Who still uses nitrous?

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Noyac

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Do you use it in peds only?

Are you worried about MI's ( not in peds of course)?

Do you use it in traumas?

Worried about DVT's?

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All the time for my outpatient cases, since they took away desflurane (too expensive).
 
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C/s post baby, peds. otherwise, virtually never

FFP you need to show a low flow cost per hour, and look at pacu stay/cost. Of course the pharmacy budget silo doesn't care about that though.
 
it has it's uses although they are fairly limited. I use it a little in peds, emergency c-sections under GA, and in old half dead patients that can't seem to tolerate volatile anesthetic gases.
 
Unless there is a contraindication, I use it fairly often in the last 10 minutes to speed emergence/when the closure will take an unpredictable amount of time (which is pretty often because I am in academics - for the next three weeks anyway). Never really for longer than that.
 
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Same for me as okayplayer. But I'm not in academics. Mostly when waking up backs.
 
Unless there is a contraindication, I use it fairly often in the last 10 minutes to speed emergence/when the closure will take an unpredictable amount of time (which is pretty often because I am in academics - for the next three weeks anyway). Never really for longer than that.

I get the patient breathing spontaneously on sevo/iso well before the procedure is over, titrate in narcotics, and then extubate deep as the surgeon applies the dressing. This gives me a fast turnover without using all that nasty nitrous.

I use nitrous only for:
1. peds mask inductions
2. if i need a supplement during a c-section
3. for difficult IVs, i sometimes bring the patient to the OR and put them on a little bit of gas.
 
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Nitrous? What's that?

Only for masking down peds cases, then it goes off.
 
Nitrous:

Peds
Mask Inductions
C-sections (sometimes)
Wake-Ups (last 20-30 minutes of case) as its speeds up emergence due to the second gas effect

I'd rather NOT use it in the elderly or ASA4 patient as that is the population nitrous oxide may do the most harm. Instead, I place a BIS and run the Sevo at 0.4-0.5 MAC which is usually enough to keep the BIS below 60.
 
There's data somewhere that in experienced hands (ie in practice), nitrous doesn't speed emergence when compared to sevo alone.
 
It is used just about all the time at my place, people seem to love it. It seems to get used in TIVA cases as well, which is silly IMHO.
 
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Nitrous:

Peds
Mask Inductions
C-sections (sometimes)
Wake-Ups (last 20-30 minutes of case) as its speeds up emergence due to the second gas effect

I'd rather NOT use it in the elderly or ASA4 patient as that is the population nitrous oxide may do the most harm. Instead, I place a BIS and run the Sevo at 0.4-0.5 MAC which is usually enough to keep the BIS below 60.
Why?
 
Nitrous impairs DNA synthesis. You better make sure the baby is out before you turn that stuff on.

(Man, I'd make a great plaintiffs attorney... I smell a new career if this anesthesia stuff doesn't pan out. Not too late for law school.)
 
Nitrous impairs DNA synthesis. You better make sure the baby is out before you turn that stuff on.

(Man, I'd make a great plaintiffs attorney... I smell a new career if this anesthesia stuff doesn't pan out. Not too late for law school.)


So 6-8 minutes of Nitrous oxide to the mommy then maybe a bit to baby causes DNA issues? Really? We are talking trace amounts with exposure time of under 8 minutes.
 
Until the results of the Enigma 2 Study are released later this year I am cautious as to the use of N20.

http://www.enigma2.org.au/


http://www.enigma2.org.au/centres

The trial has been completed with 7,100 patients participating in the study. Now, we await the results which will clarify the issue.

will make for interesting reading -- but looks like nitrous will be back in vogue

results presented at anzca asm
http://www.anzca.edu.au/events/ANZC...sor-paul-myles-principal-researcher-enigma-ii

and media release
http://www.anzca.edu.au/communications/Media/pdfs/ENIGMA2_6May_2014 pdf.pdf
 
We do mask inductions with parents in room, so 3 min of nitrous before the sevo makes for a smooth mask down in peds.

And i use it for emergence on longer cases and when i iso...i know there are ppl out there that can get 10 min discharges with iso...i have never honed that skill :)

My attendings would usually rec it for those hypotensive patients...but i always felt way more comfortable just starting a pressor drip.
 
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Thank You. Nitrous oxide is now back on the table (literally) for me in all areas except outpatient where I will restrict its use due to possible increase in N/V.
 
Nitrous impairs DNA synthesis. You better make sure the baby is out before you turn that stuff on.

(Man, I'd make a great plaintiffs attorney... I smell a new career if this anesthesia stuff doesn't pan out. Not too late for law school.)

