Precedex Bolus- no loading dose.

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Pts seem oversedated in the PACU, possibly bc I have been using higher amounts?
Dexmedetomidine has a relatively long half-life after a few hours of infusion; this is why it gives such a nice intraop and postop pain control. It's not remi; you don't want to run high doses for hours and then stop it at the last minute. Stop it 30-60 minutes before wake-up, and see whether your wake-ups improve. It's also not an ideal drug to be run as solo anesthetic, unless for sedation in intubated patients.
Lately I've been doing 0.5+mcg/kg with small amount of propofol. And then I suggested using it on a bariatric case. As most of these patients besides being large, have OSA and I thought it would reduce the narcotic requirement intraoperatively and postop, and allow for a smooth wakeup. Well, my attending wanted to use remi too and bolused 1mg hydromorphone at the end, which kind of defeated the purpose. We used a BIS and kept MAC at 0.4. He got a total of 110mcg over 2hr, got a bolus dose of 40mcg and was kept at 0.2mcg/kg/hr. Although he woke up smooth, was breathing on his own, and was following commands (head lift, hand grip, answering questions, etc), my attending didn't want to extubate bc he said he looked sleepy and could stop breathing if he fell back asleep without the tube. He said it was because of the precedex, which I understand can cause oversedation, but what about the fact that he was 350lb, with OSA, and had gotten 1mg dilaudid at the end?
It was a combination, but the patient should not get 1 mg of dilaudid blindly at the end of a simple laparoscopic case. Especially if morbidly-obese with OSA.There is something called titrating to spontaneous breathing, or even giving it after wake-up. There are few good reasons for giving a relatively high dose of a long-acting opiate blindly (for the first time) just before emergence.

Did you calculate the dex dose based on the ideal or lean body weight, or on the actual one? Off-hand, I would expect precedex to not distribute in the fat tissue.
And now I'm concerned about oversedation, that I don't really want to use it, even though it makes my life so much easier in deep sedation cases, and patients seem to wake up smoother, with less narcotic requirement. What is the max total dose you would give a patient? How many hours? In a 3hr case, when would you consider shutting it off, and just running propofol? Thanks.
Oversedation is always a risk with a long infusions (context-sensitive half-time is 4 hours after an 8 hour-infusion). I would follow the recommended doses: up to 1 mcg/kg/10 min for induction, 0.2-0.7 mcg/kg/hr for maintenance, the lower the better, not as a sole anesthetic, but for opiate-sparing effects. Infusion stopped 30-60 minutes before emergence, especially for long infusions.

There is just one thing that's worse than imbalanced anesthesia: overbalanced anesthesia, with too many drugs and unpredictable combined duration of (side-)effects. Anesthesia should be about KISS (Keep It Simple Stupid). When your attending is running propofol+remi, you don't need dex during the case (although I had geniuses who were running all 3, plus some gas). When he is giving hydromorphone at the end of the case, you don't need dex at least for the last hour of the surgery, even more for long high-dose infusions (it will overlap with the opiate and increase its sedative effects). You really need to discuss the plan with your attending, and give dex only when appropriate. Better is the enemy of good enough.

Don't insist on using dex with every attending. If an attending is unfamiliar with it, the end-result might be worse than just following his more "archaic" plan. Remember that there are many ways to skin a cat in anesthesia, and residency is to try out all of them, without favoring just one way of doing things. The newer ones are not necessarily better. There are no wonder drugs in medicine (except for propofol :) ), and you might have only a limited set available at your post-residency place of work (dex might be too expensive for a private practice). Figure out what every attending is best at, and try to learn that specific talent from each.

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If we can use precedex for that, we should be able to use clonidine, too. :thinking:
 
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Great drug for peds T+As, give 0.5-1 mcg/kg after extubation with 0.1-0.2mg of Glyco.
 
Precedex might be cheaper than IV clonidine now ...? I got the impression clonidine was quite expensive
 
I have started using a bolus dose at the start of the case for some GA cases around 2 hours operating time. I do 0.3 mcg/kg in 10 mcg increments over 5-10 mins. Wake ups seem much smoother with this method but sevo has to be turned off a little earlier.
 
One of my partners uses the 0.3 mcg/kg dose to help smooth emergence. I’m guessing there’s some article or case report supporting that dose. The majority of us use 0.5/kg for kids with an emergence delirium history. 1mcg/kg for people we want a more prolonged sedation or slow emergence for some reason or combined with less opiate.
 
Frequently using it in TAVR sedations. Bolus 12mcg at a time starting as soon as we get on the table. Wait 2-3min then another 12mcg, etc usually stopping before about 0.5mcg/kg total - then start drip, usually .5mcg/kg/h. I guess you could classify that as a load or whatever, but it works well. These guys all have an art line and occasionally there's some transient hypertension (I was under the impression that there is some mild alpha1 cross reactivity) but have never had significant hypotension or bradycardia doing it this way (n=maybe 50 in old sick cardiac pts). Softer blood pressure might occur later on as the infusion's been on a while, but nothing dramatic.

