when to use LMA?

[IFNgamma]

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rookie question: (as I am still very much a rookie at this)

I'm still not entirely sure of the indication for LMA vs. ETT. I've read Barash, baby Miller, and they don't really say which cases are good for LMA.

from wut I understand, you use LMA when:
1) don't need intubation, but controlled ventilation still desired
2) short procedure
3) part of difficult airway algorithm, as conduit to intubation

Can some veterans here give a more practical explanation of when and when not to use LMA? Like which cases are perfect for LMA and which absolutely not?

 

[jwk]

rookie question: (as I am still very much a rookie at this)

I'm still not entirely sure of the indication for LMA vs. ETT. I've read Barash, baby Miller, and they don't really say which cases are good for LMA.

from wut I understand, you use LMA when:
1) don't need intubation, but controlled ventilation still desired
2) short procedure
3) part of difficult airway algorithm, as conduit to intubation

Can some veterans here give a more practical explanation of when and when not to use LMA? Like which cases are perfect for LMA and which absolutely not?

Among others...

D&C
knee scopes and virtually any peripheral orthopedic surgery
many plastic surgery cases including facelifts
breast surgery
cysto
non-laparoscopic GYN surgery

and a zillion others.

Some will use them for laparoscopic procedures and prone cases - I don't and won't.

 

[dfk]

any time it's safe to mask a case, you can use an LMA

 

[Idiopathic]

I actually look for reasons to use them. If the case is going to be exceptionally long, you have a sick patient or you think an endotracheal intubation would be difficult, I will avoid LMA.

I dont want to have to intubate a patient under the drapes or in the middle of surgery if the PIP goes to 40 and you cant ventilate through an LMA. Ive had to do this before and if the airway were perceived as difficult then you certainly wouldnt feel like you were in control under those circumstances. Just my two cents.

With that said, yes an LMA is in your difficult airway algorithm, but I usually use it as an adjunct to a secure airway in those times.

 

[Planktonmd]

When to use an LMA:
Any general anesthetic where the aspiration risk is not too high.
And always remember that most of the time people aspirate because they have light anesthesia not because they have an LMA.

 

[2ndyear]

My question (probably more for old timers) is when did 'GERD' develop timewise? We're all taught in residency to avoid LMA's if bad GERD, use Bicitra/Reglan/Zantac then sux. But did people always have GERD? I mean, there was a time when plenty of anesthesia was done before ETT, right. Did people not have GERD? Or did we just not care. I'm not all that old, but I still don't recall antacids playing a prominent role in television ads like they do today. Is it because of the obesity epidemic?

 

[Planktonmd]

My question (probably more for old timers) is when did 'GERD' develop timewise? We're all taught in residency to avoid LMA's if bad GERD, use Bicitra/Reglan/Zantac then sux. But did people always have GERD? I mean, there was a time when plenty of anesthesia was done before ETT, right. Did people not have GERD? Or did we just not care. I'm not all that old, but I still don't recall antacids playing a prominent role in television ads like they do today. Is it because of the obesity epidemic?

I don't ask about GERD anymore I only ask them if they have heart burn right now.
90 % of the patients I put LMA's in have some sort of GERD diagnosis.

 

[IFNgamma]

I don't ask about GERD anymore I only ask them if they have heart burn right now.
90 % of the patients I put LMA's in have some sort of GERD diagnosis.

huh? you just said not to use LMA in a patient when the risk of aspiration is high, yet you use LMA on pt's with GERD 90% of the time? doesn't make sense.

anyways, I put in an LMA today, pretty easy, the patient was rock stable the whole case, didn't have to do anything, didn't have to check twitches, no reversal, pretty cool. Seems like LMAs are under-utilized.

 

[huktonfonix]

huh? you just said not to use LMA in a patient when the risk of aspiration is high, yet you use LMA on pt's with GERD 90% of the time? doesn't make sense.

anyways, I put in an LMA today, pretty easy, the patient was rock stable the whole case, didn't have to do anything, didn't have to check twitches, no reversal, pretty cool. Seems like LMAs are under-utilized.

Most people will say they have some form of reflux, most of it doesnt place you at increased risk for aspiration. I get reflux after a big spicy meal + alcohol. I wouldnt hesitate to get an LMA for surgery. Besides microaspiration happens all the time with an ETT anyway.

 

[core0]

My question (probably more for old timers) is when did 'GERD' develop timewise? We're all taught in residency to avoid LMA's if bad GERD, use Bicitra/Reglan/Zantac then sux. But did people always have GERD? I mean, there was a time when plenty of anesthesia was done before ETT, right. Did people not have GERD? Or did we just not care. I'm not all that old, but I still don't recall antacids playing a prominent role in television ads like they do today. Is it because of the obesity epidemic?