N2O can be a teratogen, but only in extremely young embryos. It slowly depletes the organism of B12... Mice start to slow long-term effects after a few hours of exposure. Something the size of a newborn human could show effects (theoretically) after a week or so.

In other words... N2O is a non-toxic drug.



But as for use, the only one I see is light sedation (ie. dentists office...)
 
So 6-8 minutes of Nitrous oxide to the mommy then maybe a bit to baby causes DNA issues? Really? We are talking trace amounts with exposure time of under 8 minutes.

If you're a lawyer. And a hand-picked jury.
 
"Although our study did not measure children having surgery, or women using nitrous oxide in the labour ward as pain relief, we can be confident that it is also safe to use in those areas."

:rolleyes:
 
Thank You. Nitrous oxide is now back on the table (literally) for me in all areas except outpatient where I will restrict its use due to possible increase in N/V.
I work in an ASC, and the N/V rate for under 2 hour-cases on 50% nitrous+sevo is about 1-2% (usually the kind of people who get nauseous from any inhalational anesthetic). Of course, all patients get decadron and zofran automatically.

Regarding toxicity: every drug can be toxic for the right patient. You can induce an AKI in the right patient just by using aspirin. Same level of concern for nitrous and severe pulmonary hypertension.
 
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Nitrous impairs DNA synthesis. You better make sure the baby is out before you turn that stuff on.

(Man, I'd make a great plaintiffs attorney... I smell a new career if this anesthesia stuff doesn't pan out. Not too late for law school.)
This is a joke, right?
 
http://www.ncbi.nlm.nih.gov/pubmed/11049886

http://www.ncbi.nlm.nih.gov/pubmed/18813045

As the Prof eluded to in the video above from Australia, there is a lot of talk about the dangers of Nitrous these days. Personally, I have only use it for pedi inductions for the last 10 yrs. but I always practiced at altitude and never really found it very effective otherwise. So what does increased homocysteine levels cause?
Cardiac morbidity
Venous thromboembolism

With all the attention to DVT's and PE's these last few years, is nitrous really worth it when used for more than a hour or so?

I don't claim to have the answers. I just raise the question.
 
I think it has it's uses, and it's limitations - like everything else.

I think the analgesia is useful in reducing opioid requirements intraoperatively for patients who won't have much post procedure pain -- shoulder relocations come to mind... in much the same way remi is useful, of course it's much less potent - but then it's cheap and convenient. The increased PONV in such situations then can be weighed against the increased PONV from increased intra-op opioid.

I use it to reduce volatile use in the atonic obstetric PPH situation, and for gas inductions in paediatrics mostly.

Not so sure about the reduction in chronic pain ascribed to it - seems like a long bow to me



Pain. 2011 Nov;152(11):2514-20. doi: 10.1016/j.pain.2011.07.015. Epub 2011 Sep 1.
Chronic postsurgical pain after nitrous oxide anesthesia.
Chan MT1, Wan AC, Gin T, Leslie K, Myles PS.
Author information

Abstract
Nitrous oxide is an antagonist at the N-methyl-D-aspartate receptor and may prevent the development of chronic postsurgical pain. We conducted a follow-up study in the Evaluation of Nitrous Oxide in the Gas Mixture for Anaesthesia (ENIGMA) trial patients to evaluate the preventive analgesic efficacy of nitrous oxide after major surgery. The ENIGMA trial was a randomized controlled trial of nitrous oxide-based or nitrous oxide-free general anesthesia in patients presenting for noncardiac surgery lasting more than 2 hours. Using a structured telephone interview, we contacted all ENIGMA trial patients recruited in Hong Kong (n=640). We recorded the severity of postsurgical pain of at least 3 months' duration that was not due to disease recurrence or a pre-existing pain syndrome, using the modified Brief Pain Inventory. The impact of postsurgical pain on quality of life was also measured. Pain intensity, opioid and other analgesic requirements during the first week of surgery, were retrieved from the trial case report form and medical records. A total of 46 (10.9%) patients reported pain that persisted from the index surgery, and 39 (9.2%) patients had severe pain. In addition, patients with chronic pain rated poorly in all attributes of the quality-of-life measures compared with those who were pain free. In a multivariate analysis, nitrous oxide decreased the risk of chronic postsurgical pain. In addition, severe pain in the first postoperative week, wound complication, and abdominal incision increased the risk of chronic pain. In conclusion, chronic postsurgical pain was common after major surgery in the ENIGMA trial. Intraoperative nitrous oxide administration was associated with a reduced risk of chronic postsurgical pain.

Copyright © 2011 International Association for the Study of Pain. All rights reserved.




Mostly ... I think enigma 2 will give us the evidence to allow it's judicious use.
 
