How much Fentanyl

[Eli]

In 2003 I first encountered Fentanyl at a part time job. We had a standing order for 2-3 mcg/kg x 1. Further analgesic use required contact with MC. I had great success with that. A patient with his hand smashed between two trash trucks was in AGONY one minute and showed no distress after 200 mcg or so of Fentanyl. [It's been a long time and I don't remember the exact calculations]. Exactly 12 minutes later the Fentanyl wore off and he was in agony again. The inital dose was repeated with the same relief. 11 minutes later we were at the ED and of course they were not ready with any meds for the poor fella. I went around the nurses got the doc to stop what he was doing long enough to order more Fentanyl. I used it many times after that, though nothing quite as dramatic. I found the amount of relief and duration was pretty consistent at 2-3 mcg/kg. I had good results with Fentanyl to start and Morphine after that. I liked switching to Morphine because it lasted longer, though it wasn't *as* effective as the Fentanyl was at 2-3 mcg/kg. I did see horrible results with Fentanyl in the ED when they limited the dose to 50, 75, & 100 mcg. It was almost like giving nothing.

Currently the area I work in calls for 2 mcg/kg up to 100 mcg. I've never seen Fentanyl given above 100 mcg since. Even that service uses a loser dose today, though it isn't because of any bad results with the higher dose. It was simply a change in medical directors.

I'm curious what are the dosages are that everyone else is working with?

 

[NomadicMedic]

We use a broad 50 to 100 µg, up to 200 µg for adults. For pediatrics we use 2 µg per kilogram up to 100.

In my anecdotal experience I've found Fentanyl works exceptionally well for musculoskeletal pain, while morphine seem to perform better for visceral pain. However, that may have just been situational.

And frankly, it's moot as all I have for analgesia at my current service is Fentanyl.

 

[KellyBracket]

Opiod equivalence is a tricky topic, as is pain control in general.

Many opiod-equivalance tables list 10 mg of morphine as about the same as 100-200 µg of fentanyl. If the initial dose of morphine ought to be 0.1 mg/kg for severe pain, then fentanyl ought to be dosed at 1-2 µg/kg.

Except that we know that even that high a dose of morphine is not sufficient in many people (citation available, but quick response today!) So, it might not be too surprising that 2-3 µg/kg of fentanyl provides relief, while morphine "isn't strong enough."

All this talk of which opiod is strongest is silly - you give enough of any one of them, you get results. Nonetheless, people feel that if the "usual" dose of morphine doesn't work, then you need to switch to "the strong stuff." If you suggest giving morphine in doses significantly higher than this "usual dose," people get nervous about side effects. Which is odd, if you believe that it isn't strong enough...

Nevertheless, switching to a different opiod, one where we aren't sure of the "traditional" dose yet, may allow for more aggressive titration, since no one is sure of the "usual maximum." Researchers at Jacobi had more success with pain control when they stopped trying to push a higher mg/kg dosage of morphine, and simply switched to hydromorphone, despite the fact that the opioid-eqivalance was fairly similar.

Looking at recent evidence, feel free to read my post Prehospital Analgesia - Recent Research.

You can also note that fentanyl was dosed at about 1µg/kg for the initial dose, and 3 µg/kg for total EMS dose in the study entitled Fentanyl in the out-of-hospital setting: variables associated with hypotension and hypoxemia.

 

[NYMedic828]

Here in NYC our max fentanyl dose is 100mcg at 0.1mcg/kg. It is only in protocol for hypotensive pain management.

I laugh when people try and tell me we don't use fentanyl because it is "too strong." More often than not my coworkers don't understand equivalent doses. They think fentanyl is actually 100 times stronger than morphine when in reality it's 100 times more potent.

Wish I worked in a system that advocated pain management.

 

[Epi-do]

We used to be able to give an initial dose of up to 200 mcg of fentanyl, but it was changed in our last protocol update to a max initial dose of 150 mcg. We can give repeat doses of 50 mcg, up to a total max of 300 mcg before we have to call for orders. Fortunately, most of the docs around here are pretty good about giving additional orders if we need them.

 

[fast65]

In my system we don't have a "maximum dose" of any narcotic per say. Our fentanyl protocol calls for 50 mcg every 3 minutes until desired effect is obtained, or until respiratory depression occurs. There is no max dose on it. I typically find 100 mcg to work quite well on most people, it seems that 50 mcg is insufficient the majority of the time, but that's just been my experience.

For morphine we're allowed 2-5 mg every 3-5 minutes as needed. Once we reach 15 mg, we're required to give a copy of the report to our MD, however, we're still allowed additional dosing.

That being said, I've discovered what n7lxi said, to be true. I've had much better luck using fentanyl with extremity trauma than I have using morphine. Oddly enough though, I got lectured for giving 17 mg morphine and 200 mcg fentanyl over a 2.5 hour period, to a 25 yo F who crashed her ATV into a tree. Apparently I shouldn't have switched from morphine to fentanyl because "they work the same"...

 

[McGoo]

We give up to 25mcg per dose at five minute intervals, no maximum. The low loading dose means it can take a while to work, but it's usually quite effective. We don't use morphine.

If its traumatic pain, however, and fentanyl doesn't work, we can move to ketamine, either by itself or with fentanyl.

 

[Handsome Robb]

For us adults are .5-2 mcg/kg to a max single dose of 100 mcg and total dose of 300 mcg

Peds are the same but max total dose of 3 mcg/kg.

