What’s your cut off case time for an LMA?

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ItBurnsInMyHand

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How long is too long? And any other pearls you care to share.

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Asked myself the same question when I started. Usually 3 hours or 4 hours max. Major issues as far as I know are lingual nerve palsy, increased aspiration risk for a prolonged case, and increased pressure support requirements over time. My BMI cutoff is usually around 40 and in those cases <2 hours.
 
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I also aim for around 2 hours but I've had lma cases go for 5+ hours with no issues. I check the tongue during the case.
 
So if a patient breaths spontaneously, with a glorified oral airway in their mouth, for 5 hours, it's too long? Darn, what's your cutoff for propofol MAC cases (e.g. podiatry)? How about life and spontaneous ventilation, in general? 😛

On the serious side, as long as I have a channel to suction the stomach, and as long as the cuff is adjustable (lower risk of tissue injury and better individual fit), I have done 4-5 hour cases, even with muscle-relaxation and controlled ventilation. Obviously, it also depends on the patient.
 
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2 hours for me. Also wouldn’t do it for a morbidly obese patient no matter how long the case is.
I would, and have done it. The alternative would have been a difficult intubation for a cysto. It's all a matter of risks vs benefits.

How many obese (or diabetic) NPO patients have you seen with residual solid food (not just particles) on an EGD? I have seen just one, and that applies to many hundreds of patients.
 
Agree with above, risks vs benefits, never clear cut and dry. I always had an attending tell me in residency "LMAs are for lazy anesthesiologists". You have to ask yourself what is the benefit to putting in an LMA vs a tube. When it boils down to it, there isn't many benefits. The decreased sore throat never convinced me, maybe less hoarseness. I would add I don't put LMAs in patients when the positioning is high lithotomy regardless of BMI.
 
Agree with above, risks vs benefits, never clear cut and dry. I always had an attending tell me in residency "LMAs are for lazy anesthesiologists". You have to ask yourself what is the benefit to putting in an LMA vs a tube. When it boils down to it, there isn't many benefits. The decreased sore throat never convinced me, maybe less hoarseness. I would add I don't put LMAs in patients when the positioning is high lithotomy regardless of BMI.
I am absolutely lazy (on my own scale; and absolutely hardworking when I sometimes look around, hehe). A lot of truly good doctors are lazy, because one needs that motivation to figure out what works in medicine and what doesn't, what's true and what's legend from all the "evidence-based" BS. That's also why one can learn so much from watching other anesthesiologists; we have an eye towards optimization and simplification.

There is an entire thread about the benefits of an LMA (vs ETT). Also, let's not forget how we used to make fun of people who used ultrasound for line placement. Just because it's different or simpler, it doesn't mean it's wrong, as long as the outcomes are not worse.
 
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lol... so what is the downside of “long” lma times in a spontaneously breathing patient with a little pressure support?
 
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I would encourage younger anesthesiologists to be at least somewhat selective with LMA use. It will save them some stress at some point in their career.

I put one in for a debridement on a homeless guy who said he was npo and he started blowing chunks and aspirated. Seriously regretted that one.
 
I try to impress upon them that, when about the NPO question, YOU LIE, YOU DIE! And I tell them something like that at least twice during the interview (at the beginning and in the end).
 
Supraglottic-airways-used-for-pediatric-airway-management-A-Size-2-I-gel-TM-B-Size_Q640.jpg


The option to do an LMA also depends heavily on the kind of LMA. If you are using an igel (pictured left) with an integral bite block, gastroport, and perfect seating then you can do a lot more for a lot longer (still would stay under 4-5 hrs).

If you have one of the cheaper kinds, and you have any kind of hesitation, then tube 100% of the time. Ultimately at the end of the anesthetic you want to have




tenor.gif
 
Lazy is good. Sometimes the best thing for the patient is not doing anything.
Laws of the House of God
GOMERS don't die.
GOMERS go to ground.
At a cardiac arrest, the first procedure is to take your own pulse.
The patient is the one with the disease.
Placement comes first.
There is no body cavity that cannot be reached with a #14G needle and a good strong arm.
Age + BUN = Lasix dose.
They can always hurt you more.
The only good admission is a dead admission.
If you don't take a temperature, you can't find a fever.
Show me a BMS (Best Medical Student, a student at The Best Medical School) who only triples my work and I will kiss his feet.
If the radiology resident and the medical student both see a lesion on the chest x-ray, there can be no lesion there.
The delivery of good medical care is to do as much nothing as possible.
 