I think the analgesia is useful in reducing opioid requirements intraoperatively for patients who won't have much post procedure pain -- shoulder relocations come to mind... in much the same way remi is useful, of course it's much less potent - but then it's cheap and convenient. The increased PONV in such situations then can be weighed against the increased PONV from increased intra-op opioid.

What do you mean by "opioid requirements"? What if you gave no opioid or nitrous and just gave some esmolol instead during this should reduction?

If your cerebral cortex is off, you aren't required to give pain medicine to treat hemodynamic changes. You can, and it's (usually) not wrong to, but you don't have to. Especially if PONV is a concern and you don't expect post-procedure pain.

Interesting paper you quoted. Wonder if other NMDA antagoists (i.e. ketamine, magnesium) would show the same effect. Suspect they would.

On topic, I use nitrous pretty much never. Occasionally to land a long anesthetic if I'm not sure between the attending, chief resident, or med student is closing. Very occasionally during the stimulating parts of a MAC if I don't want to give any opioid or ketamine for whatever reason. That's about it. Never ever for maintenance.
 
esmolol would probably work fine - i haven't tried it, but nitrous is easier

by opioid requirement - i mean how much opioid the patient requires to avoid excessive sympathetic response to noxious stimuli.

using opioid also reduces the chance of movement, biting on an lma, and generally being uncool.
of course - this could be achieved by more propofol, more volatile, or probably by esmolol - but as we all know a balanced approach with an opioid is generally better.

i'm just suggesting if something is very stimulating intra-op, but not so much afterward - short acting analgesia from nitrous and a reduced opioid dose probably makes sense.
 
Never. 8%sevo works just fine for peds inductions.
8% sevo works fine, but I think nitrous first is better. For a kid who's old enough to cooperate but young enough to still be terrified, a minute or so of just nitrous + oxygen before the stinky gas comes on can really smooth out the induction.

They go to sleep wide-eyed and goofy feeling, not freaked out from the guy wrestling and face-pinning them down with stinky gas.
 
8% sevo works fine, but I think nitrous first is better. For a kid who's old enough to cooperate but young enough to still be terrified, a minute or so of just nitrous + oxygen before the stinky gas comes on can really smooth out the induction.

They go to sleep wide-eyed and goofy feeling, not freaked out from the guy wrestling and face-pinning them down with stinky gas.

Probably true. I only ever do peds on yearly mission trips where we don't have nitrous....or sux. We do have a vaporizer that delivers 14% sevo and another that delivers 10% and people fight for those.
 
They go to sleep wide-eyed and goofy feeling, not freaked out from the guy wrestling and face-pinning them down with stinky gas.
There are studies (involving hypnosis) showing that the latter can be associated with PTSD later in life.
 
... I only ever do peds on yearly mission trips where we don't have nitrous....or sux.

why don't you take sux???
do you put in an iv before the gas induction each time?
what's your plan for laryngospasm?
 
why don't you take sux???
do you put in an iv before the gas induction each time?
what's your plan for laryngospasm?

I'm assuming on a mission trip your plan is to deal with it. 3rd world countries sometimes require non 1st world solutions for problems. A big dose of IV propofol and good positive pressure will break almost every laryngospasm.
 
Probably not with midaz.

Most of my own (unpleasant) early memories in life are associated with healthcare providers.
 
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I'm assuming on a mission trip your plan is to deal with it. 3rd world countries sometimes require non 1st world solutions for problems. A big dose of IV propofol and good positive pressure will break almost every laryngospasm.

i've never worked in the 3rd world - but would like to one day ... I'd have thought sux would be a drug I'd take with me though!
sure propofol works fine for laryngospasm
-- but sux can be given IM if laryngospasm happens before you get IV access - eg during gas induction
or if the IV gets dislodged or whatever in PACU and then the kid spasms.
and what if you need to do a RSI while on the mission?

PS nimbus - props to you for volunteering your time. i'm just asking what gives with the sux?
 
Nitrous impairs DNA synthesis. You better make sure the baby is out before you turn that stuff on.

(Man, I'd make a great plaintiffs attorney... I smell a new career if this anesthesia stuff doesn't pan out. Not too late for law school.)

The MoA of how N2O produces this ADR is inhibition of methionine synthase, right? It's not via the destruction of present folate or B12...

I don't think a brief exposure would be clinically significant, but I, of course, defer to an actual anes POV on this.
 
I use Nitrous frequently. The data questioning it's safety was always poor. Even nausea/vomiting is not well shown to be more frequent than sevo alone. All my partners use it regularly. In residency at a major program it was used regularly, so I guess some of my bias is institutional.

It's interesting how some techniques or drugs get such an unfair bad rap. Nitrous is awesome.
 
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