Local anesthetic mixtures for surgical blocks

[broken pager]

I'm curious to know what mixtures everyone is using for their surgical blocks. Our group typically use a combination of ropivicaine and mepivicaine, and this has worked well for us, as it acts quickly and gives some longer acting coverage as well. However, some of the sites we cover do not stock any mepivicaine.

Are any of you routinely using lidocaine for your PNB's instead?

What about for your quick or ultra short cases?

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[abolt18]

I'm curious to know what mixtures everyone is using for their surgical blocks. Our group typically use a combination of ropivicaine and mepivicaine, and this has worked well for us, as it acts quickly and gives some longer acting coverage as well. However, some of the sites we cover do not stock any mepivicaine.

Are any of you routinely using lidocaine for your PNB's instead?

What about for your quick or ultra short cases?

We'll use 2% lido and .5% ropi.

 

[deleted875186]

Also curious about this.

Does 0.25% bupi provide a dense enough block to do a case under MAC? How long before the case do you have o block them?

I’ve heard mixed things about mixing local anesthetics. I thought the block ended up similar to if the long acting local had been used.

 

[DM27]

We use 0.5% Ropi or Bupi, provider preference between those two. We have Mepiv 1.5% and Lido 2.0%, used interchangeably as well based on provider preference.

I prefer Mepiv and Ropi (separate and together) but have also used Lico and Bupi (separate and together) fairly often as well and honestly couldn’t really notice any differences.

In terms of mixing them, there are 2 studies that I am aware of out there that basically found when you mix a short and a long the onset time tends to resemble the slower of the two and the block durations tends to be somewhat shorter than the long acting alone.

I personally will use a separate syringe of a fast acting (lido or Mepiv) and then use a syringe of the long acting without mixing them. From my purely anecdotal experience the block does start working much faster when done this way, in some instances it will start kicking it even as I am finishing the long acting injection. When I used to mix them I didn’t really notice a difference in terms of a quicker onset time.

I don’t have any experience using 0.25% for a surgical block, if it is possible I would assume there is minimal motor component and that the onset time and density are likely quite variable, I would assume it needs 20 minutes to set in to whatever it’s going to be.

The Effect of Mixing 1.5% Mepivacaine and 0.5% Bupivacaine... : Anesthesia & Analgesia

es bupivacaine and in a longer duration of blockade than does mepivacaine. METHODS: Sixty-four patients undergoing arthroscopic shoulder surgery (ages 18 to 65 years; ASA physical status I–II) with ultrasound-guided interscalene brachial plexus block as the sole anesthetic were studied. The...

journals.lww.com

 

[thinkorswim]

In residency, we would use a mixture of either lidocaine or mepivacaine with bupivacaine. I never quite understood the point of giving a patient anything that'll shorten the duration of the block, but who was I to argue.

In practice now, I use only 0.5% bupivacaine or 0.5% ropivacaine for every block (with a few exceptions). Blocks are done in the preop area, so there is more than enough time for it to take effect.

 

[Noyac]

We use 0.5% Ropi or Bupi, provider preference between those two. We have Mepiv 1.5% and Lido 2.0%, used interchangeably as well based on provider preference.

I prefer Mepiv and Ropi (separate and together) but have also used Lico and Bupi (separate and together) fairly often as well and honestly couldn’t really notice any differences.

In terms of mixing them, there are 2 studies that I am aware of out there that basically found when you mix a short and a long the onset time tends to resemble the slower of the two and the block durations tends to be somewhat shorter than the long acting alone.

I personally will use a separate syringe of a fast acting (lido or Mepiv) and then use a syringe of the long acting without mixing them. From my purely anecdotal experience the block does start working much faster when done this way, in some instances it will start kicking it even as I am finishing the long acting injection. When I used to mix them I didn’t really notice a difference in terms of a quicker onset time.

I don’t have any experience using 0.25% for a surgical block, if it is possible I would assume there is minimal motor component and that the onset time and density are likely quite variable, I would assume it needs 20 minutes to set in to whatever it’s going to be.

The Effect of Mixing 1.5% Mepivacaine and 0.5% Bupivacaine... : Anesthesia & Analgesia

es bupivacaine and in a longer duration of blockade than does mepivacaine. METHODS: Sixty-four patients undergoing arthroscopic shoulder surgery (ages 18 to 65 years; ASA physical status I–II) with ultrasound-guided interscalene brachial plexus block as the sole anesthetic were studied. The...

journals.lww.com

Please do yourself and every other physician a favor and stop referring to doctors as providers.

