norcuron whats your thoughts

[Just Plain Ruff]

Maybe Cost is a factor? You know sometimes cost overshadows patient care at some services. Follow the money!!!!!!!!!!!!!!!!!!

[Doczilla]

Vecuronium (Norcuron) usually takes about 3-5 min to work, so that's why you won't see it as an initial paralytic. The point of RSI is to sedate and relax the patient and intubate them before the hypoxia sets in from ventilating them without a secure airway. Succinylcholine and rocuronium are both good agents for that.

Rocuronium lists for $50 a vial and has to be refrigerated, or changed out every month if stored at room temp. Succinylcholine is 90% effective at 90 days at room temp. That's room temp, not the temperature abuse that is common in ambulances.

We carry succinylcholine, changing out the vials every 3 months, as our initial paralytic. We carry vecuronium to keep the patient paralyzed once intubation has been achieved. Keep the patient sedated and still for the ride to the hospital and keep them from coughing or pulling out the tube or fighting it so hard they get a pneumo. Vec is cheap, and is packaged as a lyophilized powder that is shelf stable.

'zilla

[croaker260]

Vecuronium is a competitive agent in that it must compete with acetylcholine at the receptor site. This means that it's onset can take minutes at standard doses.

When used as a paralytic agent for the RSI procedure, I can see a few pitfalls:

1) Intubating conditions will take longer to develop

2) The duration is longer than the duration of many commonly used induction agents

3) There is no chance of a salvage after a few minutes if a failed airway situation develops

Personally, I'd say it's a suboptimal agent for facilitating RSI. I've used other competitive agents such as rocuronium but at relatively large doses to produce a relatively rapid onset. I also worked at a facility where vecuronium was used with varying degrees of success.

We are a ground 911 service. We carry vec and have for about 8 years or so and have done some form of RSI/MAI for about 15-20 years. We do not use it for induction at all, it is only used for maintenance of paralysis in conjunction with opioids and benzo's (typically Versed and/or Fentanyl) . We currently use combination of Ketamine, succs, opiods and benzo's for induction.

Vecs biggest downfall is its longer duration , Therefore it is only given after the tube is secured, ETCO2 and other monitoring are in place, and a c-collar in place. It has a longer effect than succs, typically 30-45 minutes. For that reason, we often use it side by side with Versed and Fentanyl which have similar clinical durations as well. In otherwords, when I administer vec, I strongly consider readministering Versed and/or Fentanyl as well. Of course general patient situation, hemodynamics, and clinical judgement all play a role.

[Just Plain Ruff]

Croaker260 said "and clinical judgement all play a role."

Say it isn't so?

[runswithneedles]

I kind of figured. Ive never used vecuronium before. Ive always used sux and roc but this in the OR with a anesthesiologist breathing down my neck in case i missed.

[Spock]

The only paralytic worse than vecuronium as an initial paralytic might be pancuronium but it would be close. Large doses of rocuronium (>1mg/kg) will come close to suxs for achieving intubating conditions but close only counts in horse shoes, hand grenades, and atom bombs. Push enough suxs (>2mg/kg) and you'll have intubating conditions in about 20 seconds. Always remember to administer an induction agent (etomidate or propofol are best) before the paralytic but in dire circumstances requiring RSI, I'd say push the induction agent with the suxs.

There are contraindications for suxs but in the face of losing an airway they become relative rather than absolute. Any RSI protocol MUST have at least two if not three alternative airway methods. King, LMA, Bougie, BVM, or some type of trach are possibilities although I am very partial to the King.

RSI requires strong medical control and close quality assurance measures to ensure success. If you will only use the protocol once or twice a year you should forget about it. There is a significant amount of literature that has been published on the subject and I'd strongly recommend that any protocol utilize an evidence based medicine approach. RSI should never be instituted in a casual manner. You can kill people if you don't do it correctly.

Edited July 29, 2013 by Spock

[theresqshop]