I've also used it for smoothing emergence in bigger, younger men who have a h/o heavy drinking or other drug use and seem to be wound a little tight. Seems to help.
 
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Pushing precedex upfront like 0.3 ug/kg IV push works great for short cases (less than 45 min) but hypertension and bradycardia are REAL side effects to watch out for. The more you bolus quickly the more likely you will see the alpha 1 agonist effects.
 
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I'll generally use around 0.3mcg/kg bolus near the end of a case (~15-20min before emergence is planned) for patients with either severe emergence delirium or ones where there's an emphasis on them remaining fairly sedated or immobile (such as s/p MitraClip or some large lower extremity arterial access that is removed) that I do not trust to do so otherwise.
 
I'll generally use around 0.3mcg/kg bolus near the end of a case (~15-20min before emergence is planned) for patients with either severe emergence delirium or ones where there's an emphasis on them remaining fairly sedated or immobile (such as s/p MitraClip or some large lower extremity arterial access that is removed) that I do not trust to do so otherwise.


Yes, the Precedex works great for short-acting sedation. Propofol will greatly enhance propofol or any remaining volatile agent. In the elderly, the Precedex can stick around for up to 40 minutes post bolus so be prepared to deal with a sedated, elderly patient in PACU and inform the nurses of such.
 
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Agree, PACU signout is a bigger deal with precedex. And depending on dose and infusion length, have seen its effects stick around beyond the 40 minute mark, particularly hypotension in the older/sicker subset of patients.
 
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I've just started at a hospital with access to Dexmedetomidine in the OT; previously if we wanted alpha-2 we'd use clonidine, but I've never been a huge fan. A boss and I wanted to try it out so we used the standard "bolus --> infusion" and they took 5 millenia to wake up. I gather the 15minute pre-emergence bolus is a decent alternative? I'll give that a shot next time.
 
I've just started at a hospital with access to Dexmedetomidine in the OT; previously if we wanted alpha-2 we'd use clonidine, but I've never been a huge fan. A boss and I wanted to try it out so we used the standard "bolus --> infusion" and they took 5 millenia to wake up. I gather the 15minute pre-emergence bolus is a decent alternative? I'll give that a shot next time.


Okay, let's review Precedex. The first thing to know is that after you give it IV in the 0.3-0.5 ug/kg range it typically takes 15-20 minutes to wear off enough that the patient will awaken. If the patient is elderly the time can increase to 30-40 minutes. I realize that some of you think this drug is similar to Propofol in terms of duration but it isn't.

Now, if you add an infusion to the bolus dose that means the time clock doesn't start until you turn the infusion off. I like Precedex a great deal but the BP and HR fluctuations are real (Hypertension/bradycardia after a bolus followed by Hypotension sometimes requiring pressors). The more critical your patient (Low EF, Aortic Stenosis, severe MR, etc) the more careful you need to be with Precedex upfront Bolus IV (especially without an arterial line or Finger cuff beat to beat BP monitor).
 
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Dex is also a good supplement to your regional anesthesia. It isn’t necessary to place it on the nerve either.
 
This is my #1 reservation for using it as a bolus. There are plenty of documented reports of cardiac arrest with bolus delivery. Do you know how much the patient received? 20mcgs or 100mcgs?

Anyone bolusing the peds population?
I like to bolus in 4-10mcg increments (depending on if I draw it up and dilute it or just take it from the vial) up to 0.5 to 1mcg/kg. I usually do it over 20-30 minutes. Anecdotally, the patients are snoozy, calm, and have less of a narcotic need in the PACU.
 
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Since I posted this thread almost 10 years ago I've come to like 10-20 mcg boluses. Easy and effective. Not much downside.
 
In healthy subjects, dexmedetomidine reduced the propofol concentrations required for sedation and suppression of motor response by approximately one half. Propofol doses required for sedation and induction of anesthesia may have to be reduced in the presence of dexmedetomidine.

(taken from the package insert)
 
I've never bolused 1 ug/kg upfront over 2-3 minutes. That's a big dose. I have given 0.5 ug/kg/min over a few minutes and seen HR in the 30's. It is quite scary so BOLUS slowly and consider Glyco 0.2 mg IV x 1 before the bolus. 1 ug/kg is a large dose and the 1 patient I gave that to over 20 minutes had a MAC reduction of 70% (elderly guy) and then took 35 minutes to wake up in the PACU (short 40 minute case). Since then, I rarely give more than 0.5 ug/kg for cases under 45 minutes.
 
I like to combine Precedex and propofol for cases (TIVA). The combo works great and I highly recommend you give it a try.

 
You will see more hypotension with the Propofol/Precedex Combo but the level of sedation is much better and the depth of anesthesia significantly greater.