 

[Noyac]

In residency, we would use a mixture of either lidocaine or mepivacaine with bupivacaine. I never quite understood the point of giving a patient anything that'll shorten the duration of the block, but who was I to argue.

In practice now, I use only 0.5% bupivacaine or 0.5% ropivacaine for every block (with a few exceptions). Blocks are done in the preop area, so there is more than enough time for it to take effect.

I have been mixing mepiv and ropiv for over 15 yrs. The blocks still last about 24hrs. I am not interested in a block that lasts longer than this.

 

[Noyac]

OP, I use mepiv 1.5% when available. Lido 2% when not.

 

[BLADEMDA]

Also curious about this.

Does 0.25% bupi provide a dense enough block to do a case under MAC? How long before the case do you have o block them?

I’ve heard mixed things about mixing local anesthetics. I thought the block ended up similar to if the long acting local had been used.

Anesth Analg. 2009 Feb;108(2):641-9. doi: 10.1213/ane.0b013e31819237f8.
A comparison of the pharmacodynamics and pharmacokinetics of bupivacaine, ropivacaine (with epinephrine) and their equal volume mixtures with lidocaine used for femoral and sciatic nerve blocks: a double-blind randomized study.
Cuvillon P1, Nouvellon E, Ripart J, Boyer JC, Dehour L, Mahamat A, L'hermite J, Boisson C, Vialles N, Lefrant JY, de La Coussaye JE.
Author information

Abstract
BACKGROUND:
Mixtures of lidocaine with a long-acting local anesthetic are commonly used for peripheral nerve block. Few data are available regarding the safety, efficacy, or pharmacokinetics of mixtures of local anesthetics. In the current study, we compared the effects of bupivacaine 0.5% or ropivacaine 0.75% alone or in a mixed solution of equal volumes of bupivacaine 0.5% and lidocaine 2% or ropivacaine 0.75% and lidocaine 2% for surgery after femoral-sciatic peripheral nerve block. The primary end point was onset time.
METHODS:
In a double-blind, randomized study, 82 adults scheduled for lower limb surgery received a sciatic (20 mL) and femoral (20 mL) peripheral nerve block with 0.5% bupivacaine (200 mg), a mixture of 0.5% bupivacaine 20 mL (100 mg) with 2% lidocaine (400 mg), 0.75% ropivacaine (300 mg) or a mixture of 0.75% ropivacaine 20 mL (150 mg) with 2% lidocaine (400 mg). Each solution contained epinephrine 1:200,000. Times to perform blocks, onset times (end of injection to complete sensory and motor block), duration of sensory and motor block, and morphine consumption via IV patient-controlled analgesia were compared. Venous blood samples of 5 mL were collected for determination of drug concentration at 0, 5, 15, 30, 45, 60, and 90 min after placement of the block.
RESULTS:
Patient demographics and surgical times were similar for all four groups. Sciatic onset times (sensory and motor block) were reduced by combining lidocaine with the long-acting local anesthetic. The onset of bupivacaine-lidocaine was 16 +/- 9 min versus 28 +/- 12 min for bupivacaine alone. The onset of ropivacaine-lidocaine was 16 +/- 12 min versus 23 +/- 12 for ropivacaine alone. Sensory blocks were complete for all patients within 40 min for those receiving bupivacaine-lidocaine versus 60 min for those receiving bupivacaine alone and 30 min for those receiving ropivacaine-lidocaine versus 40 min for those receiving ropivacaine alone (P < 0.05). Duration of sensory and motor block was significantly shorter in mixture groups. There was no difference among groups for visual analog scale pain scores and morphine consumption during the 48 h postoperative period, except for bupivacaine alone (median: 9 mg) versus bupivacaine-lidocaine mixture (15 mg), P < 0.01. There was no difference in the incidence of adverse events among groups. Plasma concentrations of bupivacaine and ropivacaine were higher, and remained elevated longer, in patients who received only the long-acting local anesthetic compared to patients who received the mixture of long-acting local anesthetic with lidocaine (P < 0.01).
CONCLUSION:
Mixtures of long-acting local anesthetics with lidocaine induced faster onset blocks of decreased duration. Whether there is a safety benefit is unclear, as the benefit of a decreased concentration of long-acting local anesthetic may be offset by the presence of a significant plasma concentration of lidocaine

 

[JWebar]

Im still on the fence on this. Tend to use Bupi .5% + Lido 2% just cause in a busy environment 10 mins less of onset can make the difference. Algo putting perineural Dexamethasone and getting ~20–24 hrs of duration for a single shot. As someone else already said, if the surgery doesn't merit a catheter, having a single shot lasting more than 24 hrs can be detrimental. The dead limb sensation can be very discomforting (talking from personal experience).