Cimetidine became available on January 1, 1979. This was when GERD first occurred. Before that everyone had "heartburn". This post brought to you by GlaxoSmithKline and the letter E.

David Carpenter, PA-C

 

[emergiQ]

huh? you just said not to use LMA in a patient when the risk of aspiration is high, yet you use LMA on pt's with GERD 90% of the time? doesn't make sense.

anyways, I put in an LMA today, pretty easy, the patient was rock stable the whole case, didn't have to do anything, didn't have to check twitches, no reversal, pretty cool. Seems like LMAs are under-utilized.

Under utilized here. Ask any of your Brit-Irish-SAfrican faculty members (as is inevitably the case in any good academic department in this country) and they'll tell you they're much more routine at home. Er, their home.

I cross pollinate as an ER doc... I like the comfort of knowing that an intubating LMA is in my armamentarium, too.

 

[Sonny Crocket]

what do you guys think of using an LMA for a patient with a known difficult intubation(but easy to mask ventilate) from before?

Had a patient the other night. Big dude. Lean/tall and just a large person. Airway looks fine. He has a card with him from another hospital where anesthesiologist has written that they used cmac and boughie to intubate and that mask ventilation was not a problem. He's coming in for a compartment syndrome in left leg. Had a sip of soup at 6pm otherwise Been fasting since 10 am. It's now 10:30 at night. Surgeon needs 30min.

I struggle to intubate this guy and end up doing the case with an LMA after inducing with prop/sux/fent. Case takes about an hour and goes fine. Kept him deep. I realize that there is an aspiration risk here but I had manipulated the airway 3 times and the LMA was working well.

 

[Planktonmd]

what do you guys think of using an LMA for a patient with a known difficult intubation(but easy to mask ventilate) from before?

Had a patient the other night. Big dude. Lean/tall and just a large person. Airway looks fine. He has a card with him from another hospital where anesthesiologist has written that they used cmac and boughie to intubate and that mask ventilation was not a problem. He's coming in for a compartment syndrome in left leg. Had a sip of soup at 6pm otherwise Been fasting since 10 am. It's now 10:30 at night. Surgeon needs 30min.

I struggle to intubate this guy and end up doing the case with an LMA after inducing with prop/sux/fent. Case takes about an hour and goes fine. Kept him deep. I realize that there is an aspiration risk here but I had manipulated the airway 3 times and the LMA was working well.

I think doing a case with an LMA in a previously diagnosed difficult airway is a great idea although that wouldn't be the best answer for the oral boards.

 

[deleted171991]

I think doing a case with an LMA in a previously diagnosed difficult airway is a great idea although that wouldn't be the best answer for the oral boards.

If the case is not too long and the patient is lean and easy to ventilate, I think it's a much better solution than playing AFOI. One just has to pay attention to maintaining a tidal volume of 500+, to avoid atelectasis.

Soup shouldn't be a problem if it was just a sip (and the patient is reliable). I would put in a Supreme and suction the stomach if I can (not really necessary), and give at least metoclopramide after induction (and famotidine if available). I find that the most dangerous patients are the nervous ones, with a ton of gastric and biliary secretions from stress, even if healthy.

Oral boards anesthesia is about not making any risky compromises. Real-life anesthesia is about making the right compromises.

 

[nap$ter]

what do you guys think of using an LMA for a patient with a known difficult intubation(but easy to mask ventilate) from before?

Had a patient the other night. Big dude. Lean/tall and just a large person. Airway looks fine. He has a card with him from another hospital where anesthesiologist has written that they used cmac and boughie to intubate and that mask ventilation was not a problem. He's coming in for a compartment syndrome in left leg. Had a sip of soup at 6pm otherwise Been fasting since 10 am. It's now 10:30 at night. Surgeon needs 30min.

I struggle to intubate this guy and end up doing the case with an LMA after inducing with prop/sux/fent. Case takes about an hour and goes fine. Kept him deep. I realize that there is an aspiration risk here but I had manipulated the airway 3 times and the LMA was working well.

this is the perfect LMA case. dunno why you tried to intubate him in the first place. a true sip of soup 4.5 hrs ago isn't a concern for me...

 

[BLADEMDA]

what do you guys think of using an LMA for a patient with a known difficult intubation(but easy to mask ventilate) from before?

Had a patient the other night. Big dude. Lean/tall and just a large person. Airway looks fine. He has a card with him from another hospital where anesthesiologist has written that they used cmac and boughie to intubate and that mask ventilation was not a problem. He's coming in for a compartment syndrome in left leg. Had a sip of soup at 6pm otherwise Been fasting since 10 am. It's now 10:30 at night. Surgeon needs 30min.

