Very cool fact

[jetproppilot]

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Here's a fact that is relevant on so many levels, yet I'm gonna apply SAID FACT (based on my expansive physiology knowledge 🙂laugh🙂 to

one group:

ANXIETY-RIDDEN FIRST YEAR ANESTHESIA RESIDENTS that feel Under The Gun To Hurry Their Intubation Since Dude May Die From Hypoxemia If I Take Too Long.

(they won't....the moral of This Story is to teach you to Use Physiology To Your Benefit)

CASE IN POINT:

You've got your normal case as a CA-1: A laparoscopic gallbladder or a hysterectomy or a ureteral stone removal... OK OK OK you're prepared since you're not a SLACKER

Patient in the OR, monitors on, you RECHECK your setup and all is good so you proceed with your induction consisting of

1) 10 mg rocuronium defasciculating dose (make sure you give it followed quickly by induction so your patient doesn't experience that "weak" feeling)

2) Propofol 150mg (with a delta of 50mg depending on your interpretation of the patient's Dose Response Curve, which you can easily figure out (very important interpretation...someone please call me out on this topic later on a New Thread)

3) Succinylcholine

4) Now you are mask ventilating the patient

5) INTUBATION. SOMETHING YOU

HAVE TO BECOME A

ROKKSTARR AT IF YOU WANNA BE AN

ANESTHESIOLOGIST....

WUH OH

you're having problems with the intubation as a

NEW ANESTHESIA RESIDENT

which we've all had but you're in the moment and you're trying to Sweep The Tongue but it's not working so you TRY AGAIN with the same result but this time your technique is a little better at which point (probably 60 seconds later) you look at your Attending for help instead of trying again since you're CONVINCED you're about to

KILL THIS DUDE FROM HYPOXEMIA

No man.

Actually, if it's a healthy patient who's been preoxygenated,

GO AHEAD AND LEAVE TO TAKE A

QUICK WHIZZ THEN COME BACK

The O2 sat is still gonna be ok.

Dear Early Anesthesia Residents,

Think about the physiology contributing to the scenerio I posted, assuming you were putting to sleep a Healthy Young Person that you preoxygenated.

HOW MUCH TIME DO YOU THINK WILL ELAPSE BEFORE THE PATIENT DESATURATES?

In order to answer this question you need to recall some pulmonary function knowledge and recall how much oxygen is needed per minute to maintain bodily functions.

I'm gonna rephrase the question for simplicity purposes:

"I'm in the operating room and my patient is on the table, monitors on, everything is copasthetic. I place the oxygen mask (FiO2=1.0) on this healthy person's face with a good seal and the patient Breathes Deeply In And Out for a good

thirty seconds.

I induce and intubate but I forget to hook up the patient to the circuit.

"OH S H IT," I say to myself, "I'VE GOTTA TAKE A WHIZZ BEFORE THIS CASE."

(DISCLAIMER: This would NEVER HAPPEN. )

I leave the freshly preoxygenated, paralyzed, intubated patient that is NOT hooked up to the anesthesia machine circuit

to take a whiz.

HOW MUCH TIME DO I HAVE TO LEAVE

TAKE A WHIZ

AND RETURN

LIKE NOTHING HAPPENED?

(the answer will ASTOUND you)

 

[Silent Cool]

JPP is one of my favorite SDNers. ROKKSTAR post. As per usual.

 

[VentdependenT]

Think about a lung volume parameter and O2 consumption per min 🙂

excellent post

 

[WholeLottaGame7]

I try to teach this to any med students/interns rotating through the OR with me. Of course, knowing it doesn't really help their anxiety all that much 🙂

 

[herkyMD]

how much does the patient weigh?

 

[Gern Blansten]

I leave the freshly preoxygenated, paralyzed, intubated patient that is NOT hooked up to the anesthesia machine circuit

to take a whiz.

HOW MUCH TIME DO I HAVE TO LEAVE

TAKE A WHIZ

AND RETURN

LIKE NOTHING HAPPENED?

(the answer will ASTOUND you)

We cannot know how long it will take you without knowing the status of your prostate. I've heard it takes some guys 8 or 9 minutes.

 

[AnesThrow]

We cannot know how long it will take you without knowing the status of your prostate. I've heard it takes some guys 8 or 9 minutes.

👍



As a medical student, if I didn't sweep the tongue correctly on my first try, the attending would usually take over and then let me intubate after the blade was positioned correctly.