 

[Hoya11]

I'm curious to know what mixtures everyone is using for their surgical blocks. Our group typically use a combination of ropivicaine and mepivicaine, and this has worked well for us, as it acts quickly and gives some longer acting coverage as well. However, some of the sites we cover do not stock any mepivicaine.

Are any of you routinely using lidocaine for your PNB's instead?

What about for your quick or ultra short cases?

I use 0.5% bupi with epi and decadron every time. Never had any issues with the block not setting up in time.

What ultra short cases are you doing that require a block?

Surgeons are very happy with the long lasting blocks and so are the patients. I typically get 36hrs.

My goal is to make the block be very dense and last as long as possible.

I am not entirely understanding the desire to have the block wear off, sure its a weird feeling but its covering intense pain so why is 36hrs too long? admittedly I have never had one myself thankfully.

 

[Mman]

i don't mix locals. If I want long acting I use Ropi or Bupi and if I want fast and short I use Mepi.

 

[ethilo]

Perineural dexamethasone shortens block onset time and prolongs analgesia significantly. I expect 15 min for incision time after a supraclav single shot using 30 mL ropi 0.5% + dex 8mg. Here's some light reading to consider:

With lido 1.5% + 1:200k epi +/- 8 mg dex, the onset of sensory and motor blockade (13.4±2.8 vs. 16.0±2.3 min and 16.0±2.7 vs. 18.7±2.8 min, respectively) were significantly more rapid in the dexamethasone group than in the control group (P=0.001). The duration of sensory and motor blockade (326±58.6 vs. 159±20.1 and 290.6±52.7 vs. 135.5±20.3 min, respectively) Effect of dexamethasone added to lidocaine in supraclavicular brachial plexus block: A prospective, randomised, double-blind study

The MEV90 of supraclavicular block as tested for successful block by 30 minutes was 32mL of lido 1.5% with 1:200k epi. Minimum effective volume of lidocaine for ultrasound-guided supraclavicular block. - PubMed - NCBI

Effect of Dexamethasone added to lidocaine in Supraclavicular brachial plexus block
Effect of dexamethasone added to lidocaine in supraclavicular brachial plexus block: A prospective, randomised, double-blind study

Effect of Dexamethasone on Characteristics of Supraclavicular Nerve Block with Bupivacaine and Ropivacaine: A Prospective, Double-blind, Randomized Control Trial Effect of Dexamethasone on Characteristics of Supraclavicular Nerve Block with Bupivacaine and Ropivacaine: A Prospective, Double-blind, Randomized Control Trial

 

[DrZzZz]

Also curious about this.

Does 0.25% bupi provide a dense enough block to do a case under MAC? How long before the case do you have o block them?

I’ve heard mixed things about mixing local anesthetics. I thought the block ended up similar to if the long acting local had been used.

In training, that was virtually all we used. Did it at a busy ortho center, worked great, very rarely had to convert to GA.

 

[linkin06]

30 cc for a supraclav sounds like on the higher side. I didn't see it on quick glance, but have you seen higher phrenic nerve blockade too?

 

[JWebar]

30 cc for a supraclav sounds like on the higher side. I didn't see it on quick glance, but have you seen higher phrenic nerve blockade too?

32 mL is the MEV90 for Supraclav (and 35 mL for Infraclav). If you want that consistency and are using them as your main source of anesthesia (surgical block), those are the volumes you want. With an ultrasound guided technique you get ~40% of phrenic nerve blockade, so that has to be taken into account for sure.

 

[ethilo]

JWebar is right on point: 32mL. I just choose 30 because it fills the 30cc syringe. You accept the phrenic nerve blockade as though it comes with the package. Based on NYSORAs article about toxicity to nerves, I avoid epi with anything more proximal than axillary block, also that epi hasn't been shown to speed onset or prolong duration with ropi in the upper extremity. 95% certainty for successful incision blockade in 15 mins with my ropi+dex plan, supported by evidence. Don't know if you can get much faster than that with PNBs.

 

[ethilo]

30 cc for a supraclav sounds like on the higher side. I didn't see it on quick glance, but have you seen higher phrenic nerve blockade too?

It can certainly be tough in smaller people but 150mg is 2/kg in a 75kg person so still within the realm of safe for LAST, and the sooner you just assume all supraclavs cause phrenic nerve palsy, you'll get over the concern about whether or not it'll happen at all.

