Testing for RFA

[Dansk2011]

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I learned to at least motor stim with rfa and certainly is standard of care as far as I'm concerned but I know of a few people including someone I work with who does not stim. burns off just positioning. Anyone seeing or doing this? Certainly cuts down on time but I'd imagine not worth the risk/liability.

 

[RoloTomassi]

Not worth it. I get motor stim not that uncommonly because I try to get pretty deep, close to foramen on lumbar, anterior pillar on cervical.

Not sure how everyone does it but I turn on stim on one probe, then just hold that one and touch it to each cannula for a few seconds each. It's pretty fast.

 

[nvrsumr]

Don’t know where stim button is

 

[callmeanesthesia]

Rarely have to adjust but I do it while waiting for the local to kick in, so it doesn’t add any time. Same as Rolo, put probe 1 in needle 3, start the motor stim, then move it to 2 then 1.

 

[MD87]

I use motor. I think it's especially helpful in scoli patients where getting a good lateral is difficult. I prefer to be too deep on these and pull back if I get any motor stim. For whatever reason, I most often get leg movement at my L3 MB needle. I inject 2% then connect all my probes. Even after injecting 2% I still get multif twitch.

 

[BobBarker]

I think motor stim is clearly helpful. I got stim on a sacral RFA on a morbidly obese patient the other day. It was really hard to see anything and I was more medial than I thought.

 

[1 Up]

I used to not stim, but then I resumed when I started using Coolief. I'm paranoid about the bigger burn lesion. I only stim to avoid the nerve root. I don't care about multifidus stim.

 

[Dansk2011]

I put about 0.5-1 cc of 2% lido before I lesion. Are you all numbing before or after stim? Not sure it adds much more time but trying to cut down on anything that I can without jeopardizing safety.

 

[Dansk2011]

I use motor. I think it's especially helpful in scoli patients where getting a good lateral is difficult. I prefer to be too deep on these and pull back if I get any motor stim. For whatever reason, I most often get leg movement at my L3 MB needle. I inject 2% then connect all my probes. Even after injecting 2% I still get multif twitch.

Missed this somehow. Appreciate it.

 

[callmeanesthesia]

I put about 0.5-1 cc of 2% lido before I lesion. Are you all numbing before or after stim? Not sure it adds much more time but trying to cut down on anything that I can without jeopardizing safety.

Time to onset of local anesthetic is proportional to diameter of the nerves. It would take at least several minutes to penetrate a spinal nerve root to create a motor block.

 

[Taus]

I put a cc of 2% on each medial branch before I motor test. Motor testing is for the lawyers. Gives me something to do while the 2% kicks in before I burn.

 

[BobBarker]

I put a cc of 2% on each medial branch before I motor test. Motor testing is for the lawyers. Gives me something to do while the 2% kicks in before I burn.

Yes, this is what I do as well. We didn’t have any 2% lido handy yesterday and I had a .5% multi-use bupi nearby and I used it on one case. The patient said he couldn’t feel the burn at all.

 

[SSdoc33]

Time to onset of local anesthetic is proportional to diameter of the nerves. It would take at least several minutes to penetrate a spinal nerve root to create a motor block.

exactly. and the medial branches are tiny. requires seconds, not minutes to onset.

bogduk used to preach that stim was not necessary, but still do motor. it helps with safety and accuracy or needle placement

 

[Taus]

exactly. and the medial branches are tiny. requires seconds, not minutes to onset.

bogduk used to preach that stim was not necessary, but still do motor. it helps with safety and accuracy or needle placement

Perhaps, but my patients shriek when I turn it on right after injecting the local… And feel almost nothing if I give it a couple minutes. It’s not just the nerves, it’s the surrounding soft tissue, periosteum, etc.

 

[SSdoc33]

Perhaps, but my patients shriek when I turn it on right after injecting the local… And feel almost nothing if I give it a couple minutes. It’s not just the nerves, it’s the surrounding soft tissue, periosteum, etc.

a "couple of minutes" is insane. try giving it 20 seconds. you will not notice a difference. those minutes add up

 

[Ferrismonk]

I do motor stim. It literally takes about 15 seconds to do all levels. Why skip it?

I numb skin with 2%, wait 1-2 minutes (way overkill), place cannulas, motor stiim, inject 1mL 2%, wait 2 minutes (way overkill), then then burn. I can do a bilateral RF in 20 minutes this way. Could I shorten it to 10 by cutting corners? Sure. Is it worth it? No.

 

[BobBarker]

It isn’t cutting corners but it is wasting your time with the waiting on the skin local. Inject yourself and see. It is instant.

