Going beyond 8 mg dexamethasone for PNB’s

[Burned_Out]

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Anyone here experiment with increasing the dexamethasone dose in their local anesthetic nerve block solution to increase block duration? Most studies I’ve seen stop at adding a max of 8 mg. We know that dexamethasone can crystallize if too much is added to local, but I’m not observing that when 12-14 mg is added to 20ml of 0.5% Ropivacaine or Bupivacaine. The following article states that dexamethasone is a weak vasoconstrictor and that any reports of nerve injury using dexamethasone is more likely due to the preservatives added to it. To date, no studies or case reports have shown PF-dexamethasone to be unsafe to use in PNB’s.

https://link.springer.com/content/pdf/10.1186/s42077-020-00113-7.pdf

 

[cittykat]

What is the goal?

 

[UscGhost]

What is the goal?

Mo is mo better?

 

[cittykat]

Mo is mo better?

 

[Burned_Out]

I am trying to extend the length of my blocks. Before you argue that it serves no purpose in improving outcomes, this is about patient comfort and improving their experience after surgery. We also have an ortho who insists on catheters in all his PNB's and we as a group don't like doing it because of the technical problems. We are trying to demonstrate to him that single shot PNB's can be just as effective over a similar time frame.

Our group has adapted a PNB local anesthetic cocktail that includes 0.5% Bupivacaine or Ropivacaine, 30 mcg Precedex, 8 mg dexamethasone and 0.3-0.6 mg buprenorphine. I have trialed using a higher dose of dexamethasone to see if I can improve block duration and so far it seems to be working. Nothing is more effective than decadron in prolonging blocks.

 

[cittykat]

I am trying to extend the length of my blocks. Before you argue that it serves no purpose in improving outcomes, this is about patient comfort and improving their experience after surgery. We also have an ortho who insists on catheters in all his PNB's and we as a group don't like doing it because of the technical problems. We are trying to demonstrate to him that single shot PNB's can be just as effective over a similar time frame.

Our group has adapted a PNB local anesthetic cocktail that includes 0.5% Bupivacaine or Ropivacaine, 30 mcg Precedex, 8 mg dexamethasone and 0.3-0.6 mg buprenorphine. I have trialed using a higher dose of dexamethasone to see if I can improve block duration and so far it seems to be working. Nothing is more effective than decadron in prolonging blocks.

https://associationofanaesthetists-publications.onlinelibrary.wiley.com/doi/10.1111/anae.14650

Optimal Dose of Perineural Dexamethasone to Prolong Analgesia After Brachial Plexus Blockade: A Systematic Review and Meta-analysis - PubMed

There is currently very low quality evidence that 4 mg of perineural dexamethasone represents a ceiling dose that prolongs analgesia duration by a mean period of 6 and 8 hours when combined with short-/intermediate- or long-acting local anesthetics, respectively. Additional data are needed to...

pubmed.ncbi.nlm.nih.gov

https://www.sciencedirect.com/science/article/pii/S0007091223007389

 

[Mman]

my assumption is that adding dexamethasone to a peripheral nerve block is going to decrease the likelihood of a nerve injury via anti-inflammatory effects

 

[med2010]

I am trying to extend the length of my blocks. Before you argue that it serves no purpose in improving outcomes, this is about patient comfort and improving their experience after surgery. We also have an ortho who insists on catheters in all his PNB's and we as a group don't like doing it because of the technical problems. We are trying to demonstrate to him that single shot PNB's can be just as effective over a similar time frame.

Our group has adapted a PNB local anesthetic cocktail that includes 0.5% Bupivacaine or Ropivacaine, 30 mcg Precedex, 8 mg dexamethasone and 0.3-0.6 mg buprenorphine. I have trialed using a higher dose of dexamethasone to see if I can improve block duration and so far it seems to be working. Nothing is more effective than decadron in prolonging blocks.

Just use exparel?

 

[Burned_Out]

Just use exparel?

Too expensive. Most hospitals refuse to carry it on formulary. The ones that do carry it heavily restrict it to periarticular and interscalene blocks. Those are the only 2 FDA approved indications for Exparel. There is an Exparel competitor coming on the market but no idea on cost yet.

