results : Effect of Cricoid Pressure Compared With a Sham Procedure in the Rapid Sequence Induction of Anesthesia. JAMA Surg. 2019

Jul 21, 2018
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Hello everyone,

Anyone that read the article would care to share their opinion ? Cricoid Pressure Compared With a Sham Procedure in Rapid Sequence Induction of Anesthesia

I am having a hard time understanding the meaning of the result of the study

" This large randomized clinical trial performed in patients undergoing anesthesia with RSI failed to demonstrate the noninferiority of the sham procedure in preventing pulmonary aspiration"?

Are the results saying that the sham procedure (no cricoid pressure) are inferior when compared to cricoid pressure, therefore the sham procedure has an increase risk of pulmonary aspiration during RSI vs cricoid pressure ?
 

NoodleIncident

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“Noninferiority” means that the sham procedure was not worse than cricoid pressure in preventing aspiration. The hypothesis was that the sham procedure would allow for more aspiration, but this was not found to be the case. Haven’t read the article, just going by the little excerpt you posted.
 
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DM27

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These two parts from the study are slightly more helpful:

"The primary end point, pulmonary aspiration, occurred in 10 patients (0.6%) in the Sellick group and in 9 patients (0.5%) in the sham group. The upper limit of the 1-sided 95% CI of relative risk was 2.00, exceeding 1.50, failing to demonstrate noninferiority (P = .14). "

"his large, randomized double-blind trial in patients undergoing anesthesia with RSI failed to demonstrate the noninferiority (δ = 50%) of the sham procedure as compared with the cricoid pressure in preventing pulmonary aspiration. We also observed a low incidence of pulmonary aspiration (0.5%), and we did not observe any significant secondary end points except those suggesting a more difficult tracheal intubation in the Sellick group. "

One odd thing about the study is they expected an aspiration rate of 2.8% in this high-risk inclusion group and used this to power their recruitment.

The inclusion criteria were patients 18 years and older with a full stomach (<6 hours fasting) or the presence of at least 1 risk factor for pulmonary aspiration (emergency conditions, body mass index >30 [calculated as weight in kilograms divided by height in meters squared], previous gastric surgery [sleeve, bypass, or gastrectomy], ileus, early [<48 hours] postpartum, diabetic gastroparesia, gastroesophageal reflux, hiatus hernia, preoperative nausea/vomiting, and pain). "

Especially taking the BMI >30 or GERD (this would represent probably 3/4 of the patients I deal with) as a way to include someone as "high-risk" the 2.8% aspiration rate is FAR higher than I would ever expect, I would be essentially having someone grossly aspirate 1-2 times a month. The 0.5% rate they found seems more reasonable and would have ballooned the amount of people they had to recruit.
 
OP
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Jul 21, 2018
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Just to clarify the wording is really making it super confused, although I understand some of the responses posted above I am having a hard time in connecting the dots for this specific study.

Hypothesis:
"This multicenter, noninferiority randomized clinical trial was conducted to test the hypothesis that the incidence of pulmonary aspiration is not increased when cricoid pressure is not performed during a RSI of anesthesia"

Results:
"This large randomized clinical trial performed in patients undergoing anesthesia with RSI failed to demonstrate the noninferiority of the sham procedure in preventing pulmonary aspiration."

So this results means that sham procedure "failed" in non-inferioty, meaning if it failed in been "non inferior" to cricoid pressure ?

So if it failed means there were an increase in pulmonary aspiration with the sham procedure vs cricoid pressure ?

or , *statistically* this study was not able to show that the sham procedure was "as good as" cricoid pressure?

So lets suppose if the the study did NOT fail the non inferiority test, therefore the sham procedure would not have increased pulmonary aspiration cases ?

Thanks for all the responses.
 
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nimbus

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I never had the sense that it did anything. Anatomic studies show the esophagus is often laterally displaced and/or inferior to the cricoid cartilage. Maybe a neck tourniquet....
 
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NoodleIncident

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“Failed to demonstrate the non-inferiority of the sham procedure” means that it failed to show that the sham procedure had a higher rate of aspiration than cricoid. Stated differently, they failed to show that the sham was any worse in preventing aspiration than cricoid. They set out to show that the sham procedure was worse in regard to aspiration, but could not.

If it DID NOT fail to show non-inferiority, then this would mean that if showed inferiority (double negative), meaning that the sham allowed for more aspiration than cricoid.
 