100 seems to be a good starting point but the other day I gave grandma 50 and it worked great.

 

[ShannahQuilts]

In terms of morphine not being strong enough, but being worried about the side effects, even 10mg of morphine has made me totally and utterly not care about breathing, while I was still in significant pain. Focusing on how much my kids need me while mechanically forcing myself to breathe, until the morphine wore off enough, was terrifying. I have refused opiates ever since.

I can't imagine what would have happened if I had taken enough morphine not to have significant pain anymore. Well, I guess I imagine I would have gone into respiratory arrest. The pain would've stopped eventually, but I doubt that would have been considered a win by my family.

 

[usalsfyre]

In terms of morphine not being strong enough, but being worried about the side effects, even 10mg of morphine has made me totally and utterly not care about breathing, while I was still in significant pain. Focusing on how much my kids need me while mechanically forcing myself to breathe, until the morphine wore off enough, was terrifying. I have refused opiates ever since.

I can't imagine what would have happened if I had taken enough morphine not to have significant pain anymore. Well, I guess I imagine I would have gone into respiratory arrest. The pain would've stopped eventually, but I doubt that would have been considered a win by my family.

I wasn't there, so I can't say so for sure, but if you were able to think through the situation, I doubt you were ever in true danger of apnea. The few people I've seen have true respiratory depression are approaching anesthetic levels of sedation. What it sounds like is an unpleasant anxiety related side effect.

The problem with stories like this is they discourage good pain management among lesser educated medics.

 

[ShannahQuilts]

I wasn't there, so I can't say so for sure, but if you were able to think through the situation, I doubt you were ever in true danger of apnea. The few people I've seen have true respiratory depression are approaching anesthetic levels of sedation. What it sounds like is an unpleasant anxiety related side effect.

The problem with stories like this is they discourage good pain management among lesser educated medics.

Looking at it from that standpoint, and knowing that the plural of anecdote is not data, maybe I should have said nothing. I do know, though, that watching my sats drop, while having no "urge" to breathe at all, was scary.

Well, and the other thing that was scary was having the nurses get upset.

But yeah, I guess I could accept that it was just an anxiety related side effect. I guess that begs the question, though: when I'm offered opiate pain killers, at what point is it sensible for me to say yes?

 

[NomadicMedic]

When you're monitored.

 

[NYMedic828]

Looking at it from that standpoint, and knowing that the plural of anecdote is not data, maybe I should have said nothing. I do know, though, that watching my sats drop, while having no "urge" to breathe at all, was scary.

Well, and the other thing that was scary was having the nurses get upset.

But yeah, I guess I could accept that it was just an anxiety related side effect. I guess that begs the question, though: when I'm offered opiate pain killers, at what point is it sensible for me to say yes?

You are in a hospital... If it was really that bad, which I find hard to believe, 0.2mg of narcan and you're fine...

It is so ridiculous to me that the one medication we can give, and carry an antidote for, people are afraid to give. (I am not advocating having the antidote as sole reason to give it)

 

[the_negro_puppy]

We have just been given Fentanyl to give intranasal to children. 1.5mcg/kg initial followed by second dose of 1.0mcg/kg total mack 100mcg Works ok.

Our intensive care paramedics have just received fentanyl for IV use.

Our pain protocols are pretty liberal- we can give unlimited morphine to adult patients in 2.5-5mg IV doses.

 

[the_negro_puppy]

Ill also add that our current ICP protocol for IV fent is:

initial dose 25-50mcg repeated at up to 50mcg every 5 mins no max dose.

They should be rolling IV fentanyl to us at some point

 

[Doczilla]

For pain that is so severe that im worried about maxing fentanyl, ill usually caulculate my doses, make a mental note, leave the fentanyl in the box, and use ketamine.

 

[Tigger]

Looking at it from that standpoint, and knowing that the plural of anecdote is not data, maybe I should have said nothing. I do know, though, that watching my sats drop, while having no "urge" to breathe at all, was scary.

Well, and the other thing that was scary was having the nurses get upset.

But yeah, I guess I could accept that it was just an anxiety related side effect. I guess that begs the question, though: when I'm offered opiate pain killers, at what point is it sensible for me to say yes?

When you are in more pain than non-opiate based pain medications can control. Do you usually notice an urge to breathe while you are doing your daily business?

 

[Doczilla]

I've juiced some dudes up pretty good with opiates. The lowest end of the respiratory scale ive seen is returning to normal respitations. When people are in severe pain, respiratory side effects rarely occur IF you titrate it. That's the whole deal, you need to titrate all of this stuff.

 

[usalsfyre]

Looking at it from that standpoint, and knowing that the plural of anecdote is not data, maybe I should have said nothing. I do know, though, that watching my sats drop, while having no "urge" to breathe at all, was scary.

Well, and the other thing that was scary was having the nurses get upset.

But yeah, I guess I could accept that it was just an anxiety related side effect. I guess that begs the question, though: when I'm offered opiate pain killers, at what point is it sensible for me to say yes?

How low were your sats going? Nurses have a tendency to get "upset", its honestly part of the job. That said, a lot of them don't understand physiology any better than paramedics despite the additional education.

Discuss the previous situation with the prescribing physician if your worried about it.

 

[Hockey]

Speaking of intranasal, someone mentioned you can get pain relief a little faster giving it IN than IV with Fentanyl because of the proximity to the brain and the receptors? Sounds good, but I'm curios to see if there is actually any science behind that?