LMAs: technique

[Maverikk]

Advertisement - Members don't see this ad

whats your technique for getting a well seated LMA when one just won't seat. Have run into a spate of ones in moderately obese people that just wont seat. I really like the supreme for big people but don't have it now at my shop. For the classic I usually leave the red tab on so it doesnt deflate, give a good pull on the mandible then give a little air afterward taking off the tab, very rarely have to take it out and try again but this past week have had a few that just wouldnt do it, audible leak no matter the air amount, poor tidal volumes. Any pro tips for the classic, I'm missing the supreme

 

[AKMD_1984]

whats your technique for getting a well seated LMA when one just won't seat. Have run into a spate of ones in moderately obese people that just wont seat. I really like the supreme for big people but don't have it now at my shop. For the classic I usually leave the red tab on so it doesnt deflate, give a good pull on the mandible then give a little air afterward taking off the tab, very rarely have to take it out and try again but this past week have had a few that just wouldnt do it, audible leak no matter the air amount, poor tidal volumes. Any pro tips for the classic, I'm missing the supreme

If it does not sit well despite adequate attempts (which is once or twice) and I am not happy with ventilation, I just intubate. I have a low threshold for this.
LMAs are not perfect, so I treat them as such.

 

[DrOwnage]

At this point, I agree with above. Would you rather risk/deal with inadequate ventilation or just put a tube in? Most likely you have already created some trauma/mucosal irritation with either multiple LMA placements or readjustments or playing with the amount of air in the cuff. At that point you have to ask yourself what advantage does an LMA offer over the tube?

If it's for decrease in sore throat then you can throw that out the window. Patient is already "moderately obese," which would be an indication to throw a tube in someone over a BMI of 35, especially if in lithotomy.

I haven't had any one tactic work any better with a less than ideal seated LMA. Obviously ensure the patient is deep enough. If you think the epiglottis is smacked up over the LMA, sometimes I've found more neck extension while pulling the LMA a an inch or two out then shoving it back down works. In one retrospective review of approximately 19,700 anesthetics involving use of an SGA, use of SGA sizes 2 and 3 was associated with increased incidence of SGA failure. So going a size up most likely will be the answer rather than sizing down (uptodate stuff).

Someone is going to comment on using igel (someone always does), but I haven't used those/they're more expensive.

I personally hate LMA's and if there's any chance I'm questioning if its a good fit for the case, I'm throwing in a tube (unless the attending disagrees of course).

 

[Psai]

At this point, I agree with above. Would you rather risk/deal with inadequate ventilation or just put a tube in? Most likely you have already created some trauma/mucosal irritation with either multiple LMA placements or readjustments or playing with the amount of air in the cuff. At that point you have to ask yourself what advantage does an LMA offer over the tube?

If it's for decrease in sore throat then you can throw that out the window. Patient is already "moderately obese," which would be an indication to throw a tube in someone over a BMI of 35, especially if in lithotomy.

I haven't had any one tactic work any better with a less than ideal seated LMA. Obviously ensure the patient is deep enough. If you think the epiglottis is smacked up over the LMA, sometimes I've found more neck extension while pulling the LMA a an inch or two out then shoving it back down works. In one retrospective review of approximately 19,700 anesthetics involving use of an SGA, use of SGA sizes 2 and 3 was associated with increased incidence of SGA failure. So going a size up most likely will be the answer rather than sizing down (uptodate stuff).

Someone is going to comment on using igel (someone always does), but I haven't used those/they're more expensive.

I personally hate LMA's and if there's any chance I'm questioning if its a good fit for the case, I'm throwing in a tube (unless the attending disagrees of course).

Well there goes any contribution I thought I might make

 

[deleted87051]

In one retrospective review of approximately 19,700 anesthetics involving use of an SGA, use of SGA sizes 2 and 3 was associated with increased incidence of SGA failure. So going a size up most likely will be the answer rather than sizing down (uptodate stuff).

This. Upsizing reduces failure rates. You want a device that fills the volume of the pharynx at a low cuff pressure.

 

[narcusprince]

Igel lma. Get rid of the cuffed lmas have not placed a cuffed lma in a long long time.

 

[facted]

I'm my experience IGel does seat better and easier to place most of the time. More expensive though.

If I have another provide with me, I do two hand chin lift/jaw thrust as they place the LMA and it passes easily on 1st attempt almost every time.

To be honest, if I'm on call alone or at an outside site, I place ETT 99% of the time unless it's a super thin pt. Recently I didn't on a BMI 37 and the guy coughed 5 minutes into the case and the stomach contents coming out the LMA REALLY made me regret my decision.