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dchz

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I never had the sense that it did anything. Anatomic studies show the esophagus is often laterally displaced and/or inferior to the cricoid cartilage. Maybe a neck tourniquet....
Didn't work for Robin Williams.

or did it?
 

caligas

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Having some poorly trained person jamming their arms and sausage fingers in your face to give crappy cricoid pressure has always seemed of questionable value to me.

reverse trendlenberg, fast push of sux, quick intubation by skilled person are all better
 

ethilo

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I read this conclusion as: They demonstrate that cricoid reduces pulm aspiration better than sham does, albeit by a very small percentage difference, but it results in more time and difficulty with tracheal intubation.

I personally prefer no cricoid pressure, it adds too much activity up near the head and neck. Really good patient positioning goes a very long way. I think keeping it simple is better for me.
 

FFP

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Cricoid pressure is not as important, by far, as proper positioning and proper muscle-relaxation (before stimulating the patient).
 

dr doze

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Cricoid pressure is not as important, by far, as proper positioning and proper muscle-relaxation (before stimulating the patient).
Agree, but how many anesthesiologists when asked would say that it is below the standard of care NOT to apply cricoid in the following scenario: known or suspected full stomach, reverse Tberg, no mask ventilation/stimulation, 2+mg/kg of sux--->aspiration?
 
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FFP

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Agree, but how many anesthesiologists when asked would say that it is below the standard of care NOT to apply cricoid in the following scenario: known or suspected full stomach, reverse Tberg, no mask ventilation/stimulation, 2+mg/kg of sux--->aspiration?
That's because doctors are among the best and brightest in this country.
 
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Globulinus

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Best summary on this topic I have ever heard:
As far as best and brightest...
I was called by president of the group:
- we have a problem with people complaining about you.
-????
- you are not applying CP during RSI. They feel uncomfortable. Its not how we practice here.
(People are bunch of AA, CRNAs and (!!) OR nurses)
- but there is plethora of literature that CP actually make intubation more difficult and, potentially, increase risk of aspiration..
(showing him articles, my presentation on this topic, data, standards of practive from different countries, offering to make presentation to whole department...)
- No! We don't practice like it. I did CP all my life and didn't have aspiration.
- ........(luckily, i kept my mouth shut:))

Looking around for a new gig now ,since working with grossly incompletent and ignorant ppl is paaaaainful....
 

anbuitachi

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Best summary on this topic I have ever heard:
As far as best and brightest...
I was called by president of the group:
- we have a problem with people complaining about you.
-????
- you are not applying CP during RSI. They feel uncomfortable. Its not how we practice here.
(People are bunch of AA, CRNAs and (!!) OR nurses)
- but there is plethora of literature that CP actually make intubation more difficult and, potentially, increase risk of aspiration..
(showing him articles, my presentation on this topic, data, standards of practive from different countries, offering to make presentation to whole department...)
- No! We don't practice like it. I did CP all my life and didn't have aspiration.
- ........(luckily, i kept my mouth shut:))

Looking around for a new gig now ,since working with grossly incompletent and ignorant ppl is paaaaainful....
i just have myself or someone else rest fingers there... who actually applies the specified # of newtons anyway.

i never do reverse T berg for full stomach patients..
 

0kazak1

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Yeah 20-40N of pressure is a lot more than most realize. Imaging having a 2L bottle of soda with the cap sitting on your neck. That’s less than 20N of force.
 

BLADEMDA

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Best summary on this topic I have ever heard:
As far as best and brightest...
I was called by president of the group:
- we have a problem with people complaining about you.
-????
- you are not applying CP during RSI. They feel uncomfortable. Its not how we practice here.
(People are bunch of AA, CRNAs and (!!) OR nurses)
- but there is plethora of literature that CP actually make intubation more difficult and, potentially, increase risk of aspiration..
(showing him articles, my presentation on this topic, data, standards of practive from different countries, offering to make presentation to whole department...)
- No! We don't practice like it. I did CP all my life and didn't have aspiration.
- ........(luckily, i kept my mouth shut:))

Looking around for a new gig now ,since working with grossly incompletent and ignorant ppl is paaaaainful....
Aspiration risk is directly related to the type of practice you are in and the type of patients. If you do trauma there will be many aspirations. If you do full stomachs and bowel obstructions then aspirations likely to occur (rare but they occur).

Or, if your patients lie and aspirate their breakfast through the LMA you will see it as well.