 

[Burned_Out]

https://associationofanaesthetists-publications.onlinelibrary.wiley.com/doi/10.1111/anae.14650

Optimal Dose of Perineural Dexamethasone to Prolong Analgesia After Brachial Plexus Blockade: A Systematic Review and Meta-analysis - PubMed

There is currently very low quality evidence that 4 mg of perineural dexamethasone represents a ceiling dose that prolongs analgesia duration by a mean period of 6 and 8 hours when combined with short-/intermediate- or long-acting local anesthetics, respectively. Additional data are needed to...

pubmed.ncbi.nlm.nih.gov

https://www.sciencedirect.com/science/article/pii/S0007091223007389

View attachment 420763

Thank you for the charts. It seems like 8-10 mg of decadron is the sweet spot for optimal dosing.

 

[Ronin1]

My understanding and review of this article reflects no difference in iv versus perineural dex. We had stopped adding this to the injectate years ago.

 

[abolt18]

My understanding and review of this article reflects no difference in iv versus perineural dex. We had stopped adding this to the injectate years ago.

This was what I was taught as well. Upon looking into it further after reading this thread, it appears there is likely some small, but statistically significant increase in duration when giving perineural vs IV (3hrs). Now is 3hrs clinically significant? Tough to say. I'm sure the lines get blurred if you start adding clonidine or dexmedetomidine and/or epi to your blocks.

We don't have any preservative free dexamethasone at our hospital, so you won't catch me doing perineural at all.

 

[Gator7]

Sounds like you need to use your no words instead of adding a ton of garbage to your local.

Just use plain local if hospital doesn’t want to cover exparel. If your group decides it doesn’t want to do catheters then don’t offer catheters. Easy enough.

 

[pgg]

Sounds like you need to use your no words instead of adding a ton of garbage to your local.

Just use plain local if hospital doesn’t want to cover exparel. If your group decides it doesn’t want to do catheters then don’t offer catheters. Easy enough.

Adding dexamethasone became a thing something like ~15 years ago. It's certainly effective, and it appears safe in the 4-8 mg range (though I have some skepticism that blocks extending >>24hrs are as safe, or even really desirable in the first place).

I'm all for telling surgeons no when they come up with unreasonable or ridiculous requests, but if they want something easy and safe done, why not? We've got an orthopod who's kind of annoying, who gives lip service to evidence-based practice while doing some very silly non-evidence-based things, who pressures us to do spinals for all of his joints "because outcomes are better". The spinal vs GA debate is one in particular that makes me absolutely thoroughly exhausted because it just doesn't matter and everyone knows it just doesn't matter. But spinals aren't unreasonable (usually) and it's easy enough to do them for his cases, so I go along with it.

Save the arguments for things that matter, like the music playlist.

 

[markneil]

Adding dexamethasone became a thing something like ~15 years ago. It's certainly effective, and it appears safe in the 4-8 mg range (though I have some skepticism that blocks extending >>24hrs are as safe, or even really desirable in the first place).

I'm all for telling surgeons no when they come up with unreasonable or ridiculous requests, but if they want something easy and safe done, why not? We've got an orthopod who's kind of annoying, who gives lip service to evidence-based practice while doing some very silly non-evidence-based things, who pressures us to do spinals for all of his joints "because outcomes are better". The spinal vs GA debate is one in particular that makes me absolutely thoroughly exhausted because it just doesn't matter and everyone knows it just doesn't matter. But spinals aren't unreasonable (usually) and it's easy enough to do them for his cases, so I go along with it.

Save the arguments for things that matter, like the music playlist.

spinals to get the BP down!! DUH

 

[BLADEMDA]

Thank you for the charts. It seems like 8-10 mg of decadron is the sweet spot for optimal dosing.

Conclusions: There is currently very low quality evidence that 4 mg of perineural dexamethasone represents a ceiling dose that prolongs analgesia duration by a mean period of 6 and 8 hours when combined with short-/intermediate- or long-acting local anesthetics, respectively. Additional data are needed to explore the threshold for this effect, particularly with doses below 4 mg. The risk of neurologic complications is probably not increased (very low evidence).

 

[Burned_Out]

My understanding and review of this article reflects no difference in iv versus perineural dex. We had stopped adding this to the injectate years ago.

Not all studies bear this out.

 

[Burned_Out]

Conclusions: There is currently very low quality evidence that 4 mg of perineural dexamethasone represents a ceiling dose that prolongs analgesia duration by a mean period of 6 and 8 hours when combined with short-/intermediate- or long-acting local anesthetics, respectively. Additional data are needed to explore the threshold for this effect, particularly with doses below 4 mg. The risk of neurologic complications is probably not increased (very low evidence).

The author seems a bit unsure of his conclusions and puts a disclaimer that more data is needed. I'm just looking for better studies to validate my original question.