 

[okayplayer]

whats your technique for getting a well seated LMA when one just won't seat. Have run into a spate of ones in moderately obese people that just wont seat. I really like the supreme for big people but don't have it now at my shop. For the classic I usually leave the red tab on so it doesnt deflate, give a good pull on the mandible then give a little air afterward taking off the tab, very rarely have to take it out and try again but this past week have had a few that just wouldnt do it, audible leak no matter the air amount, poor tidal volumes. Any pro tips for the classic, I'm missing the supreme

Igel

 

[Globulinus]

we don't have iGel in our shop, but Supreme are the 1st choice hands down..
Classics - get plunger out of 10cc syringe. Remove red tag and connect syringe to it. insert as usual, whatever you preference would be. Insert plunger back and inflate till no leak, usually no more then 10cc required..

If not successful 1st attempt - give 20-30 of sux and repeat attempt. Lately I started giving low dose sax almost routinely on lma induction. Works pretty well with troubleshooting lma during the case as well...

 

[caligas]

I think some times when you cannot initially ventilate through the LMA it has nothing to do with the position of the LMA, it’s just that the cords are closed or the patient is too light and they are coughing. Consider a bolus Of propofol/lido or even a cc or two of sux and the problem often fixed.

 

[Psai]

I think some times when you cannot initially ventilate through the LMA it has nothing to do with the position of the LMA, it’s just that the cords are closed or the patient is too light and they are coughing. Consider a bolus Of propofol/lido or even a cc or two of sux and the problem often fixed.

I'm taught not to ventilate since the patient will start breathing on their own

 

[narcusprince]

This. Upsizing reduces failure rates. You want a device that fills the volume of the pharynx at a low cuff pressure.

Thats what she said......

 

[Iso4ane]

Attendings have taught me to use a tongue depressor, to ' surprise surprise' depress the tongue and provide a smoother surface for the LMA to slide over.

 

[caligas]

I'm taught not to ventilate since the patient will start breathing on their own

Yes, one of the many pieces of dogma you will have to break free from after residency.

 

[facted]

Yes, one of the many pieces of dogma you will have to break free from after residency.

Nothing wrong with ventilating a patient if need be, but I'm a strong believer in getting pt breathing spontaneously. If there's an airway issue, esp in beach chair for shoulders, now you have one less thing to worry about...

 

[dannyboy1]

Nothing wrong with ventilating a patient if need be, but I'm a strong believer in getting pt breathing spontaneously. If there's an airway issue, esp in beach chair for shoulders, now you have one less thing to worry about...

Never understood why people will use the LMA for shoulders in beach chair. You have no easy access to the airway. If you have to take down the drapes to rescue the patient you can bet your @$$ that the surgeon will blame any infection/complications on you

 

[pgg]

I'm taught not to ventilate since the patient will start breathing on their own

You're a doctor with the power of critical thought, so you won't have this problem, but one issue I see recur with some regularity in certain providers who favor the non-ventilatory approach to LMA placement is this
1 - preoxygenation with some hyperventilation drives down CO2
2 - induce with propofol (+/- unnecessary fentanyl)
3 - LMA
4 - twist the knob on the sevo vaporizer
5 - techs prep for a quick surgery
6 - propofol + hypocarbia +/- opiate = no ventilatory drive
7 - propofol induction dose wears off about the time surgeon is ready to start
8 - ET sevo is a whopping 0.6% when the knife hits the patient
9 - movement, laryngospasm, all the joys of a light patient

Me, I think there's no downside to turning on the ventilator and delivering some anesthetic, so I just put them on the vent after placing the LMA. Everybody breathes when they're hypercarbic enough. What's the rush to get them spontaneous?

 

[pgg]

Attendings have taught me to use a tongue depressor, to ' surprise surprise' depress the tongue and provide a smoother surface for the LMA to slide over.

If an LMA won't pass easily first try, I use a piece of gauze to grab the tongue and pull it. They get a great jaw thrust, the tongue's out of the way, and the LMA slips in easily. Bonus points for freaking out new periop nurses.

 

[Maverikk]

Yeah I usually tube if it doesn't seat after 1-2 tries, no point in struggling for it. Just wanted to see what people did differently, I'll have to give the unplungered syringe trick a try. Most beach chair shoulders I would tube unless they looked particularly easy, having to readjust or having to tube half way through just isn't worth it.

 

[deleted87051]

Never understood why people will use the LMA for shoulders in beach chair. You have no easy access to the airway. If you have to take down the drapes to rescue the patient you can bet your @$$ that the surgeon will blame any infection/complications on you

Because it works very well. I’ve done nothing but LMA for beach chair shoulders for the past 18 years and have yet to encounter a problem or had to convert to an ETT. For successful lma use you need the correct LMA size (5 for men, 4 for women) and a patient who is not light.

 

[Twiggidy]

Because it works very well. I’ve done nothing but LMA for beach chair shoulders for the past 18 years and have yet to encounter a problem or had to convert to an ETT. For successful lma use you need the correct LMA size (5 for men, 4 for women) and a patient who is not light.

I mean, people breathe in the seated position all the time.