 

[dhb]

10cc for a SCB should be enough if you know what you're doing.

 

[nimbus]

10cc for a SCB should be enough if you know what you're doing.

How much duration do you get with 10ml?

 

[Noyac]

I am not entirely understanding the desire to have the block wear off, sure its a weird feeling but its covering intense pain so why is 36hrs too long? admittedly I have never had one myself thankfully.

Have you had any surgeries like we are talking about? I’ve had them all, shoulder, ACL, THA, the list goes on. POD#1 is the time to start PT. You can’t participate in PT if your limb is totally numb. You need to get the muscles firing and any time spent waiting for this to happen is wasted time. That wasted time can lead to complications later as well. Things like frozen joints, increased pain. It is my opinion that people that start PT early are better prepared to deal with the recovery process than the ones that wait. ROM is extremely important in the first few days. This can occur with a block but participation is important.

At least, this is how I approach the process.

 

[Noyac]

In training, that was virtually all we used. Did it at a busy ortho center, worked great, very rarely had to convert to GA.

Training is a very different environment. You feel like you are rushed but in reality things take forever. Even the time from entering the OR til incision is forever. This was why you got away with this so often. I don’t disagree that it is doable. Just not as doable in my environment. If I get freed up by a partner then I can take my time. If not I have 10 min to wake the pt up, get them to PACU and interview/block the next pt. Incision is shortly after.

 

[DrZzZz]

Training is a very different environment. You feel like you are rushed but in reality things take forever. Even the time from entering the OR til incision is forever. This was why you got away with this so often. I don’t disagree that it is doable. Just not as doable in my environment. If I get freed up by a partner then I can take my time. If not I have 10 min to wake the pt up, get them to PACU and interview/block the next pt. Incision is shortly after.

I agree to a point. Training was no question different than private practice. But that ortho center wasn't remotely run like the academic hospital. It was a business. We did our best to time blocks to be done 15 min before heading back to the OR, but there were many instances where the OR nurse was standing outside the preop bay impatiently waiting for you to finish your block so they could head back to the OR with the patient. The OR staff got to leave when their room finished, so there actually was incentive to get things done quickly. And even in those instances where the block needle was being pulled out of the patient as the nurse was unlocking the bed to head to the OR, very rare we needed GA because of that. Transport to the room, surgical prep, time out, etc. That gave you 10-15 min for the block to set up and the vast majority of the time, that was enough, even with 0.25% bupi (usually with epi).

That setting was one of the best parts about my training, and I think it really prepared me for my busy private practice that the academic part of residency couldn't provide in the same fashion.

 

[JWebar]

Have you had any surgeries like we are talking about? I’ve had them all, shoulder, ACL, THA, the list goes on. POD#1 is the time to start PT. You can’t participate in PT if your limb is totally numb. You need to get the muscles firing and any time spent waiting for this to happen is wasted time. That wasted time can lead to complications later as well. Things like frozen joints, increased pain. It is my opinion that people that start PT early are better prepared to deal with the recovery process than the ones that wait. ROM is extremely important in the first few days. This can occur with a block but participation is important.

At least, this is how I approach the process.

This is a very good point. Surgeons are pressuring us more and more about the muscle weakness, and I think they are right. Early PT is crucial in the recovery of most ortho procedures (ando also getting pts out of the hospital). They dont take into account though that severe pain does produce muscle weakness by an inhibition mechanism I cant quite remember 😛

I can tell you from my own experience (UCL repair done with infraclav, lasted around 26 hrs) that the feeling of a dead limb is the worst hahaha. I had heard that same thing from some patients but I always thought they were exaggerating. My take is that if the surgery really is painful, then by all means the more the merrier (catheter if needed), but if not, then a short block thats gets you through the first 12–16 hrs is probably better.

 

[JWebar]

JWebar is right on point: 32mL. I just choose 30 because it fills the 30cc syringe. You accept the phrenic nerve blockade as though it comes with the package. Based on NYSORAs article about toxicity to nerves, I avoid epi with anything more proximal than axillary block, also that epi hasn't been shown to speed onset or prolong duration with ropi in the upper extremity. 95% certainty for successful incision blockade in 15 mins with my ropi+dex plan, supported by evidence. Don't know if you can get much faster than that with PNBs.