Many have never seen MH either. Or countless other issues/disease etc in their careers. Those of us who have seen this and much more know your boss is an idiot. That said, why not just appease him and do cricoid pressure with 3-5 Newtons of force which is what most use anyway.

In life you need to pick your battles if you wish to stay employed or married.
 

Globulinus

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That's, basically, exaclty what I decided to do at that moment :)
Last straw that broke my back was another complaint from AA, which resulted in another conversation with boss:
- I have heard that you are giving sux to pts while putting LMA. Its gross malpractice! Midlevels complaining about it.
- Yes, I do give 10-20 mg of sux. There are plenty of literature that supports it. Its safe and facilities insertion, especially 2nd generation LMAs...(again, offering present literature for the whole department, have a discussion, etc.)
- No. We don't do it here. You must change your practice!

I kept my mouth shut again, although it was hard. :/
I've decided that rather go back to academia or locums then practicing AA style anesthesia in PP....
Agreed about battles, life is a bitch :)

As far as how much force to apply...
there is a nice study from Japan, where they tought RN to apply 30-40 N on manekens.
Took about 2 weeks to get to 80% correctness.
They tested same RNs some time later and found that only around 15-25% kept the skill 3 weeks later...
Classic use it or loose it scenario.
 
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BLADEMDA

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I use sux from time to time after placing an LMA. 20-30
Mg iv x 1. That said, most of the time I don’t need any relaxant to place the LMA or to facilitate ventilation.

I would adopt my approach and pacify your boss. You will only use sux to facilitate ventilation if needed from time to time. Some just mask the patient with Sevo but I do find sux to be faster and more efficacious.

Again, split the baby and move on.
 
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fakin' the funk

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Cricoid pressure is not as important, by far, as proper positioning and proper muscle-relaxation (before stimulating the patient).
Yes, goddammit, YES!

Assess risk - is the patient in the 99% that either never regurgitate or aspirate or are healthy enough to do fine even if they do, OR, are they the 1%? Don't let them cough and regurgitate up their junk and they won't aspirate it. Good NMB. No test ventilating as a rule, obviously no "modified" RSI - either it's RSI or it's Slow Sequence Induction.
 
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AdmiralChz

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Until it’s not considered “standard of care” and not doing it could hold you liable, I’ll continue going through the motions with RSI. My more senior partners that do litigation consulting say stuff like this is always coming up and way too easy to pick apart. Other examples - not using ultrasound or stimulation for blocks, no 2 provider signatures for opiate waste, or using a ventilator that continuously fails check off.

All of us in our specialty should know how much garbage “non-inferiority” studies are.
 

nimbus

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Until it’s not considered “standard of care” and not doing it could hold you liable, I’ll continue going through the motions with RSI. My more senior partners that do litigation consulting say stuff like this is always coming up and way too easy to pick apart. Other examples - not using ultrasound or stimulation for blocks, no 2 provider signatures for opiate waste, or using a ventilator that continuously fails check off.

All of us in our specialty should know how much garbage “non-inferiority” studies are.
I do it too to cover my own ass. But I have no illusion that cricoid pressure is helping my patient.
 

FFP

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caligas

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I use 10-20 mg of sux in EVERY laryngospasm, even in awake patients (been there, done that). So anybody who says that dose paralyzes patients is an idiot.

I can't imagine how it wouldn't help in an LMA insertion with zero side effects. I even give roc to my LMAs if needed (not for insertion though).
prop-roc-LMA, baby.
 
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BLADEMDA

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I don’t need any muscle relaxants for the vast majority of my LMA cases. I’ve been inserting LMAs for decades and see no reason to start using Sux or Roc routinely. But, if I have difficulty ventilating the patient or obvious laryngospasm then a little sux goes a long way to facilitating the process.

How do I feel about those who want to use sux on every case? I think it’s unnecessary and I don’t like giving meds that aren’t needed.
 

interscalene

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I will use sux to help facilitate Lma placement or in a laryngospasm situation but if i anticipate i am gonna need roc ; i was trained to tube all the way . I try to avoid ppv through an lma unless transient
 

nimbus

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I have no problem giving roc and using PPV with an lma. The typical scenario this comes up is when I’m doing an umbilical hernia repair with an LMA and the belly is moving too much with respiration. I just give 30-40 of roc and turn on the vent. I haven’t used sux at all in 3-4 years.