Vec is a reasonable RSI option in specific circumstances of which you will likely never encounter prehospital. SUX has been the standard for decades now but you will likely see it fall to the side over the next three to five years. ROC is simply a 'purified' or improved version of VEC. ROC in dosing of 1-1.2mg/kg will give you similar onset of intubating conditions as SUX. Unfortunately at this dosage it's duration will exceed 40 minutes and likely approach 90 minutes in some patients. VEC at 0.1mg/kg will give you intubation conditions in approximately 2-3 minutes in most patients. Keeping in mind that our job is to obtain a secure/patent airway without/prior to the patient vomiting (THE ONLY REASON WE DO RSI), we need to select a medication that gives us rapid onset while only compromising their muscular tone for a minimal period of time. To date, that drug has never existed. Now I said you'll see SUX go away over the next few years. Here's why..... SUX has some pretty significant side effects, a couple of which would likely prove fatal if encountered in the prehospital setting. These are few and far between, but serious none the less. ROC can give us the rapid onset we need at high doses, it's only limitation is the duration. In the next 60 days you'll see the FDA release a new drug called Suggamadex for sale from Merck Pharmaceuticals. Suggamadex was initially being designed as a 'packaging technology' for ROC. It's a cyclodextrin molecule, imagine a styrofoam cup with no bottom. It's molecular shape is such that it binds around a ROC molecule quite nicely. It's bonding is ionic but it's such a great fit the bond acts covalent (doesn't want to break... ever). When a drug of any kind is 'bound' like this, be it to another chemical you injected, or simply a protein in the blood, the drug is rendered unusable at it's target sites. It's bioavailability is reduced or eliminated. The idea was that by placing the ROC in this cyclodextrin molecule, they could shelf it without refrigeration for longer periods of time. One problem. It wouldn't release the ROC once injected. So, they decided to try injecting just the cyclodextrin into a patient that already had ROC on board. Result.... it grabbed all the ROC causing a reversal of effects. This reversal agent has demonstrated that regardless of the 'depth of muscular relaxation' induced by the ROC, they can be reversed almost immediately with minimal side effects using Suggamadex.

Long story short (too late I know), Suggamadex should allow us to use ROC for RSI and then safely reverse the paralytic should we fail the airway and need to get them breathing again. If this all plays out without any new surprises after release (remember Rapacuronium?), we will see SUX fade off into the sunset over the next few years.

Interesting note, Suggamadex will reverse VEC almost as well as it does ROC. In my practice I find VEC is actually more forgiving than ROC. If I need a drug to wear off or be reversible quickly, VEC is actually a little more reliable than ROC for that.

Best of luck with your protocol. Be sure to ask lots of questions, ask them to bring in someone that actually does this often to do your training (anesthesia).

Thanks

Will Wingfield

[Spock]

Will has interesting information that may be useful in the future but cost will always come into play and I agree that vec is more reliable than roc but both take a long time to wear off which makes them suboptimal for RSI. Nothing is cheaper than Suxs (pennies versus dollars) but if it had to go through FDA trials now it would never pass. I do remember rapacuronium and there were a lot of deaths before it was pulled.

Bottom line is any non-depolarizing neuromuscular blocking agent is a bad choice for RSi. The side effect profile of suxs is large but the profile doesn't apply to most prehospital situations. Crush injuries or ESRD (high K levels) may be the only ones I can think of just off the top of my head.

[croaker260]

First of all, really good discussion. Bravo.

Second, the contrindications/major concerns for suxs in our setting are:

1- Mysthenia gravis..While i have never personally seen this played out, my understanding is that it significantly prolongs Sux's duration making it comparable to other long acting paralytics. Since we do see these MG patients in the field, in this case I would do a more MAI than a true crash RSI..in otherwords heavy on the ketamine and benzo's/opioids and avoid succs.

2- Hyper-K+ is a real concern in the prehospital setting, but short of EKG changes we only have our detective skills to assist us to detect Hyper-K+ as most 911 agencies do not have readily available lab values. As I have seen a patient code in this very scenario.... here is my advice:

Disclaimer: THE FOLLOWING IS SIMPLY A STREET MEDIC TIP HARD WON OVER THE PAST 20 PLUS YEARS AND IS ANECTDOTAL...

As a general rule, if I find a patient in severe distress who would warrent RSI/MAI and they have a history of poorly controlled DM (with or without diagnosed renal failure) , or renal failure from any cause... then I avoid sux and use other pharmacological alternatives. I can think of at least 5-6 cases in the past 5 years where this has likely prevented adverse complications from giving sux in a hyperK situation (i.e. cardiac arrest). Not a lot, and certainly this is just anectdotal...but there it is. Your personal milage may vary.

Bottom line is any non-depolarizing neuromuscular blocking agent is a bad choice for RSi. The side effect profile of suxs is large but the profile doesn't apply to most prehospital situations. Crush injuries or ESRD (high K levels) may be the only ones I can think of just off the top of my head.

I think its important to differentiate the diference between the induction phase of RSI/MAI in airway management, and the maintanence /post induction phase here, as vec (combined with other agents) is a reasonable choice in the post induction phase for many services. But ypou and I are in total agreement that it is a veyr poor choice for the induction phase.

Edited August 2, 2013 by croaker260