Timing of ketamine vs. rocuronium

TXmed

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Jusst saw this today. Interesting point being made. The biggest thing i took from it was that maybe we should be dosing roc closer to 2mg/kg.
 

MonkeyArrow

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Reading through the post and all the (quite brilliant, actually) comments, this just reemphasizes the need, at least IMHO, to practice medicine and evaluate everything on a case-by-case basis. Furthermore, this post really reinforces the concept of worrying about the details and really being focused on not just passing the tube through the cords, but everything leading up to and after the actual intubation.

Is pushing Roc followed by Ketamine applicable in every situation? No, someone who you may be incubating for airway protection or failure to manage secretions hopefully is not in fulminant respiratory failure yet, and therefore, does not have the time critical nature as intubating a CTD septic patient. I understand that the argument being made is that the goal of Roc-Ketamine is to decrease lag time between patient autonomous breathing and having conditions conducive to passing the tube. However, although BiPAP was mentioned as a backup, there is no reason why you can't continue to bag or otherwise ventilate your patient in-between induction and intubation, especially if you give a sedative first. Also, Roc-Ketamine is not the only induction sequence. Sux has a somewhat shorter onset time, etomidate can be used as an induction agent, and so on.

You must really take a step back and evaluate your patient and your plan each time you think about intubating.
 
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Carlos Danger

Carlos Danger

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The problem with trying to precisely time the onset of these drugs is that pharmacokinetics vary from individual to individual, which means that so does the onset of these drugs. There is no way to predict with any precision how fast these drugs will take affect in any given patient. I think there are simpler, more proven ways to speed the onset of your paralytic, or to shorten the time between apnea and paralysis.
  • Why not use a priming dose of your paralytic? They work, and are easy to do.
  • Why not use a smaller dose of ketamine so that the patient maintains spontaneous breathing while the paralytic takes effect? Isn't that why we switched from etomidate to ketamine in the first place?
  • Why not use magnesium or remifentanil or ephedrine or high-dose lidocaine to speed the onset of your paralytic, and to reduce the induction agent dose?
  • If you are really worried about the onset of your paralytic, why not just use sux? As I've said 100x before, the bad rap that sux has gotten in the FOAMed community in recent years is completely unfounded. If you really want someone's cords to relax quickly, sux is where it's at.
 
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StCEMT

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You actually asked my two questions @Remi (#2 and 4 on your response). I cant RSI, so what knowledge I have of it is strictly stuff that I have learned here. However, it seems barring any sux contraindications that it would be a perfectly reasonable solution to cut those times down.

From what I understand, Ketamine has a longer onset time than Sux, so in this case I assume the order they would be given would be reversed?

I am going to look up your mag reference, I don't recall hearing that mag could do that.
 

E tank

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I really couldn't disagree more with the rapid pre-whack of rocuronium. You blow the IV after that and prohibit any hypnotic from going in and you have a disaster. As uncommon as it is, I'd much rather blow an IV after hypnotic.

Also, getting caught up in a few tenths of a mg difference in dosing of rocuronium when the patient will be irretrievably paralyzed in the end is missing the point, I think. If succs like speed is what you're after with roc, give 3/kg of roc. You'll get very good relaxation almost immediately and you don't have to push it before your hypnotic.

Or, just use succs for pete's sake....
 

E tank

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From what I understand, Ketamine has a longer onset time than Sux, so in this case I assume the order they would be given would be reversed?

Enough ketamine would be working for significant disassociation to be occurring even if there were any meaningful consciousness. Not to put too fine a point on my bias, giving muscle relaxant before hypnotic (at least with just one IV) is for very uncommon circumstances and folks very familiar with doing it. IMHO, it is a very bad idea in the context of this conversation.
 

MonkeyArrow

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@Remi - could you please elaborate about the Sux bad rep? Also, what is FOAMed?
Not Remi but succs has gotten a bad reputation in the FOAMed world due to its relative contraindications. You theoretically should not use succs if the patient has hyperkalemia, has had a history of malignant hyperthermia, some say burn patients, those with denervation syndromes due to the potential for fasciculations, or a few other things. However, on the patient that your are RSIing, you don't often have lab values or the time to gather a full H&P, and thus, could be administering this drug to a patient while it is relatively contraindicated.

On the other hand, succinylcholine has been proven to have a faster onset and shorter duration, which are desirable traits in the RSI world. This debate of sux vs roc rages on.

Also FOAMed stands for Free Open Access Medical education, and refers to the increasing propensity to collaborate and share resources in the emergency medicine and critical care fields, such as making publications open access and having free blogs and podcasts, etc.
 

VentMonkey

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And it's one of many "one is better than the other" arguments we tend to, at times,(needlessly) pine over.