 

[bedrock]

It isn’t cutting corners but it is wasting your time with the waiting on the skin local. Inject yourself and see. It is instant.

a "couple of minutes" is insane. try giving it 20 seconds. you will not notice a difference. those minutes add up

Agree with both of these guys. It doesn’t take minutes only seconds for 2% lido to make a structure numb.

 

[Ronin1]

They don’t feel a 20 gauge right after the local but I use all 18s and they will whine if u don’t wait a few seconds. I usually inject all six skin sites then go back to where I started to place cannulas. An easy bilateral RFA is 10-12 minutes.

 

[MD87]

They don’t feel a 20 gauge right after the local but I use all 18s and they will whine if u don’t wait a few seconds. I usually inject all six skin sites then go back to where I started to place cannulas. An easy bilateral RFA is 10-12 minutes.

That's very impressive. Takes me much longer to do 6 needles.

 

[mdo1738]

That's very impressive. Takes me much longer to do 6 needles.

Are you placing the 2nd side while the 1st side burns? If not, easy way to save 90 seconds.

 

[Taus]

Are you placing the 2nd side while the 1st side burns? If not, easy way to save 90 seconds.

I debated if it’s worth the extra cost, 40-50 bucks/case. With how busy and booked out I’m getting… I think I’m going to make that change. It definitely shaves off several minutes to use six 18g rf needles for a bilateral vs three.

My most efficient sequence for a bilat lumbar rfa under local is this, if I don’t care about the cost of the 3 extra RF needles… open to suggestions to optimize.

-Numb right, numb left skin to bone w 25g quincke
- Place 18g rf needles right, numb mbb.
- Place rf needles left, numb left mbb
- test then burn right.
-test then burn left.

 

[Ronin1]

I decided I wanted to have less radiation exposure so I place all six for less lateral X-rays mainly plus HOPD so extra 40$ doesn’t matter too much

 

[Taus]

I decided I wanted to have less radiation exposure so I place all six for less lateral X-rays mainly plus HOPD so extra 40$ doesn’t matter too much

After putting that in writing…. The 40 bucks….. makes the decision seem all that more ridiculous. Placing all six starting now….

 

[Ferrismonk]

I'll take your suggestion and try not waiting for local as long. I agree its excessive as is, even though I used 18g tridents.

Here's my bilateral process.
1. Line up right side, mark 3 spots with skin marker, numb skin with 2%.
2. Insert 3 needles right side, motor test, inject 2% lido, wait 2 min, burn.
3. While waiting/burning right side, mark and numb left side.
4. When cannulas done on right, place on left, motor test, inject 2% lido, wait 2 min, burn
5. RN removes the needles.

My process takes about 20 min for a bilateral RFA.

 

[RoloTomassi]

I'll take your suggestion and try not waiting for local as long. I agree its excessive as is, even though I used 18g tridents.

Here's my bilateral process.
1. Line up right side, mark 3 spots with skin marker, numb skin with 2%.
2. Insert 3 needles right side, motor test, inject 2% lido, wait 2 min, burn.
3. While waiting/burning right side, mark and numb left side.
4. When cannulas done on right, place on left, motor test, inject 2% lido, wait 2 min, burn
5. RN removes the needles.

My process takes about 20 min for a bilateral RFA.

I do almost identical but without the 2 min. In some people waiting does make a difference but most are fine without.

 

[SSdoc33]

6 needles feels like a waste for an RF b/c you can only burn 1 side at a time. doesnt really speed things up.

6 needles for a MBB, 3 for RF

 

[BobBarker]

I would suggest using 1% for skin. It burns less.

I think this has been already suggested but I inject 2% and then motor test then burn. We fumble with the probes long enough for the right hand side that it is nearly perfectly set up.

The left side takes less time since I already have the probes out so I end up giving that side an extra 30 seconds to set up.

 

[callmeanesthesia]

I would suggest using 1% for skin. It burns less.

I think this has been already suggested but I inject 2% and then motor test then burn. We fumble with the probes long enough for the right hand side that it is nearly perfectly set up.

The left side takes less time since I already have the probes out so I end up giving that side an extra 30 seconds to set up.

I numb skin then hand the probe plugs to the MA/tech, then start to place the needles. Gives the skin local a few extra seconds to set up so they don’t jump with the initial pokes.

 

[Painologist]

Anyone else doing two 90 second burns per side with standard 18g needles? I feel it improves outcomes.

 

[clubdeac]

Anyone else doing two 90 second burns per side with standard 18g needles? I feel it improves outcomes.

I do

 

[mygalperin]

You must do both, sensory and motor, it does not take much of your time, but prevents damage to the big root

 

[mygalperin]

I put about 0.5-1 cc of 2% lido before I lesion. Are you all numbing before or after stim? Not sure it adds much more time but trying to cut down on anything that I can without jeopardizing safety.

