unskilled anesthesiologist or CRNA is the only thing leading to increase in those outcomes.
 
Just don't pretend it decreases the incidence of PONV or leads to faster PACU discharges. It doesn't. An unskilled anesthesiologist or CRNA is the only thing leading to increase in those outcomes.
ETT requires deeper anesthetic levels to maintain anesthesia and that leads to more PONV and longer PACU stay!
Unskilled anesthesiologists and CRNAs like to intubate and paralyze every patient and as a result they get more PONV and longer PACU stays.
These are simple facts that everyone knows!
 
ETT requires deeper anesthetic levels to maintain anesthesia and that leads to more PONV and longer PACU stay!
Unskilled anesthesiologists and CRNAs like to intubate and paralyze every patient and as a result they get more PONV and longer PACU stays.
These are simple facts that everyone knows!

If you use an LMA and you want your patient to not move during surgery you need
a) a MAC+ of volatile, or
b) less than a MAC of volatile plus something else with a partial MAC equivalent (opiate, benzo, ketamine, etc) OR effective regional/local, or
c) paralytic

Most sane people don't use a pure volatile technique for either a LMA or ETT case. The point everyone else has been making in this thread is that (absent a regional technique providing a surgical level block) the depth of anesthesia required to tolerate the procedure is going to be sufficient to tolerate either a LMA or ETT.

This notion that general anesthetics with ETTs somehow always (or even usually) require deeper levels of anesthesia is bizarre.

These are simple facts that everyone knows. :)


I agree with you, that beginners and unskilled people lean on paralytics as a crutch to get through inelegant / unbalanced anesthetics with ETTs. But IMO paralytics are way overused in general, and I think you're confusing that problem to be related to the airway device chosen.

Avoiding excessive muscle relaxant and the cost/PONV associated with reversal is a good thing. It's possible to do that with an ETT, especially in the sort of cases that can be reasonably done with LMAs.

To each his own (and again I like to use LMAs in simple cases to keep them a little simpler) but dogmatically declaring that "ETT requires deeper anesthetic levels to maintain anesthesia and that leads to more PONV and longer PACU stays" is just wrong.
 
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If you use an LMA and you want your patient to not move during surgery you need
a) a MAC+ of volatile, or
b) less than a MAC of volatile plus something else with a partial MAC equivalent (opiate, benzo, ketamine, etc) OR effective regional/local, or
c) paralytic

Most sane people don't use a pure volatile technique for either a LMA or ETT case. The point everyone else has been making in this thread is that (absent a regional technique providing a surgical level block) the depth of anesthesia required to tolerate the procedure is going to be sufficient to tolerate either a LMA or ETT.

This notion that general anesthetics with ETTs somehow always (or even usually) require deeper levels of anesthesia is bizarre.

These are simple facts that everyone knows. :)


I agree with you, that beginners and unskilled people lean on paralytics as a crutch to get through inelegant / unbalanced anesthetics with ETTs. But IMO paralytics are way overused in general, and I think you're confusing that problem to be related to the airway device chosen.

Avoiding excessive muscle relaxant and the cost/PONV associated with reversal is a good thing. It's possible to do that with an ETT, especially in the sort of cases that can be reasonably done with LMAs.

To each his own (and again I like to use LMAs in simple cases to keep them a little simpler) but dogmatically declaring that "ETT requires deeper anesthetic levels to maintain anesthesia and that leads to more PONV and longer PACU stays" is just wrong.
Although I appreciate the educational gesture but I have to repeat my points again:
Maintaining an anesthetic with an ETT requires more anesthesia than maintaining the anesthetic with an LMA for a given procedure because a foreign body in the trachea and possibly touching the carina is probably the worst stimulation you can do to a patient!
More anesthesia means either more inhaled agent, more opiate, and / or adding a muscle relaxant.
Giving more inhaled agents or opiates will increase PONV and delay PACU discharge (I hope you agree with this one)
Giving a muscle relaxant will require reversal that would as well increase PONV (forget Sugammadex for a second)
One other little point is that an LMA is associated with shorter end of surgery to out of OR time.
And LMAs decrease the stress response of intubation and extubation which could mean less peri-op cardiac complications.
And LMAs lower the chances of dental injury!
So why would any one intubate a patient if the case can be done with an LMA???
But again thank you for your educational input!
 
Although I appreciate the educational gesture but I have to repeat my points again:
Maintaining an anesthetic with an ETT requires more anesthesia than maintaining the anesthetic with an LMA for a given procedure because a foreign body in the trachea and possibly touching the carina is probably the worst stimulation you can do to a patient!
More anesthesia means either more inhaled agent, more opiate, and / or adding a muscle relaxant.
Giving more inhaled agents or opiates will increase PONV and delay PACU discharge (I hope you agree with this one)
Giving a muscle relaxant will require reversal that would as well increase PONV (forget Sugammadex for a second)
One other little point is that an LMA is associated with shorter end of surgery to out of OR time.
And LMAs decrease the stress response of intubation and extubation which could mean less peri-op cardiac complications.
And LMAs lower the chances of dental injury!
So why would any one intubate a patient if the case can be done with an LMA???
But again thank you for your educational input!
I must say that "in general" I agree with all of this.
However, I think SaltyDog has points as well and I can see where he is coming from.
My general feeling is that ETT's are more stimulating and therefore require more anesthesia however, there are ways around this. So a skilled anesthesiologist can easily achieve with an ETT what he or she can achieve with an LMA.
For example, when I was a resident and even a newer attending my wake ups were probably slower with the ETT in place. Nowadays, there is virtually no difference. Both "usually" come out with the last stich or as the surgical team is reaching for the drapes. Recovery times are equal and while it is hard to quantify since I use ETT and LMA' s in different types of cases, PONV is equal. This took me some time to master and therefore it does not speak to every anesthesiologist.
 
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I must say that "in general" I agree with all of this.
However, I think SaltyDog has points as well and I can see where he is coming from.
My general feeling is that ETT's are more stimulating and therefore require more anesthesia however, there are ways around this. So a skilled anesthesiologist can easily achieve with an ETT what he or she can achieve with an LMA.
For example, when I was a resident and even a newer attending my wake ups were probably slower with the ETT in place. Nowadays, there is virtually no difference. Both "usually" come out with the last stich or as the surgical team is reaching for the drapes. Recovery times are equal and while it is hard to quantify since I use ETT and LMA' s in different types of cases, PONV is equal. This took me some time to master and therefore it does not speak to every anesthesiologist.
Agree!
But remember... you do your own cases... most of us unfortunately don't!
 
Anyone use those LMAs that you can pass an OG through to suction out the stomach?
I don't like the way they seat as well. I will use them from time to time but I have never tried to place an OG down one. If I want to suction that stomach at all, I'm placing an ETT, period.
I guess if you couldn't intubate for some reason and had to go with an LMA then possibly it would be an option but I've never been in that situation.
 
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My day would be so much less enjoyable if I just had to watch people give anesthesia all day.
 
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