 

[jetproppilot]

We cannot know how long it will take you without knowing the status of your prostate. I've heard it takes some guys 8 or 9 minutes.

ASSUME I"VE GOT A STREAM REPRESENTING THE HORSE YOU BET ON LAST WEEK AT THE TRACK (that's roughly TWO MINUTES OF THE STRONGEST PISS I'VE EVER SEEN LOL)

And the Patient Dude is a

SIX FOOT THREE

235 POUND (106 kg)

INSIDE LINEBACKER FROM

THE U.😀

 

[jetproppilot]

think about a lung volume parameter and o2 consumption per min 🙂

excellent post

venty,

shhhhhhhhhhhhhhhhhhhhhhhh!!!!

 

[herkyMD]

So I'm just a lowly M3 hoping one day to become an anesthesia rokkstar so if I'm way off on this, please set me straight. I seem to remember from my anesthesia rotation that VO2 is roughly 6-10 ml/kg/min. So 106 kilo dude's VO2max would be 600-1000 ml/min. FRC is about 2.5 L in most people. So you're looking at ~2.5-4 mins before your patient desats completely??

 

[anes]

Vo2 more like 3 ml/kg/min.... 6-10 would be pediatric.... He likely has 8 minutes or so.

 

[herkyMD]

Vo2 more like 3 ml/kg/min.... 6-10 would be pediatric.... He likely has 8 minutes or so.

Thanks for clearing that up, anes. I think I heard those numbers while doing a peds case. Good info to know.

 

[pgg]

So I'm just a lowly M3 hoping one day to become an anesthesia rokkstar so if I'm way off on this, please set me straight. I seem to remember from my anesthesia rotation that VO2 is roughly 6-10 ml/kg/min. So 106 kilo dude's VO2max would be 600-1000 ml/min. FRC is about 2.5 L in most people. So you're looking at ~2.5-4 mins before your patient desats completely??

6-10 is high for adults. O2 consumption is more like 3cc/kg/min in adults. Up to 5-6 in kids.

Sometimes when I'm bored I look at the vent and mentally (insp O2 - exp O2) x minute ventilation ... it's nearly always very close to those numbers. Uncanny-like close.

 

[caligas]

A Recent left lower lobectomy turned into pneumonectomy and I had to pull back my double lumen and do apnea whie surgeon closed the bronchus. Took about 7 min to close. No breaths. Lowest sat was 91.

 

[Bostonredsox]

Here's a fact that is relevant on so many levels, yet I'm gonna apply SAID FACT (based on my expansive physiology knowledge 🙂laugh🙂 to

one group:

ANXIETY-RIDDEN FIRST YEAR ANESTHESIA RESIDENTS that feel Under The Gun To Hurry Their Intubation Since Dude May Die From Hypoxemia If I Take Too Long.

(they won't....the moral of This Story is to teach you to Use Physiology To Your Benefit)

CASE IN POINT:

You've got your normal case as a CA-1: A laparoscopic gallbladder or a hysterectomy or a ureteral stone removal... OK OK OK you're prepared since you're not a SLACKER

Patient in the OR, monitors on, you RECHECK your setup and all is good so you proceed with your induction consisting of

1) 10 mg rocuronium defasciculating dose (make sure you give it followed quickly by induction so your patient doesn't experience that "weak" feeling)

2) Propofol 150mg (with a delta of 50mg depending on your interpretation of the patient's Dose Response Curve, which you can easily figure out (very important interpretation...someone please call me out on this topic later on a New Thread)

3) Succinylcholine

4) Now you are mask ventilating the patient

5) INTUBATION. SOMETHING YOU

HAVE TO BECOME A

ROKKSTARR AT IF YOU WANNA BE AN

ANESTHESIOLOGIST....

WUH OH

you're having problems with the intubation as a

NEW ANESTHESIA RESIDENT

which we've all had but you're in the moment and you're trying to Sweep The Tongue but it's not working so you TRY AGAIN with the same result but this time your technique is a little better at which point (probably 60 seconds later) you look at your Attending for help instead of trying again since you're CONVINCED you're about to

KILL THIS DUDE FROM HYPOXEMIA

No man.

Actually, if it's a healthy patient who's been preoxygenated,

GO AHEAD AND LEAVE TO TAKE A

QUICK WHIZZ THEN COME BACK

The O2 sat is still gonna be ok.