 

[Guillemot]

Even if these individual agents have been shown to prolong perineural blocks, is there any evidence of an additive effect by combining agents? Eg. Combined perineural dexamethasone and dexmedetomidine does not prolong analgesia beyond dexamethasone alone - NYSORA

 

[cchoukal]

Too expensive. Most hospitals refuse to carry it on formulary. The ones that do carry it heavily restrict it to periarticular and interscalene blocks. Those are the only 2 FDA approved indications for Exparel. There is an Exparel competitor coming on the market but no idea on cost yet.

And what are the FDA indications for manual admixture of unapproved drugs outside of a fume hood into a perineurial injection? I get that it sounds easy, but is actually hard, but your surgeons want a longer block, and you're experimenting with a host of unapproved polypharmacy (sorry, but small studies here and there do not capture safety endpoints) instead of making the surgeons get the hospital to approve the drug that was actually intended for this purpose. I would not be taking that route, personally.

 

[UscGhost]

The author seems a bit unsure of his conclusions and puts a disclaimer that more data is needed. I'm just looking for better studies to validate my original question.

I would just be careful. While i applaud the goal of maximizing pain relief (i also despise catheters)

Keep in mind. Blocks are always a potential source of liability. So, its additional risk if you add adjucts outside of the community standard. Dexamthasone is commonly added..but anything above 10mg may open the door for an opposing expert to cast blame.

Similarly for other adjuncts/combos. I know there are some studies that show benefits but dont want to venture too far into areas that arent well established either.

Decadron seems to help with the biggest issues of the surge of pain the occurs once block wears off

 

[BLADEMDA]

I would just be careful. While i applaud the goal of maximizing pain relief (i also despise catheters)

Keep in mind. Blocks are always a potential source of liability. So, its additional risk if you add adjucts outside of the community standard. Dexamthasone is commonly added..but anything above 10mg may open the door for an opposing expert to cast blame.

Similarly for other adjuncts/combos. I know there are some studies that show benefits but dont want to venture too far into areas that arent well established either.

Decadron seems to help with the biggest issues of the surge of pain the occurs once block wears off

IMHO and dedades of experience doing thousands of nerve blocks I recommend KISS. If you are going to use Decadron keep the dosage under 10 mg and I routinely use just 4-8 mg. AS for Precedex 30-50 ug I found it does add another 1-2 hours to the block but at what cost? Hypotension and bradycardia are possible and I try to avoid those issues in an outpatient setting. Buprenorphine also can add 1-2 hours to the block. These days I use either straight local anesthetic or local anesthetic with 4-8 mg decadron added.

If you do enough nerve blocks (N= 1,000+) the odds are you will have a complication postop. So for legal reasons as well as safety your injection should conform to the "standard of care" in your community. I rest much easier knowing my blocks are pretty much standard with either Exparel, Bup/Rop, or Bup/Rop with decadron 4-8 mg. A well placed block will deliver around 16-18 hours of post op pain relief and sometimes 24 hours. My last patient told me that his block wore off after 30 hours and I used 0.5% Bup with decadron 6 mg.

 

[Burned_Out]

And what are the FDA indications for manual admixture of unapproved drugs outside of a fume hood into a perineurial injection? I get that it sounds easy, but is actually hard, but your surgeons want a longer block, and you're experimenting with a host of unapproved polypharmacy (sorry, but small studies here and there do not capture safety endpoints) instead of making the surgeons get the hospital to approve the drug that was actually intended for this purpose. I would not be taking that route, personally.

I don't think you'll convince anyone who uses dexamethasone in their nerve blocks to go back to the old ways. We've come to realize that adding epinephrine to local for PNB's, like how we use to do it in the old days, is riskier than we were lead to believe. The cat's out of the bag for at least the last 15 years with respect to perineural dexamethasone. If you look at what they put into Exparel, it's nothing more than a steroid encapsulated bupivacaine molecule. I will argue that Exparel is riskier to use because of the risk of premature release of the liposomal bupivacaine molecule due to excess bupivacaine. As for the other adjuvants included in local solutions, I went to the ASRA meeting in 2019 and they were already advocating that perineural buprenorphine was safe and effective.

 

[BLADEMDA]

PGG is correct in his opinion that all nerve blocks wear off and why do they need to last more than 24 hours? Why not just add the new drug Journavx plus NSAIDS like Celebrex and Tylenol post op? I used to think all my blocks had to last 24+ hours postop but the older and wiser I get the more I realize that safety and simplicity are much more important than duration for patient care. 6 months later patients won't care whether their block lasted 18 hours vs 24 hours but they will care if they develop a postop neuropathy.

https://www.journavx.com/