[snakebitten]

I will use 10 mcg/kg on a 20 minute tonsillectomy without problems (Without Narcan). Occasionally the patients will have nausea (last PI study was 3%). Our PACU times have DECREASED since our team has decreased the inhaled agents. I haven't cracked a Narcan vial in 5 years. And about depending on the BIS monitor..We just started using it 3 months ago and do NOT intend on buying one. It just confirmed what we were practicing. I personally do not like the monitors. Just because the reading is 50 does not mean you have Analgesia on board. I have had them jump with "general Anesthetic numbers" By the way the makers of the PSARRAY 4000 and the BIS monitor sell their equipment with the idea of how much agent you do NOT need. They will not stand by their numbers "making SURE your patient is asleep". I believe in the older studies that 1/4 MAC of vapors with nitrous is amnestic. The least amount of vapor the better. Sufenta on the other hand is different...The case has to be at least an hour long for a Sufenta bolus...Even then you will have a comfortable, responsive patient who will not be breathing. Enough said for now ..gotta start another case

Originally Posted by jwk

I agree with gotosleepy - 10-15mcg/kg is too much for a lot of cases. 20cc of fentanyl up front on a 1hr TAH = Narcan at the end. I'm curious what kind of PACU discharge times you have with this much narcotic.

And keep depending on that BIS monitor - you'll get burned someday. It's that "...You would be suprised at how little gas/nitrous you need for amnestic levels..." that can get you in big trouble. The idea is NOT to see how little agent you can get by with. It's to make SURE your patient is asleep, which of course the BIS does not do. Any monitor that will show a bowl of Jello is asleep is not one I want to use. And I wasn't aware the BIS was an amnesia monitor as well as an awareness monitor.

[skipaway]

Originally Posted by snakebitten

OK I am new here, but a CRNA for 10 years...I use induction doses of fentanyl 10-15 ug/kg, 50 of propofol, (NO VERSED!!-which WILL hose your wakeup) muscle relaxant of choice usuallly Mivacrap and whiffs of desflurane-even for 30 minute cases. I have never had a problem with bucking or pain on extubation. I always give decadron 8mg and Zofran 4mg to prevent any nausea...Give it a try

snakebitten:
Do you dose on actual or IBW?


skipaway

[gaspassah]

snake i was wondering if you have even experienced the "rigid chest" syndrome from pushing that much fent. not that i dont like the idea of alot of narcs. however is this rigid chest thing a concern when you use that much fent. or is it more based on the speed at which you push it?
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[TraumaNurse]

I always thought the 'Rigid Chest' was from rapid Fentanyl bolus, not necessarily the amount. That said, in almost 10 years of critical care, I don't think I have ever seen the rigid chest phenomena from Fentanyl....I have only read about it. I also hope I do not see it any time soon!

[snakebitten]

Never had a rigid chest that Sux won't cure. Obviously I would never push all those narcs without wanting to secure the airway. Never had rigid chest with Fentanyl but Sufenta/Alfenta on the other hand will cause a rigid chest in large doses.
I use the actual weight for narcotic boluses. Fat is a great reservoir for Fentanyl. Again, every situation and patient is different. I use these large amounts on ASA 1-2 without COPD, Hx of severe sleep apnea etc.. ..

Originally Posted by TraumaNurse

I always thought the 'Rigid Chest' was from rapid Fentanyl bolus, not necessarily the amount. That said, in almost 10 years of critical care, I don't think I have ever seen the rigid chest phenomena from Fentanyl....I have only read about it. I also hope I do not see it any time soon!

[georgia_aa]

Originally Posted by snakebitten

Never had a rigid chest that Sux won't cure. Obviously I would never push all those narcs without wanting to secure the airway. Never had rigid chest with Fentanyl but Sufenta/Alfenta on the other hand will cause a rigid chest in large doses.
I use the actual weight for narcotic boluses. Fat is a great reservoir for Fentanyl. Again, every situation and patient is different. I use these large amounts on ASA 1-2 without COPD, Hx of severe sleep apnea etc.. ..

Snakebitten - you are exactly 100% dead-on-the-money correct in how you are dosing your Fentanyl. One of the attendings that I work with on an almost daily basis did much of the early animal studies on the pharmacokinetics of Fentanyl and wrote the Opiod chapter in Barash when I was a student in 1990. He taught me that dosing Fentanyl 8-12 mcg/kg at induction provided very predictable results and stable hemodynamics. I only dose in this manner if I'm fairly confidant that the case will last 1 hour or more although I have always been able to wake up patients when I have misjudged. Like you, I can't remember the time that I had to resort to Narcan. My typical regimen for TAH as an example is 500 - 700 mcg Fent on induction followed in about 30 min by 10mg MSO4. As the Fentanyl levels start to tail off during the second half hour of the case, the MSO4 is reaching peak efficacy. The end result is a great preemptive analgesia anesthetic with the patient waking up very quickly and absolutely pain free. PACU time is paradoxically decreased with this technique because the nurses are not having to give pain meds to keep the patient comfortable. I have been using this technique for many years and constantly get the question - "what is it that you are doing different??" because my patients wake up so smoothly and quickly and are easy to recover.

Pre-emptive analgesia is the key to a truely elegant anesthetic. Dose your narcotic preemptively instead of reactively (BP and HR changes) and you will get a consistently smooth anesthetic course and a really great wakeup.

[charles-thor]

I have read that low does of ketamine (5-20mg iv) provide profound analgesia and may act to decrease narcotic requirements. Does anyone out there do this?

[gaspassah]

I always thought the 'Rigid Chest' was from rapid Fentanyl bolus, not necessarily the amount

well exactly, if your pushing 800 mcg for induction there is only so much time you have before you need to put the tube in. i've heard of rigid chest with 200 mcg, when pushed fast. i've never seen it.
so this brings a good point, how fast do you push 800 mcg for induction?

[Gotosleepy]

while i like the idea of high-dose narcotics - giving a patient 700mcg of fentanyl for a 20 minute case? give me a break.... while i agree the less volatile you use, the better the wake up, I find that using such high doses of fentanyl unnecessary....

- don't tell me to read the literature on context sensitive half-life when you clearly don't understand context sensitive half-life: it is the time for plasma concentration to fall by 50% following steady-state infusion and constant blood levels (which for most drugs is about 2-3 hours)... which is totally unrelated to single-dose boluses at the beginning of the case. Not to mention that the context sensitive half-life of fentanyl after infusion is >100 mins!!! and in some reports can be close to 400-500 minutes! Which is the main reason that a fentanyl infusion is pointless, might as well just use a dilaudid infusion.

[rsh3rn]

I work in recovery the best wake ups I've seen were with bolus doses of fent up front then using small amts every 15 mins to prevent the drug from wearing off and switching to morphine near the end for the longer pain relief effects, and always versed at the beginning of the case waking up in recovery is scary best to be sleepy and forgetful. Our CRNA does a great job with this I've never had a single respiratory or pain issue with his work