Dear Early Anesthesia Residents,

Think about the physiology contributing to the scenerio I posted, assuming you were putting to sleep a Healthy Young Person that you preoxygenated.

HOW MUCH TIME DO YOU THINK WILL ELAPSE BEFORE THE PATIENT DESATURATES?

In order to answer this question you need to recall some pulmonary function knowledge and recall how much oxygen is needed per minute to maintain bodily functions.

I'm gonna rephrase the question for simplicity purposes:

"I'm in the operating room and my patient is on the table, monitors on, everything is copasthetic. I place the oxygen mask (FiO2=1.0) on this healthy person's face with a good seal and the patient Breathes Deeply In And Out for a good

thirty seconds.

I induce and intubate but I forget to hook up the patient to the circuit.

"OH S H IT," I say to myself, "I'VE GOTTA TAKE A WHIZZ BEFORE THIS CASE."

(DISCLAIMER: This would NEVER HAPPEN. )

I leave the freshly preoxygenated, paralyzed, intubated patient that is NOT hooked up to the anesthesia machine circuit

to take a whiz.

HOW MUCH TIME DO I HAVE TO LEAVE

TAKE A WHIZ

AND RETURN

LIKE NOTHING HAPPENED?

(the answer will ASTOUND you)

this may seem like a dumb question to you all, but I am not an anesthesiologist. I am a future IM/CC. I only intubate people who are coding, or who will code eventually If I do not intubate them. That said, why 10mg of Roc then RSI with prop/succ? Is this just something you do in the controlled airway before an elective case to make induction smoother? I give prop/roc, prop/succ, etom/roc, etom/succ, etc etc for my floor/MICU RSIs, but I had never heard of giving a Non-depol to defasiculate then inducttion agent followed by depolarizer. And I use 1.2mg/kg of roc for mine, but it seems liek with 10mg you are just trying to get a little bit of effect with it before starting your true RSI with succ. What is the physiology and reasoning for that if you have some spare time. thanks.

 

[Dwindlin]

Defasiculating dose. Theoretically supposed to prevent/minimize defasiculations with succs.

Whether it works I believe is a topic for debate.


Sent from my iPhone using Tapatalk

 

[VentdependenT]

its bullhonkey and has NO role in emergent intubations

 

[Idiopathic]

this may seem like a dumb question to you all, but I am not an anesthesiologist. I am a future IM/CC. I only intubate people who are coding, or who will code eventually If I do not intubate them. That said, why 10mg of Roc then RSI with prop/succ? Is this just something you do in the controlled airway before an elective case to make induction smoother? I give prop/roc, prop/succ, etom/roc, etom/succ, etc etc for my floor/MICU RSIs, but I had never heard of giving a Non-depol to defasiculate then inducttion agent followed by depolarizer. And I use 1.2mg/kg of roc for mine, but it seems liek with 10mg you are just trying to get a little bit of effect with it before starting your true RSI with succ. What is the physiology and reasoning for that if you have some spare time. thanks.

it has been demonstrated to reduce fasciculations (not defasciculations) in patient when sux is given, although you probably need to give it >3 min prior to the sux dose. May be helpful in alleviating post-sux myalgias (not great data) and probably helps with sux-induced increases in ICP. Would not use this for true RSI, for a number of reasons. you will need to increase your dose of sux if you do this, likely, unless you are already using 1.5mg/kg (i use about 0.8-1.0)

i also use it as a priming dose, mainly since our vec and roc seem to have such a variable onset, but you probably need at least 3 minutes here as well, so I will do it as we roll in the room, before monitors are on (again, in the patient without significant cardiopulmonary comorbidity who does not look like a difficult airway).

 

[pgg]

Defasiculating dose. Theoretically supposed to prevent/minimize defasiculations with succs.

Whether it works I believe is a topic for debate.

Oh it works to minimize defasciculations - it's whether it's good for anything else that's debatable. 🙂

I haven't given a defasciculating dose of a nondepolarizer since the last time I was instructed to as a resident. I don't see the point. I also try hard to avoid succ and generally never use it except for RSIs, but that's just my bias.

 

[jwk]

I'm gonna rephrase the question for simplicity purposes:

"I'm in the operating room and my patient is on the table, monitors on, everything is copasthetic. I place the oxygen mask (FiO2=1.0) on this healthy person's face with a good seal and the patient Breathes Deeply In And Out for a good

thirty seconds.