I would, and have done it. The alternative would have been a difficult intubation for a cysto. It's all a matter of risks vs benefits.

How many obese (or diabetic) NPO patients have you seen with residual solid food (not just particles) on an EGD? I have seen just one, and that applies to many hundreds of patients.
it helps that i have a lot of frequent fliers, but i use lmas in fatties all the time, like 300+ers in lithotomy. 90% of LMA issues i have seen in all pt populations is when the pt gets light.
 
At least you can properly recruit one or two errant alveoli if there's an ett in place.

I don't find that necessary with a properly placed lma with some pressure support.
 
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I put one in for a debridement on a homeless guy who said he was npo and he started blowing chunks and aspirated. Seriously regretted that one.

That is not on you if you asked about npo status and not an emergent case. I place an lma 100% of the time for debridements if they are npo (or said they were npo) and not an emergency.
 
As per the original question, I do a fair amount of triple atrhodesis/ total ankle replacements/ ankle poly exchanges and I ALWAYS use an LMA unless it doesn't fit well.

These cases can be 3-4+ depending on complexity and I have never had an issue. I like SV because it gives me a clue as to how well my blocks are working and tourniquet pain.

I honestly think the 2 hour rule is academic dogma as well as using paralysis with lma's.
 
As per the original question, I do a fair amount of triple atrhodesis/ total ankle replacements/ ankle poly exchanges and I ALWAYS use an LMA unless it doesn't fit well.

These cases can be 3-4+ depending on complexity and I have never had an issue. I like SV because it gives me a clue as to how well my blocks are working and tourniquet pain.

I honestly think the 2 hour rule is academic dogma as well as using paralysis with lma's.

Same. I paralyze with lmas sometimes, no issues. Have used mechanical ventilation with lmas, no issues. I have had the igel not sit right a few times and had to tube the patient but only 3 or so times. I have noticed that if I stick it in too early, the tv volumes suck until the patient is deep enough.
 
Same. I paralyze with lmas sometimes, no issues. Have used mechanical ventilation with lmas, no issues. I have had the igel not sit right a few times and had to tube the patient but only 3 or so times. I have noticed that if I stick it in too early, the tv volumes suck until the patient is deep enough.
The i-gel LMA takes a while to warm up and mold to the patient's pharynx, so not having leaks, right after placement, can be a sign of a big-time future sore throat.
 
As a new attending with majority pediatric population, it has to be a straightforward procedure (<2 hrs if not orthopedic with a block). Most of the call assist/ rapid response to a room in my institution usually involves an LMA with a resident/crna. Rather be over cautious.
And if less than 1 year old; ETT
 
Case longer than 1hr of controlled ventilation: ett
Shorter, unless GI procedure past a gastroscopy, need for NMB, or laparoscopy: lma. Unless obvious contraindications.

If spontaneous, lma most days, ett if we're feeling adventurous. MAC 1.3 with a tube behaves much the same as with an lma.
 
What’s the most you had to give a patient for Lma induction ? Had a case today 60 yo 100 kg male patient no pmh had to give 2 versed 100lido and 400 of propofol. The propofol was in divided doses. In hindsight would of given fentanyl or gas. Wondering if patient was on my or heavy drinker. Vitals barely budged and he still reacted a little bit when I placed.
 
Yup. Not everyone needs to be at 1.3 or even 1(obviously), but the way I was taught (by old nurse anesthetists and anesthesiologists) was to set the sevo at 1.5-2%, ventilator on spont/bag or pressure support, then let the patient dictate how deep they need to be through tidal volumes and respiratory rates (initially high, usually lower towards the end of surgery). Usually no real need for high doses of repeat opioids,save from induction drugs, and saves on noradrenaline/phenylephrine.