Thx! I don't really agree with your take on epinephrine though. As you said, Epi doesn't really help the block dynamics that much but it does decrease the vascular absorption. We are using big volumes and a lot of local and only doing a very basic calculation of "maximum dose" that can't be applied for every patient (ASA 3 absolutely has more risk of toxicity from LA, but we don't know how much). I think risk of LAST >>>> nerve injury. With ultrasound and good practice intrafascicular injection is very unlikely, and is there is a neurological complication postop, most likely is multifactorial (and surgery related). And also helps you to identify vascular injection! 😛

 

[ethilo]

It's a good point, I've gone back and forth about including epi to help test for intravascular injection. They said something about 2.5mcg/kg is the safe dose for epi. My avoidance of epi is certainly taking things to an extreme and not necessarily the right thing to do. Practice practice practice!

 

[Hoya11]

This is a very good point. Surgeons are pressuring us more and more about the muscle weakness, and I think they are right. Early PT is crucial in the recovery of most ortho procedures (ando also getting pts out of the hospital). They dont take into account though that severe pain does produce muscle weakness by an inhibition mechanism I cant quite remember 😛

I can tell you from my own experience (UCL repair done with infraclav, lasted around 26 hrs) that the feeling of a dead limb is the worst hahaha. I had heard that same thing from some patients but I always thought they were exaggerating. My take is that if the surgery really is painful, then by all means the more the merrier (catheter if needed), but if not, then a short block thats gets you through the first 12–16 hrs is probably better.

Is there any actual data that PT on POD1 vs POD2 has any significant difference ?

 

[dhb]

How much duration do you get with 10ml?

20-24h with dexa

 

[anbuitachi]

Training is a very different environment. You feel like you are rushed but in reality things take forever. Even the time from entering the OR til incision is forever. This was why you got away with this so often. I don’t disagree that it is doable. Just not as doable in my environment. If I get freed up by a partner then I can take my time. If not I have 10 min to wake the pt up, get them to PACU and interview/block the next pt. Incision is shortly after.

So you use lido for most block cases?

How long does bupi and ropi take if lido takes 12 to 17 minutes? 30?

 

[Arch Guillotti]

It's a good point, I've gone back and forth about including epi to help test for intravascular injection.

I just watch for the local to spread on the screen.

 

[DM27]

Is there any actual data that PT on POD1 vs POD2 has any significant difference ?

We do day of surgery PT and have found they tend to be discharged earlier without issues. These were some of the studies that helped start this initiative. The first article examines POD0 vs. POD1 and you could extrapolate that a similar outcome would likely be reached using POD1 vs. POD2.

Initiating Physical Therapy on the Day of Surgery Decreases Length of Stay Without Compromising Functional Outcomes Following Total Hip Arthroplasty

https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0178295&type=printable

ScienceDirect

None of this evidence is independently amazing, but it correlates to the somewhat logical conclusion of "the sooner you start the activity pathway to discharge the sooner discharge will occur" without demonstrating any evidence of setbacks or complications.

 

[Hoya11]

We do day of surgery PT and have found they tend to be discharged earlier without issues. These were some of the studies that helped start this initiative. The first article examines POD0 vs. POD1 and you could extrapolate that a similar outcome would likely be reached using POD1 vs. POD2.

Initiating Physical Therapy on the Day of Surgery Decreases Length of Stay Without Compromising Functional Outcomes Following Total Hip Arthroplasty

https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0178295&type=printable

ScienceDirect

None of this evidence is independently amazing, but it correlates to the somewhat logical conclusion of "the sooner you start the activity pathway to discharge the sooner discharge will occur" without demonstrating any evidence of setbacks or complications.

A hip is not a knee or shoulder where there is a dense block in place.

And also, the reason they are being discharged earlier is just because they are being discharged earlier. Just DC them on POD 0 or 1 anyhow and give them Home PT when the block wears off. The lack of ability to do PT due to a block keeps them in the hospital? "Length of Stay" is not exactly the clinical end point im interested in, as its determined by Ortho PAs and bean counters moreso than our anesthetic mixture. Lots of these are done as outpatient anyhow.

I believe that with a long, dense block well into 36+ hours, the severe pain signals not reaching the brain and the lack of the resulting sympathetic surge from the pain make the whole experience less of a stress to the homeostasis of the body. Less pain, less pain medicines, less changes to the body. By the time the block wears off you are in the mild-moderate stage of pain, thats the way I think about it..

 

[Noyac]

So you use lido for most block cases?

How long does bupi and ropi take if lido takes 12 to 17 minutes? 30?

No, I mostly use just ropiv.
I only use mepiv or lido when I have very little time and I’m not putting the pt to sleep.
With that said, yesterday I did a popliteal block with lido only for one of our nurses that didn’t want to go to sleep and didn’t want to be numb all day.
Every case is different.