I induce and intubate but I forget to hook up the patient to the circuit.
"OH S H IT," I say to myself, "I'VE GOTTA TAKE A WHIZZ BEFORE THIS CASE."

(DISCLAIMER: This would NEVER HAPPEN. )

I leave the freshly preoxygenated, paralyzed, intubated patient that is NOT hooked up to the anesthesia machine circuit

to take a whiz.

HOW MUCH TIME DO I HAVE TO LEAVE

TAKE A WHIZ

AND RETURN

LIKE NOTHING HAPPENED?

(the answer will ASTOUND you)

Although your point of course is well taken and is a truism, I feel compelled to yanketh thy chain (in large print and color, no less) and point out that in your re-stated scenario, your patient was not in fact pre-oxygenated, although they were of course de-atelectasized (I made that word up for you) which contributed to their overall outstanding oxygen saturation and adequate micturition time. 😀

 

[Dwindlin]

Oh it works to minimize defasciculations - it's whether it's good for anything else that's debatable. 🙂

This is what I meant, I posted that on my phone and realized shortly after that it was not exactly what I wanted to say but editing on the phone is a PITA.

 

[scudrunner]

Although your point of course is well taken and is a truism, I feel compelled to yanketh thy chain (in large print and color, no less) and point out that in your re-stated scenario, your patient was not in fact pre-oxygenated, although they were of course de-atelectasized (I made that word up for you) which contributed to their overall outstanding oxygen saturation and adequate micturition time. 😀

Sure they were. The circuit is just still attached to the mask, which is sitting next to the patient's head.

 

[jetproppilot]

this may seem like a dumb question to you all, but I am not an anesthesiologist. I am a future IM/CC. I only intubate people who are coding, or who will code eventually If I do not intubate them. That said, why 10mg of Roc then RSI with prop/succ? Is this just something you do in the controlled airway before an elective case to make induction smoother? I give prop/roc, prop/succ, etom/roc, etom/succ, etc etc for my floor/MICU RSIs, but I had never heard of giving a Non-depol to defasiculate then inducttion agent followed by depolarizer. And I use 1.2mg/kg of roc for mine, but it seems liek with 10mg you are just trying to get a little bit of effect with it before starting your true RSI with succ. What is the physiology and reasoning for that if you have some spare time. thanks.

Hey dude,

I LIKE SUCCINYLCHOLINE.

I use it on every induction I perform unless there is a screaming contraindication.

Succinylcholine causes muscle fasciculations that can cause myalgia pain for the patient postoperatively. To eliminate or at least ameliorate fasciculations, turns out if you give a little non-depolarizer before giving the sux, fasciculations can be largely prevented.

HERES THE PROBLEM:

Giving 5mg rocuronium as a de-fasic dose is unpredictable... more patients than what's acceptable to me people will get weak if you give it a few minutes before induction.

SO what I do is give 10mg right before I give the propofol, which seems to work fairly well in preventing fasiculations with succinylcholine utilization.

10mg of roc is a big dose for defasic so NEVER give it unless you are immediately following with propofol (or whatever.)

In your business of intubating the Trying To Die Population this is a non issue man.

As an aside, I'm gonna give you some friendly advice:

GET AWAY FROM USING ROCURONIUM (or any other non-depolarizer) ON EMERGENCY AIRWAYS

YOU'RE ASKING FOR TROUBLE, DUDE.

If you need to paralyze for an emergent intubation,

USE SUCCINYLCHOLINE.

I'm an anesthesiologist. I would

ALMOST NEVER

use a non-depolarizing muscle relaxant on a dude requiring emergent intubation.

 

[sevoflurane]

Given a favorable airway, try Prop AND Roc AND lido all at the same time in the same syringe. 50-100mcgs of fent after the consent is signed and you are on the way back.
I know that is not what is taught, but it's never failed me and worth knowing about if you wanna be well rounded and a fast ninja.

If you are using sux, then wait a bit longer for that one.

 

[Substance]

I am no anesthesiologist, but I like doing these quizzes.

If you pump the dude full of oxygen, and his lungs are theoretically 100% oxygen in the alveoli, and the functional residual capacity of an adult male is about 2400ml or so, and the resting VO2 for an adult male is approximately 10x less than normal VO2 max(which for a healthy adult man is about 30ml/kg/min), then since he's approximately 100kg, that would make it 3x100=300ml/min. Dividing 2400ml of O2 in the FRC by 300ml/min VO2 at rest gives you about eight minutes.