Saves a lot of fentanyl (not really a cost issue, granted), though, and emergence is a non issue. If sleepy afterwards, the patient can keep the LMA until they're awake enough to remove it themselves in postop.

80-85% of my cases are done with an LMA, most of these patients are any combination of old, frail, sick or fat. Usually lithotripsies with or without laser, ureter stents, bladder and prostate resections.

Someone in this thread mentioned NMB with an LMA in place. I do it several times a week(mid case, 99% of times with mivacurium, since we're too cheap to pour sugammadex at our patients) , but really hate it with Uniques, since any tone keeping a tight seal disappears, and airway leaks go way beyond what constitutes a safe working environment. Igels are a little better, I find, but if I know with some certainty the surgery involves areas close to the obturator nerve, I like to save myself the hassle, talk to my attending and just prop/roc/tube.

A pro tip I find helpful for these cases, if an LMA and spontaneous ventilation for whatever reason really is preferred, I'm simply very generously lubing the backside of the LMA, seems to help with lowering airway leaks. Also helps with LMAs (uniques, at least) in the GI room.

Mac 1.3? Are you a CRNA? Most of my patients are around 0.6.
 
What’s the most you had to give a patient for Lma induction ? Had a case today 60 yo 100 kg male patient no pmh had to give 2 versed 100lido and 400 of propofol. The propofol was in divided doses. In hindsight would of given fentanyl or gas. Wondering if patient was on my or heavy drinker. Vitals barely budged and he still reacted a little bit when I placed.
600mg. Started with 400 and when he wasn't deep enough have another 200. Big college football player. Never went apneic. Still had some fight in him putting the LMA in.
 
am i being overly cautious that i'm still intubating mostly everyone now? covid is pretty bad in my neck of the woods... even with negative testing of everyone...i don't know if i trust them.
 
am i being overly cautious that i'm still intubating mostly everyone now? covid is pretty bad in my neck of the woods... even with negative testing of everyone...i don't know if i trust them.

Covid is bad in every neck of the woods...I try my best to not tube people. If I do, no bagging. Spinals/local/blocks and propofol for everyone I can. No facemask if I can avoid it (also saves on plastic although some of the pacu nurses seem to be hell bent on placing supplemental o2). I leave their cloth mask on.
 
So if a patient breaths spontaneously, with a glorified oral airway in their mouth, for 5 hours, it's too long? Darn, what's your cutoff for propofol MAC cases (e.g. podiatry)? How about life and spontaneous ventilation, in general? 😛

On the serious side, as long as I have a channel to suction the stomach, and as long as the cuff is adjustable (lower risk of tissue injury and better individual fit), I have done 4-5 hour cases, even with muscle-relaxation and controlled ventilation. Obviously, it also depends on the patient.
The other day,
I had 25 years old Emergency Case, but 6 hours NPO with huge flap scalp wound requires suturing, and I put i-Gel and spontaneous NOT controlled ventilation and the operation lasts an hour and a half.
I put the bed - reversed trendelenburg and I covered the maintenance with Isoflurane, and multimodal analgesia like Paracetamol + remifentanil boluses (20 mcg each and slowly) and even drip it the dose !
I wasn't happy with i-Gel, the problem was behind i-Gel him not tube him, he was very heavy smoker ! !
I am still questioning this case, and everything went well, and he woke up like a charm ! !
Did I do the right thing?
What do you think ?
 
Asked myself the same question when I started. Usually 3 hours or 4 hours max. Major issues as far as I know are lingual nerve palsy, increased aspiration risk for a prolonged case, and increased pressure support requirements over time. My BMI cutoff is usually around 40 and in those cases <2 hours
Thanks for such explanation, I have questions :
- Per hour time, how many ml does the gastric mucosa produce? especially if we consider the surgery is a stress and yet we give analgesia ,,, ect
- In elective surgeries with fasting - like 8 hours - did they measure how much gastric volume of mucous (vs acid if any) in ml stayed in the stomach, I think this is a silly question, but always had it in my mind !
- Do you prefer Pressure or Volume controlled mode in Supraglottic devices whatever the type like LMA or i-Gel?
- How long acceptable for spontaneous breathing the patient has to stay on i-Gel vs LMA ? (spontaneous?)
Thanks for answering !
 