I struggle to intubate this guy and end up doing the case with an LMA after inducing with prop/sux/fent. Case takes about an hour and goes fine. Kept him deep. I realize that there is an aspiration risk here but I had manipulated the airway 3 times and the LMA was working well.

I think you did a good job here. My approach would have been to give Zantac and Reglan then wait 30 minutes followed by an LMA. I wouldn't have performed a Glidescope or awake FOI on him.

I don't trust patients who claim they only had one sip or one bite of anything. I'm wiling to bend somewhat on the NpO rules but prefer a little extra precaution with the premeds listed above.

Depending on my mood that day I may have used this LmA :
http://www.lmana.com/pwpcontrol.php?pwpID=6347

 

[BLADEMDA]

 

[deleted171991]

Did you find this in the Wood Library-Museum? 😛

Seriously, the part about deflating the LMA, before even trying to insert it, cracks me up. Not to speak about the manometry. Or the vent-noise.

Residents, always inflate the LMA to the lowest pressure that still provides a good seal. There is no magic number, but the balloon should be easy to compress. If it's a kid or a long case, a manometer should prevent injury. But nothing prevents injury more than smooth insertion of the right type and size LMA on the first attempt, followed by finding the depth at which the seal is the best, hence the cuff pressure the lowest. The difference between being good or bad at LMAs is <3% versus >25% sore throat.

The problem with blindly following the numbers listed on the packaging, and/or deflating the LMA before insertion is that one might insert an LMA which is too big. It might be easier to get a seal, but the risk of sore throat increases, too. Supreme is the classical example.

 

[Sonny Crocket]

this is the perfect LMA case. dunno why you tried to intubate him in the first place. a true sip of soup 4.5 hrs ago isn't a concern for me...

Because the guy was in pain from compartment syndrome.

 

[BLADEMDA]

Because the guy was in pain from compartment syndrome.

Sonny, the longer your at this game the more you realize that doing the right thing in the real world is sometimes different than academia. IMHO, you did a good job handling that case and maybe next time you will proceed directly to the LMA; or, perhaps you will just do the same approach.

 

[nap$ter]

Because the guy was in pain from compartment syndrome.

i agree with blade your management and outcome were OK and defensible.

why does pain from compartment syndrome mandate an ett instead of an LMA tho?

i still would have started with an LMA here...

 

[risnwb]

i agree with blade your management and outcome were OK and defensible.

why does pain from compartment syndrome mandate an ett instead of an LMA tho?

i still would have started with an LMA here...

pain resulting in slowed gastric emptying from sns stimulation?

 

[deleted171991]

why does pain from compartment syndrome mandate an ett instead of an LMA tho?

Pain decreases stomach motility and evacuation. Hence the reason to always do RSI in trauma, even if NPO.

 

[Sonny Crocket]

How much pain is enough to warrant an ETT? Another grey area.

 

[nap$ter]

Pain decreases stomach motility and evacuation. Hence the reason to always do RSI in trauma, even if NPO.

i love academic dogma.

what is your cutoff lab value for pain sufficient to mandate an ett?

life is pain, son.

RSI's are almost always good for trauma. How much trauma tho? How much NPO time?

Do you do an RSI for a mormon on fast sunday after breaking his arm in the afternoon falling off his bike on the way home from church? 2hr case with a block?

 

[fakin' the funk]

One just has to pay attention to maintaining a tidal volume of 500+, to avoid atelectasis.

???? Where are you coming up with this

 

[deleted171991]

???? Where are you coming up with this

In the phrase that you quoted, I was trying to suggest that one can do even longer cases with LMAs, as long as one pays attention to preventing atelectasis.

I find that maintaining a tidal volume of at least 6-7 ml/kg of ideal weight (500 for an average adult) prevents atelectasis, even after a few hours. I don't really insist on it unless the case is long and the patient truly obese. I run PCV on all my patients, so this corresponds to decently low PIPs (when compared to VCV) and little if any barotrauma. But, since I started doing this, I haven't had problems with intraop atelectasis and difficulty ventilating in the middle of a case.

 

[Twiggidy]

rookie question: (as I am still very much a rookie at this)

I'm still not entirely sure of the indication for LMA vs. ETT. I've read Barash, baby Miller, and they don't really say which cases are good for LMA.

from wut I understand, you use LMA when:
1) don't need intubation, but controlled ventilation still desired
2) short procedure
3) part of difficult airway algorithm, as conduit to intubation,

Can some veterans here give a more practical explanation of when and when not to use LMA? Like which cases are perfect for LMA and which absolutely not?

Any procedure that isn't intra abdominal or in the airway.....basically (except pump cases, thorax, and cranis)...use judgement