Am I correct?

 

[jetproppilot]

Although your point of course is well taken and is a truism, I feel compelled to yanketh thy chain (in large print and color, no less) and point out that in your re-stated scenario, your patient was not in fact pre-oxygenated, although they were of course de-atelectasized (I made that word up for you) which contributed to their overall outstanding oxygen saturation and adequate micturition time. 😀

Love it man.

See Scudrunner's reply tho.

Nice try homie. 😀

 

[jetproppilot]

I am no anesthesiologist, but I like doing these quizzes.

If you pump the dude full of oxygen, and his lungs are theoretically 100% oxygen in the alveoli, and the functional residual capacity of an adult male is about 2400ml or so, and the resting VO2 for an adult male is approximately 10x less than normal VO2 max(which for a healthy adult man is about 30ml/kg/min), then since he's approximately 100kg, that would make it 3x100=300ml/min. Dividing 2400ml of O2 in the FRC by 300ml/min VO2 at rest gives you about eight minutes.

Am I correct?

The point of this post was to give comfort to CA-1s during their learning curve days of intubation.

Substance and others have used their knowledge to accurately answer the question. Of course please remember there is wide variability within humans... we are not robots... I'd be comfortable telling you that you have

FIVE MINUTES.

During your first six months or so you're gonna feel RUSHED.

I think we've demonstrated in this post that you can, within reason,

TAKE YOUR TIME MAN

It's all good. 👍

Which means I'll

BE BACK IN PLENTY OF TIME AFTER MY WHIZ

Nice job, dudes.

 

[VentdependenT]

250ml/min o2 consumption. 200ml/min co2 production. hence the .8 in your alveolar gas equation.

FRC is roughly 2L. FRC is the amount of lung left inflated after tidal volume exhalation. It represents the balance of the chest wall compliance and lung elasticity. After induction some portion goes atelectatic resulting in loss of gas exchanging tissue. Assuming your pt doesnt have nasty lungs, you should get 8minutes, however it is less because of atelectasis from general anesthesia (from: guts pushing into chest, chest wall slacking off, etc).

In reality something like 6min.

If you leave a nasal canula blasting full bore in this healthy patient you can literally jack around with intubation for at least another several minutes. See the NO DESAT literature.

 

[jetproppilot]

250ml/min o2 consumption. 200ml/min co2 production. hence the .8 in your alveolar gas equation.

FRC is roughly 2L. FRC is the amount of lung left inflated after tidal volume exhalation. It represents the balance of the chest wall compliance and lung elasticity. After induction some portion goes atelectatic resulting in loss of gas exchanging tissue. Assuming your pt doesnt have nasty lungs, you should get 8minutes, however it is less because of atelectasis from general anesthesia (from: guts pushing into chest, chest wall slacking off, etc).

In reality something like 6min.

If you leave a nasal canula blasting full bore in this healthy patient you can literally jack around with intubation for at least another several minutes. See the NO DESAT literature.

👍👍

 

[loveoforganic2]

I've heard the 5 minutes to desat stat before by a resp therapist that handles some of our "preclinical clinical" education, but never tried out the math behind it - good to see! If they're sitting there for 5 minutes paralyzed with no effective CO2 expulsion, though, how much do you have to worry about hypercapnea as you "don't worry about the desat"?

 

[okayplayer]

I've heard the 5 minutes to desat stat before by a resp therapist that handles some of our "preclinical clinical" education, but never tried out the math behind it - good to see! If they're sitting there for 5 minutes paralyzed with no effective CO2 expulsion, though, how much do you have to worry about hypercapnea as you "don't worry about the desat"?

Assuming they don't have pulmonary hypertension or intracranial hypertension, that nominal increase in CO2 is not generally harmful and very easily corrected once you start ventilating them.

 

[Bostonredsox]

Hey dude,

I LIKE SUCCINYLCHOLINE.

I use it on every induction I perform unless there is a screaming contraindication.

Succinylcholine causes muscle fasciculations that can cause myalgia pain for the patient postoperatively. To eliminate or at least ameliorate fasciculations, turns out if you give a little non-depolarizer before giving the sux, fasciculations can be largely prevented.

HERES THE PROBLEM:

Giving 5mg rocuronium as a de-fasic dose is unpredictable... more patients than what's acceptable to me people will get weak if you give it a few minutes before induction.

SO what I do is give 10mg right before I give the propofol, which seems to work fairly well in preventing fasiculations with succinylcholine utilization.