There’s no black and white answer. So many factors that go into decision.
1- patient factor
2- type of surgery
3- Rapport with surgeon
4- relative ease of access to airway

You use the combo of these to figure out the plan. I’ve done Cases for 4 hours under SV via LMA. PPV, i limit it unless I have to. I have easily placed at least thousand LMAs without incident . I’ve done obese patients in beach chair and lithotomy via LMA for several hours. i’ve never had a problem. It’s not a
magic wand but it limits airway manipulation and I feel faster wake ups .

Use all the tools you have and use what works for you.
 
The other day,
I had 25 years old Emergency Case, but 6 hours NPO with huge flap scalp wound requires suturing, and I put i-Gel and spontaneous NOT controlled ventilation and the operation lasts an hour and a half.
I put the bed - reversed trendelenburg and I covered the maintenance with Isoflurane, and multimodal analgesia like Paracetamol + remifentanil boluses (20 mcg each and slowly) and even drip it the dose !
I wasn't happy with i-Gel, the problem was behind i-Gel him not tube him, he was very heavy smoker ! !
I am still questioning this case, and everything went well, and he woke up like a charm ! !
Did I do the right thing?
What do you think ?
I personally would have never put an LMA in that one, for 3 reasons:
1. One cannot count on NPO when the patient gets opiates for pain (they slow down gastric evacuation, also the trauma itself does). Also, I don't trust emergency patients for NPO purposes (people lie, especially youngsters, sometimes even when told that lying can kill them).
2. It's a scalp wound. In the US, that means that the OR table is turned away from me. Unless my LMA fits perfectly, I tend to just insert a tube; it's harder to dislodge.
3. Liability in case of aspiration, in the US.

Truth be told, if concerned about airway/lungs/intubation, I would have negotiated with the surgeon to use plenty of local anesthetic with some lighter sedation (e.g. low-dose propofol infusion) that maintained his airway reflexes but kept him snoring. Being a nervous 25 year-old, I am sure he's not that cooperative or easy to sedate, especially for solo residents, so don't feel bad if it didn't cross your mind. This is also very surgeon-dependent; some are just too lazy to use enough local (it's not rocket science for suturing, it's a field block).

Next time you have a smoker, don't worry about it, just be prepared for a ton of secretions, mucus plugging and coughing. Sometimes stuff like glycopyrrolate helps dry up the secretions (or at least the saliva).

Also, remember that remifentanil not only goes away when the infusion is stopped, but it's also one of the medications that can cause a paradoxical hyperalgesia.

Again, there are many ways to do the same thing in anesthesia. It's all a matter of risks vs benefits. One could even do it just with rare boluses of low-dose ketamine for pain AND sedation (not the best idea in a heavy smoker), for example; or just with local anesthetic (I know a person who had an open appendectomy like that, in a developing country). It depends on the patient, the surgeon and YOU.

It sounds like you have already taught yourself the lesson here: when in doubt, just tube them.
 
I personally would have never put an LMA in that one, for 3 reasons:
1. One cannot count on NPO when the patient gets opiates for pain (they slow down gastric evacuation, also the trauma itself does). Also, I don't trust emergency patients for NPO purposes (people lie, especially youngsters, sometimes even when told that lying can kill them).
2. It's a scalp wound. In the US, that means that the OR table is turned away from me. Unless my LMA fits perfectly, I tend to just insert a tube; it's harder to dislodge.
3. Liability in case of aspiration, in the US.

Truth be told, if concerned about airway/lungs/intubation, I would have negotiated with the surgeon to use plenty of local anesthetic with some lighter sedation (e.g. low-dose propofol infusion) that maintained his airway reflexes but kept him snoring. Being a nervous 25 year-old, I am sure he's not that cooperative or easy to sedate, especially for solo residents, so don't feel bad if it didn't cross your mind. This is also very surgeon-dependent; some are just too lazy to use enough local (it's not rocket science for suturing, it's a field block).