 
I've never bolused 1 ug/kg upfront over 2-3 minutes. That's a big dose. I have given 0.5 ug/kg/min over a few minutes and seen HR in the 30's. It is quite scary so BOLUS slowly and consider Glyco 0.2 mg IV x 1 before the bolus. 1 ug/kg is a large dose and the 1 patient I gave that to over 20 minutes had a MAC reduction of 70% (elderly guy) and then took 35 minutes to wake up in the PACU (short 40 minute case). Since then, I rarely give more than 0.5 ug/kg for cases under 45 minutes.
precedex is terrible for outpatients
 
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precedex is terrible for outpatients
Agreed. I never use it on an outpatient. I also try and avoid it on first start cases that go to inpatient PACU. The nurses complain that some of them stay too long and never leave PACU. I do think it’s patient dependent though.
 
precedex is terrible for outpatients
Precedex is terrible for most applications, except (preventing) delirium and reducing propofol dose. There are better drugs (e.g. ketamine).

Healthcare people always tend to forget that better is the enemy of good and K.I.S.S.

P.S. Funny I wrote something similar 5 years ago, at the top of this page.
 
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I'm using a fair amount of Precedex with Propofol. YMMV but the following statement accurately describes my experience:

"We conclude that the combination of propofol and dexmedetomidine provided cardiovascular stability without transient hypertension and bradycardia. The combination of these two agents also improved patient safety by decreasing the incidence of airway obstruction, hypoxia, spontaneous movement and agitation during deep sedation. In addition, the use of propofol and dexmedetomidine had a similar onset time as that of propofol without a delayed recovery time, and achieved higher satisfaction scores than with the use of a single drug. "

 
This is all talking about adults right? I'm doing my peds rotation and we give preceded out like candy. 0.3-0.5 mcg/kg bolus seems to work fine and the kids dont stay any longer in pacu.
 
This is all talking about adults right? I'm doing my peds rotation and we give preceded out like candy. 0.3-0.5 mcg/kg bolus seems to work fine and the kids dont stay any longer in pacu.

I found using it as an intranasal preoperative sedative worked very well on our T&A patients (compared to PO midazolam, IN midazolam, IN fentanyl...but certainly IM ketamine is always going to be your most reliable imho).

We also used it on all our outpatient peds cases as our attendings had phased out opioids. It didn’t seem to prolong wakeup or recovery but I think the same result could’ve been achieved with a long acting opioid or even propofol.
 
I like clonidine, don't feel like i need precedex for anything i do.

You don't need Precedex to do your job. But, the price has really come down to the point where it can be used more routinely in a cost effective manner.

The drug really enhances the sedation from Propofol permitting a very deep MAC/TIVA with less obstruction of the airway. On the younger patients (under age 50) there is no hangover effect when combined with Propofol (no versed or ketamine) they leave the facility quite happy. The next time you do a TIVA +/_ LMA consider adding the Precedex to your cocktail.


 
I like the fact that Precedex IV also enhances the duration of analgesia from nerve blocks. Another factor to consider if you are doing a TIVA plus a nerve block for a patient.

 
All I am saying is that look over the evidence and give it a try on an ASA 2 patient under the age of 50. The drug works extremely well and satisfaction scores are very high.

 
The drug really enhances the sedation from Propofol permitting a very deep MAC/TIVA with less obstruction of the airway. On the younger patients (under age 50) there is no hangover effect when combined with Propofol (no versed or ketamine) they leave the facility quite happy. The next time you do a TIVA +/_ LMA consider adding the Precedex to your cocktail.

What dosage ranges are you typically using when combining with propofol for MAC cases? I've never used it this way but it seems like a great application.
 
What dosage ranges are you typically using when combining with propofol for MAC cases? I've never used it this way but it seems like a great application.


Propo-Dex isa great combo. For short cases (under 45 minutes) I typically just bolus the Precedex IV upfront over a few minutes. The range is 0.3 ug/kg-1.0 ug/kg with most of my patients getting 0.5 ug/kg IV. You must watch out for severe bradycardia (and hypertension) when bolusing Precedex. The faster you bolus large amounts the more likely you will see HRs in the low 30s so be careful about the dosing. The HTN is typically nothing more than a person would see during high level exercise but the HR can get dangerously low.

"Premedication with a single intravenous dose of 0.5 μg/kg dexmedetomidine decreased the intraoperative propofol and postoperative analgesic requirements, and increased the postoperative satisfaction and Ramsay sedation scale scores considerably in patients undergoing direct laryngoscopic biopsy under total intravenous anesthesia.27 "


For longer cases you will need to start an infusion or re-bolus the Precedex or add it to the Propofol in the pump.
 
I never do this apart for endoscopy.

I am just sharing my experience with Precedex over the past 18 months. Of course, I don't use it for Gi cases of any kind.
But, for those looking for a way to really boost the sedative effects of propofol without opioids, inhalational agents, midazolam or ketamine the Precedex is a nice addition to a TIVA. The wake-ups are smooth without any hangover effects.

YMMV, but we are here to discuss anesthesia and the cost of a 2 ml ampule of precedex has come way down in price to the point you can use it for cases on a routine basis.
 
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