Honestly---in the prehospital setting---more often than not, Succs seems more than efficient. If all you carry is Roc chances are you'll have covered your bases for the above mentioned select patient population as @MonkeyArrow has articulated.

I'm not saying that these patients are not out there, and that this cannot happen when the wrong patient is given Succs, I'm just saying that most patients you will see that require these induction agents do, and have done just fine with Succs; the same can be said for Etomidate even though Ketamine has been found to be sexier for multiple reasons; though, this drug also has its beneficial patient demographic.

All that said, without these arguments we would be stuck in the proverbial "mud" like many providers tend to be after too many years on the job. We all know these types, and how dangerous they're are, so there's also that to consider.
 

E tank

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I'm not saying that these patients are not out there, and that this cannot happen when the wrong patient is given Succs, I'm just saying that most patients you will see that require these induction agents do, and have done just fine with Succs; the same can be said for Etomidate even though Ketamine has been found to be sexier for multiple reasons; though, this drug also has its beneficial patient demographic.

Amen brother...preach it...succs and etomidate...ambrosia...screw them all...
 

VFlutter

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I totally agree with timing RSI meds based off onset of action as opposed to the blanket statement of "Sedation before paralysis". I wish I had the option of a higher dosage of Roc however I still have a 1.2mg/kg max.

As far as blowing the IV with the paralytic bolus just make sure you have two forms of access. Two is one and one is none.
 

StCEMT

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So I understand there are times were Roc > Sux based on what I have read. That being said, barring those reasons, does how quickly you want your onset to be play a role in what you decide to use and if so what are the things that factor into that decision? Say the Etomidate/Sux rapid onset vs. Roc/Ketamine slower onset....and I suppose duration for both of those as well. Or is it more a matter of personal preference and comfort?
 

CWATT

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So I understand there are times were Roc > Sux based on what I have read. That being said, barring those reasons, does how quickly you want your onset to be play a role in what you decide to use and if so what are the things that factor into that decision? Say the Etomidate/Sux rapid onset vs. Roc/Ketamine slower onset....and I suppose duration for both of those as well. Or is it more a matter of personal preference and comfort?

My knee-jerk reaction is that if we feel the need to accept control of the airway, it's in the patient's best interest to do so sooner than later. I believe most practitioners use the approach to first look for reasons NOT to ET someone, but if it's indicted and a less-invasive airway management intervention or reverseable cause is not present, then time would presumably be of the essence. I would therefore believe a short onset of action would be most desirable.
 

VentMonkey

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but if it's indicated and a less-invasive airway management intervention or reverseable cause is not present, then time would presumably be of the essence. I would therefore believe a short onset of action would be most desirable.
Yes, and no. While rapid is certainly the first word in the induction sequence, it is a somewhat relatively subjective term.

Are we going to sit and fiddle around? No, but as you presented in your YouTube post of the EM doctor running through a fairly standard RSI (good review, and tutorial for those unfamiliar with advanced airway management, BTW) there was no rush.

More often than not, the sequence of med-push events is rapid, but on the whole a prepared approach, as he eludes to, should take up most of your time.

The entire procedure should not be rushed to the point that the basic fundamentals are overlooked; this will create a longer delay, and increase chances of both hypoxia, and aspiration, in turn defeating the purpose of the induction.

As they say:
Failing to prepare is preparing to fail.

This statement alone should sum up and guide a quick, and efficiently performed successful RSI.
 

StCEMT

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True, but depending on the reason I wanted to intubate would also factor into how quickly I wanted it to happen. A decompensating cardiogenic shock patient I am going to take a little more time to make sure they are hemodynamically stable before intubating. Where as a airway burn I will be a bit more streamlined and trying to reach the same point faster. @VentMonkey put my thoughts into words a little more eloquently.
 
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Carlos Danger

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It is true that a large dose of roc approaches the onset time of sux. Close enough that the difference is considered statistically insignificant, which is why people get away with saying there is "no difference" in onset time between the two. Still, most studies show a difference of anywhere from about 7-14 seconds or so from injection to acceptable intubating conditions. Statistically significant or not, if no one felt that 7-14 seconds wasn't clinically significant in at least some cases, this article would have never been written.

If you want to shorten the interval between administration of your first drug and appearance of good intubating conditions, there are a bunch of ways to skin that cat. But of all of them, I think using a technique that relies heavily on what the textbooks tell us about onset times in normal physiology is the diciest. It'll probably work fine most of the time, but there is plenty of room for problems.

The lengths that we'll go to to avoid using sux where it is clearly indicated is beginning to become comical. I don't think it's any coincidence that the people who advocate these techniques tend to be people who don't even intubate all that much.
 
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