Next time you have a smoker, don't worry about it, just be prepared for a ton of secretions, mucus plugging and coughing. Sometimes stuff like glycopyrrolate helps dry up the secretions (or at least the saliva).

Also, remember that remifentanil not only goes away when the infusion is stopped, but it's also one of the medications that can cause a paradoxical hyperalgesia.

Again, there are many ways to do the same thing in anesthesia. It's all a matter of risks vs benefits. One could even do it just with rare boluses of low-dose ketamine for pain AND sedation (not the best idea in a heavy smoker), for example; or just with local anesthetic (I know a person who had an open appendectomy like that, in a developing country). It depends on the patient, the surgeon and YOU.

It sounds like you have already taught yourself the lesson here: when in doubt, just tube them.
Many Thanks Dr FFP, I got your pearls
I wasn't happy of this i-Gel and although, the patient was in the ER for many hours NPO and got a detailed history, and YES I should put an ETT, but you know the Neurosurgeon said "It won't take less than 30 minutes", and I believed him, so I thought of less complicated i-Gel vs ETT, and the remifent I used (I only had 100 mcg handy)!
I used Ketamine and Propofol, and let the patient goes deep, and a bolus of remifent and then inserted a fitted i-gel and it worked Okay, but the RR was an issue like mid 20s to upper 20s !
Then the Op went well, and when I woke up the patient, he was talking with ease and didn't recall too, and I visited him later, he was fine too !

So, this thread is important, I learned from you about using LMA for longer operation time, as in Books it said less than an hour, but you and others went further and not fearing the Aspiration risk, and for me I concerned about the work of breathing if the patient left on spontaneous but for how long?

Many thanks !
 
Many Thanks Dr FFP, I got your pearls
I wasn't happy of this i-Gel and although, the patient was in the ER for many hours NPO and got a detailed history, and YES I should put an ETT, but you know the Neurosurgeon said "It won't take less than 30 minutes", and I believed him, so I thought of less complicated i-Gel vs ETT, and the remifent I used (I only had 100 mcg handy)!
I used Ketamine and Propofol, and let the patient goes deep, and a bolus of remifent and then inserted a fitted i-gel and it worked Okay, but the RR was an issue like mid 20s to upper 20s !
Then the Op went well, and when I woke up the patient, he was talking with ease and didn't recall too, and I visited him later, he was fine too !

So, this thread is important, I learned from you about using LMA for longer operation time, as in Books it said less than an hour, but you and others went further and not fearing the Aspiration risk, and for me I concerned about the work of breathing if the patient left on spontaneous but for how long?

Many thanks !
Everybody makes mistakes. Some of us actually learn from them; it's called "experience". It's a good sign that you cared enough to have an uneasy feeling during the case.

What we said in this thread applies for elective cases, not emergent ones. Most American anesthesiologists would think very carefully before using an LMA in an emergent case. I would, if I had a well-known fast surgeon, if the case were very short, and if I felt the patient was trustworthy enough (and usually after long NPO times, e.g. somebody who had only had a coffee in the morning before coming to the emergency room), or if the risks of intubation exceeded its benefits, or the risks of its alternatives (e.g. difficult airway).

You have an advantage for training in a country with low malpractice risk; every coin has two sides.
 
Along the same line, what is everyone's BMI cut off? I used to be very conservative and tube anyone over 35 but now have extended that to 40 assuming no history of DM. I was shocked however when I walked into my colleagues room and she had a patient with a BMI of 55 that she just threw in an LMA for.
 
Along the same line, what is everyone's BMI cut off? I used to be very conservative and tube anyone over 35 but now have extended that to 40 assuming no history of DM. I was shocked however when I walked into my colleagues room and she had a patient with a BMI of 55 that she just threw in an LMA for.
Me too. And it ended up being a code situation. She was blue w sats in the 40s.
Not a good idea. With all that abdominal girth in a flat position, there has got to be some reflux happening.
 