 

[Psai]

You're a doctor with the power of critical thought, so you won't have this problem, but one issue I see recur with some regularity in certain providers who favor the non-ventilatory approach to LMA placement is this
1 - preoxygenation with some hyperventilation drives down CO2
2 - induce with propofol (+/- unnecessary fentanyl)
3 - LMA
4 - twist the knob on the sevo vaporizer
5 - techs prep for a quick surgery
6 - propofol + hypocarbia +/- opiate = no ventilatory drive
7 - propofol induction dose wears off about the time surgeon is ready to start
8 - ET sevo is a whopping 0.6% when the knife hits the patient
9 - movement, laryngospasm, all the joys of a light patient

Me, I think there's no downside to turning on the ventilator and delivering some anesthetic, so I just put them on the vent after placing the LMA. Everybody breathes when they're hypercarbic enough. What's the rush to get them spontaneous?

I've never had the issue in 8 so maybe that's where the confusion lies

 

[propadope]

I'm taught not to ventilate since the patient will start breathing on their own

I would much rather ventilate and find out right away if the LMA is positioned properly then wait. Also I want to make sure there are no leaks with PPV. And to make sure there is no laryngospasm. The sooner you know the better

 

[propadope]

If an LMA won't pass easily first try, I use a piece of gauze to grab the tongue and pull it. They get a great jaw thrust, the tongue's out of the way, and the LMA slips in easily. Bonus points for freaking out new periop nurses.

This is my go to for all attempts. Its the epiglottis that often causes obstruction and I want to make sure its out of the way. Otherwise the LMA will get hung up in the vallecula or cause downfolding of the epiglottis

 

[spike7585]

Thoughts of LMA Supremes that dont seem to be seated properly but you're getting good tidal volumes and etco2? I've had a couple cases where the supreme didn't want to go further down, so the plastic tab (that usually for me tends to be flush with their upper lip) is sticking a few inches out. I've tried gently advancing, with no luck, but the couple I've noticed were for fairly short cases so I just lived with the half way stuck out LMA. Luckily no issues and tidal volumes we're normal.

 

[Globulinus]

Its rare occasion plastic tab sits exactly at the lip. Often 1/2 -1 inch or more higher.
I don't do anything if ventilation and seal is OK.
20 mg of Sux and jaw thrust on insertion made Supreme placement at least 95% 1st attempt success

 

[DocVapor]

This is my go to for all attempts. Its the epiglottis that often causes obstruction and I want to make sure its out of the way. Otherwise the LMA will get hung up in the vallecula or cause downfolding of the epiglottis

Just gotta say I'm glad you said this because I've had this happen to me once with an LMA classic. It was a podiatry case so easy enough to pull the LMA and tube thankfully. This is also why I also ventilate manually at least 2-3 times to make sure I can get good TV with minimal leak before letting them come back. I would rather know the LMA is going to work before the case gets started than after incision. Also my go-to technique for insertion is the tongue-grab technique as @propadope describe above. The trick to it is not losing the grip on the tongue until LMA is all the way down.

 

[Psai]

I would much rather ventilate and find out right away if the LMA is positioned properly then wait. Also I want to make sure there are no leaks with PPV. And to make sure there is no laryngospasm. The sooner you know the better

Oh my mistake, I definitely hand ventilate to check if we can get adequate tidal volumes. When I read ventilate I thought you guys meant putting the patient on vent control.

 

[BLADEMDA]

The key to using an LMA or any supraglottic device is recognizing when that device won't be successful for the case. The more you do the quicker you will recognize the need for plan B. Yes, they work most of the time, even the vast majority of the time, but in obese patients who belly breathe a lot the LMA may not be the airway device for that particular patient.

The posts above offer a lot of good advice so after several thousand LMA anesthetics most of the issues will become quite clear.

 

[Foodie]

Oh my mistake, I definitely hand ventilate to check if we can get adequate tidal volumes. When I read ventilate I thought you guys meant putting the patient on vent control.

We did mean that, or at least some of us did. After checking the seal with manual ventilation, I put pt on pressure control (<16 cm H2O), watching the tidal volume closely. When pt starts breathing on his own, I switch over to either spontaneous ventilation or pressure support mode.

If LMA seal is no bueno and I've tried to reposition or replace it more than once, I intubate and ask for a break because by that point I've worked too hard for a single case.

 

[propadope]

Oh my mistake, I definitely hand ventilate to check if we can get adequate tidal volumes. When I read ventilate I thought you guys meant putting the patient on vent control.

Sorry for the misunderstanding

 

[propadope]

Malpositioning of supraglottic airway devices: preventive and corrective strategies | BJA: British Journal of Anaesthesia | Oxford Academic

‘Failed supraglottic airway’: an algorithm for suboptimally placed supraglottic airway devices based on videolaryngoscopy | BJA: British Journal of Anaesthesia | Oxford Academic

Vision-guided placement of supraglottic airway device prevents airway obstruction: a prospective audit | BJA: British Journal of Anaesthesia | Oxford Academic

Its amazing how often LMAs are not ideally positioned