10mg of roc is a big dose for defasic so NEVER give it unless you are immediately following with propofol (or whatever.)

In your business of intubating the Trying To Die Population this is a non issue man.

As an aside, I'm gonna give you some friendly advice:

GET AWAY FROM USING ROCURONIUM (or any other non-depolarizer) ON EMERGENCY AIRWAYS

YOU'RE ASKING FOR TROUBLE, DUDE.

If you need to paralyze for an emergent intubation,

USE SUCCINYLCHOLINE.

I'm an anesthesiologist. I would

ALMOST NEVER

use a non-depolarizing muscle relaxant on a dude requiring emergent intubation.

Me either man. But the emergent airway with a K of 6.4 or known elevated ICP, head trauma, i use etomidate and double dose ROC.

 

[ssmallz]

If you leave a nasal canula blasting full bore in this healthy patient you can literally jack around with intubation for at least another several minutes. See the NO DESAT literature.

Assuming the pt is apneic this part of the post is not true and a good learning point for CA1s as to why

 

[scudrunner]

Assuming the pt is apneic this part of the post is not true and a good learning point for CA1s as to why

Seems like the O2 would blast in the nose then promptly exit through the mouth.

 

[VentdependenT]

Assuming the pt is apneic this part of the post is not true and a good learning point for CA1s as to why

No such thing as apneic oxygenation?

 

[VentdependenT]

Seems like the O2 would blast in the nose then promptly exit through the mouth.

Would it?

 

[scudrunner]

Would it?

Just my thought if the pt is apneic and the epiglottis is hanging down and partially blocking the cords. I suppose if you stir up the air enough you could get some gas exchange, but there is a huge column of dead space to diffuse past before you get to any alveoli.

 

[pgg]

Assuming the pt is apneic this part of the post is not true and a good learning point for CA1s as to why

What do you mean? Assuming* the airway isn't obstructed, I would expect apneic oxygenation to buy you some extra time.




* perhaps a big assumption

 

[anes]

Just my thought if the pt is apneic and the epiglottis is hanging down and partially blocking the cords. I suppose if you stir up the air enough you could get some gas exchange, but there is a huge column of dead space to diffuse past before you get to any alveoli.

To reiterate.... No such thing as APNEIC oxygenation?

 

[pgg]

Just my thought if the pt is apneic and the epiglottis is hanging down and partially blocking the cords. I suppose if you stir up the air enough you could get some gas exchange, but there is a huge column of dead space to diffuse past before you get to any alveoli.

Apneic oxygenation isn't dependent upon diffusion. Absorption of O2 in the alveoli reduces volume and you get actual mass flow of fresh O2 into the lungs. Assuming no obstruction of course.

 

[fakin' the funk]

Don't forget, 3ml O2/kg/min is "baseline" or anesthetized O2 consumption (VO2).

Once you start doing repeated laryngoscopy and get some serious sympathetic stimulation, that VO2 gets jacked.

Like, Usain Bolt 100-meter world record jacked. You see this as increased HR and BP.

Don't count on 8 minutes.

 

[rsgillmd]

Don't forget, 3ml O2/kg/min is "baseline" or anesthetized O2 consumption (VO2).

Once you start doing repeated laryngoscopy and get some serious sympathetic stimulation, that VO2 gets jacked.

Like, Usain Bolt 100-meter world record jacked. You see this as increased HR and BP.

Don't count on 8 minutes.

I don't think they are counting on 8 minutes -- more like 5-6 minutes as Jet said.

My vice chair during residency told me that he once made a resident wait after induction until SpO2 started to decrease before doing laryngoscopy. It was purely an academic exercise in an easy airway/easy to ventilate patient. I think he said it was about 4-5 minutes wait. This was a few years ago, so I am going purely on recall. But it fits with the math, allowing for a decrease in FRC from supine position and induction of GA.

 

[Sonny Crocket]

Don't forget, 3ml O2/kg/min is "baseline" or anesthetized O2 consumption (VO2).

Once you start doing repeated laryngoscopy and get some serious sympathetic stimulation, that VO2 gets jacked.

Like, Usain Bolt 100-meter world record jacked. You see this as increased HR and BP.

Don't count on 8 minutes.

There isn't going to be any sympathetic stimulation because I will give the customary 100mcqs of fentanyl at least two min before I intubate which will totally obliterate the response to laryngoscopy!!!