Agree with above, risks vs benefits, never clear cut and dry. I always had an attending tell me in residency "LMAs are for lazy anesthesiologists". You have to ask yourself what is the benefit to putting in an LMA vs a tube. When it boils down to it, there isn't many benefits. The decreased sore throat never convinced me, maybe less hoarseness. I would add I don't put LMAs in patients when the positioning is high lithotomy regardless of BMI.

I disagree with your attending.

Advantages:
1) Not requiring neuromuscular blockers precludes possibility of anaphylaxis/anaphylactoid reactions, all the adverse effects of succinylcholine if used, weakness at case end, taking away a patient's ability to spontaneously ventilate, risk of hypoxia if you are unable to intubate or ventilate after NMB administration, requirement to reverse, or side effects from neostigmine, glycopyrrolate or suggamadex and finally cost to the patient and/or overhead for a surgery center.

2) Not performing laryngoscopy may preclude the risk of dental or oropharyngeal trauma, granted it's low risk in skilled hands; damage to vocal cords; oropharyngeal pain post-op; administration of narcotics to blunt the response to laryngoscopy

I think it's a useful skill to be flexible yet safe, rather than practice completely in absolutes. The only absolutes I subscribe to is avoid hypoxia, severe hypotension... and maybe intraop awareness.
 
Someone in this thread mentioned NMB with an LMA in place. I do it several times a week(mid case, 99% of times with mivacurium, since we're too cheap to pour sugammadex at our patients) , but really hate it with Uniques, since any tone keeping a tight seal disappears, and airway leaks go way beyond what constitutes a safe working environment. Igels are a little better, I find, but if I know with some certainty the surgery involves areas close to the obturator nerve, I like to save myself the hassle, talk to my attending and just prop/roc/tube.

TIL, mivacurium is available again in the US (had to wikipedia that one).
 
Along the same line, what is everyone's BMI cut off? I used to be very conservative and tube anyone over 35 but now have extended that to 40 assuming no history of DM. I was shocked however when I walked into my colleagues room and she had a patient with a BMI of 55 that she just threw in an LMA for.

Sometimes these patients are very "pear shaped" - all their weight is in their buttocks/hips/legs; BMI wouldn't really mean that much.

I don't have a cutoff BMI for an LMA. I like to see how they breathe with a mask strapped on - adequate or huge Vt's is always a good sign that they'll continue to breathe well with an LMA after placement.
 
Everybody makes mistakes. Some of us actually learn from them; it's called "experience". It's a good sign that you cared enough to have an uneasy feeling during the case.

What we said in this thread applies for elective cases, not emergent ones. Most American anesthesiologists would think very carefully before using an LMA in an emergent case. I would, if I had a well-known fast surgeon, if the case were very short, and if I felt the patient was trustworthy enough (and usually after long NPO times, e.g. somebody who had only had a coffee in the morning before coming to the emergency room), or if the risks of intubation exceeded its benefits, or the risks of its alternatives (e.g. difficult airway).

You have an advantage for training in a country with low malpractice risk; every coin has two sides.
Unfortunately, the malpractice is of a huge concern on the level of Tribes vs Law, the Tribe would charge the physician for malpractice and it happened all the time (especially after 2003 - the word is for Tribes first not Law), and I recall our brilliant Anesthesiologist got caught with Malignant Hyperthermia case at a private hospital - young 20s female for tonsillectomy and the patient died, because we don't have dantrolene unfortunately, they charged him with like 15 thousand dollars and the ENT surgeon with the same, the whole was over 30K US$, and this is after negotiation from 100K like down to 30K after both doctors tribes sat with the patient's tribe and bring another well known figures to judge !
It is what it is Dr FFP
That case was an example, the physician in Iraq is always haunted by Tribes and the Law is also taking its place, it is not like what you are thinking of a developing Country like Iraq - it is beyond; Tribes can ruin our lives, no Law and although we might living a civil life but can't deny the rule of Tribes especially in the mid and south of the Country!
 
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