Do not use 2%, it can cause a prolonged lower extremity weakness, 1% is adequate enough, mix it with kenalog also

 

[mygalperin]

I numb skin then hand the probe plugs to the MA/tech, then start to place the needles. Gives the skin local a few extra seconds to set up so they don’t jump with the initial pokes.

If you put needle quick enough through the tissues down to the bone, you do not need to numb the skin, you causing discomfort twice

 

[Ducttape]

Numb skin with 1%. 2% harder to find and more expensive. Don't need to wait but I do wait a sec and say "I'm testing - is this sharp?"

2% for the lesion. I will wait until the temp on the probe goes up a few degrees to ensure - in my mind only - that the local has diffused. Usually that's like 30-45 seconds. It also helps that patients think I am waiting for it to fully numb the lesion site.

I can only lesion 4 locations at a time so 6 needles is a waste of resources. And I've gone to only 1 2 min lesioning at 90 degrees and really haven't noticed difference in success.

 

[MitchLevi]

Skin with 1%, prior to testing drop 1-2% or bupi 0.25-0.5, motor test only and start the burn. The motor testing gives you plenty of time to get numb.

 

[BoardingDoc]

Everyone that drops local before motor testing... Doesn't that theoretically mean you can get a false negative motor test?

 

[BobBarker]

No. Not with the 30s to a minute it takes before testing. There isn’t enough time. Today I got a twitch at L5. I was too deep on a big person and couldn’t see the tip. The twitch was very, very noticeable. She had to hang out a little afterwards as her L5 nerve root was a little weak from the local after the rfa.

 

[callmeanesthesia]

If I have doubt on needle tip depth then I test then inject local. Mostly with bad scoli. More to avoid the numb leg issue than concern of masking nerve root stimulation.

 

[bedrock]

Do not use 2%, it can cause a prolonged lower extremity weakness, 1% is adequate enough, mix it with kenalog also

You must do both, sensory and motor, it does not take much of your time, but prevents damage to the big root

I’m concerned that in addition to your other posts, everything you just posted is wrong.

Sensory stim is useless and 1ml of 2% lidocaine does not cause motor block.

Between this and your other comments, I’m not sure you should be allowed to post on this forum until we have verified your training.

 

[buddababa]

Between this and your other comments, I’m not sure you should be allowed to post on this forum until we have verified your training.

agree

 

[mygalperin]

I’m concerned that in addition to your other posts, everything you just posted is wrong.

Sensory stim is useless and 1ml of 2% lidocaine does not cause motor block.

Between this and your other comments, I’m not sure you should be allowed to post on this forum until we have verified your training.

this is why it should be used, so no motor block will occur and pt can leave office w/o delay

 

[giddyup]

I learned to at least motor stim with rfa and certainly is standard of care as far as I'm concerned but I know of a few people including someone I work with who does not stim. burns off just positioning. Anyone seeing or doing this? Certainly cuts down on time but I'd imagine not worth the risk/liability.

I motor stim every time. Still get some surprises. Same as many above, test on one probe and move needle to needle. Only takes a minute. I localize after I test.

 

[giddyup]

Anyone else doing two 90 second burns per side with standard 18g needles? I feel it improves outcomes.

I do this. I took over for someone else who did 1 lesion with 20G and repeat RFA patients have stated mine have been more effective.

 

[Laryngospasm]

I put a cc of 2% on each medial branch before I motor test. Motor testing is for the lawyers. Gives me something to do while the 2% kicks in before I burn.

You will still get pos motor with 1cc on the MB after a minute or two. And I know a lot of people who don’t do motor but I’m not comfortable with that personally.

 

[BobBarker]

They aren’t placing the probes deep enough. I get motor twitches a lot at DRL5. Probably 10x a year

 

[hopefulgasman]

I get motor twitch quite often at DRL5 as well. Patients almost always say they feel it in their butt. This is desirable.

 

[MitchLevi]

I get substantial glute stim at L5 a fair amount of time; that probe is the most likely to make your pt jump or yell, even though the L2 and L3 MB probes commonly cause the most obvious muscle twitch. Those levels you’ll get the twitching that’s clearly visible and the pt won’t feel it half the time. I tend to be a little more steep at the L5 DPR than the other levels. Not saying perpendicular, just a bit steeper.

 

[clubdeac]

How are you guys getting L5 DPR twitch?! I don’t think I’ve ever been able to get twitch there in my 16 yr career

 

[Snowmen96]

How are you guys getting L5 DPR twitch?! I don’t think I’ve ever been able to get twitch there in my 16 yr career

To my knowledge, apart from anatomical variations, there is no multifidus innervated by the L5 MB. The normal response would be no twitch, with root stimulation being a sign that the nerve root itself is being stim'd, meaning the needle is too ventral.