Nerve blocks

[24858]

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Does anyone here do peripheral nerve blocks if the INR is elevated. I have done them and from what I remember there is no issue with doing them, I tried to find literature to back up my belief but couldnt find any..
Does any have an INR at which they would consider a cutoff?

As a side question...say if you were called to do a nerve block from the ER in a patient with bony mets to the tibia and the patient is in excruciating pain...and there are no pain docs in your hospital...would you do a popliteal block for the patient...if you do regional in the OR for acute pain..is there any limitation to you doing a nerve block for a chronic pain patient..just a one time block..and instruct them to find an interventional pain doc for their issue?

 

[jetproppilot]

Does anyone here do peripheral nerve blocks if the INR is elevated. I have done them and from what I remember there is no issue with doing them, I tried to find literature to back up my belief but couldnt find any..
Does any have an INR at which they would consider a cutoff?
As a side question...say if you were called to do a nerve block from the ER in a patient with bony mets to the tibia and the patient is in excruciating pain...and there are no pain docs in your hospital...would you do a popliteal block for the patient...if you do regional in the OR for acute pain..is there any limitation to you doing a nerve block for a chronic pain patient..just a one time block..and instruct them to find an interventional pain doc for their issue?

I'm a regional advocate.

I'm also (probably too much) cautious when it comes to regional nerve blocks and coagulation issues.

That being said, I won't do regional nerve blocks unless the INR is normal.

Usually.

 

[24858]

I guess what I am trying to say is would you feel comfortable doing a nerve block for a chronic pain patient to give them some pain relief?
I know u r new to u/s guided nerve blocks...maybe you will change your practice?

I'm a regional advocate.

I'm also (probably too much) cautious when it comes to regional nerve blocks and coagulation issues.

That being said, I won't do regional nerve blocks unless the INR is normal.

Whatever normal means to you is what's important.

Set a standard.

The rest of your post is kinda all over the place so

Couldja consolidate it into a cuppla questions?

 

[epidural man]

Does anyone here do peripheral nerve blocks if the INR is elevated. I have done them and from what I remember there is no issue with doing them, I tried to find literature to back up my belief but couldnt find any..
Does any have an INR at which they would consider a cutoff?

As a side question...say if you were called to do a nerve block from the ER in a patient with bony mets to the tibia and the patient is in excruciating pain...and there are no pain docs in your hospital...would you do a popliteal block for the patient...if you do regional in the OR for acute pain..is there any limitation to you doing a nerve block for a chronic pain patient..just a one time block..and instruct them to find an interventional pain doc for their issue?

The ER would never call for a nerve block.

Nerve blocks last 3-24 hrs (depending on a few things). Where does that get you in a chronic pain patient?

Also, for your INR question. Probably 90% of the hospitals in the US don't offer nerve blocks to patients (that statistic is completely made up....but it may be close). What that means is nerve blocks are like an amazing fruit that only people that live in Puerto Rico get to enjoy (and I'm talking about Canepas...) The rest of the world get along just fine without it, but those who get to eat Canepas wonder how the rest could live without it.

In other words, regional is great for lots of things, but almost never imperative. SOOO, why take the risk? One could argue that you aren't going to hurt the patient, and that is probably way true...but....again, it's a dessert of an anesthetic. Of course there are cases where it is almost imperative, but those are case by case.

 

[B-Bone]

I guess what I am trying to say is would you feel comfortable doing a nerve block for a chronic pain patient to give them some pain relief?
I know u r new to u/s guided nerve blocks...maybe you will change your practice?

The question regarding nerve block for chronic pain pts is, what's the end point? they might feel better for 12-18 hours, but what about after that? are you gonna keep doing blocks? it's just not a practical solution. For these chronic (esp cancer) pain pts, they are gonna need systemic pain meds (multimodal, narcs, neuromodulators, NSAIDS, maybe steroids, ? bisphosphonates) and depending on the situation, maybe some interventional procedure (pump/stim/ablation/etc). The treatment plan is not going to be in place by the time your block wears off.

Regarding coag status and PNBs, ASRA dropped some heavy (though not particularly evidence based) recs last year basically saying that we should treat PNBs like neuraxials, at least from a coag perspective ("for deep plexus and peripheral nerve blocks we recommend that recommendations regarding neuraxial techniques be similarly applied"). US technology was not addressed. In this respect, you can look at the ASRA anticoagulant guidelines. They have a wealth of info about what is kosher regarding how long after plavix/heparin/lovenox/blahblahblah you should wait to do a neuraxial procedure (and by extension, a peripheral nerve block), but notably absent is an INR cutoff-it just says "normalized- and a platelet cutoff. THese you just ahve to decide for yourself. Alos, they don't provide any real guidance on newer agents like Pradaxa (basically says "better be careful!").

Regional Anesthesia & Pain Medicine:
January/February 2010 - Volume 35 - Issue 1 - pp 64-101
doi: 10.1097/AAP.0b013e3181c15c70
Asra Practice Advisory
Regional Anesthesia in the Patient Receiving Antithrombotic or Thrombolytic Therapy: American Society of Regional Anesthesia and Pain Medicine Evidence-Based Guidelines (Third Edition)
Horlocker, Terese T. MD*; Wedel, Denise J. MD*; Rowlingson, John C. MD†; Enneking, F. Kayser MD‡; Kopp, Sandra L. MD*; Benzon, Honorio T. MD§; Brown, David L. MD∥; Heit, John A. MD*; Mulroy, Michael F. MD¶; Rosenquist, Richard W. MD#; Tryba, Michael MD**; Yuan, Chun-Su MD, PhD††

I personally don't feel the risk of doing, say, a SS fem block in somebody with an INR of 1.3 or a popliteal in someone with platelets of 90,000 is crazy, but it totally depends on the situation. I think the ASRA guidelines are going to get more strict regarding PNBs. Just my intuition. Anyway, hope that's helpful.

 

[Idiopathic]

i usually avoid infraclavicular completely and supraclavicular 9 times out of 10 in cases where anticoagulation is an issue. but as with anything it depends on the context. i would do US guided blocks on any other part of the body, if i thought the situation called for it.

i would caution against treating chronic pain patients with peripheral regional techniques. it will be a wholly unsatisfying experience for you. also, a popliteal block for tibial pain would probably not be a great choice, if I were going to do something for the pain, Id probably consider a classic sciatic + femoral with catheters that they could keep for a few days, assuming this is palliative. i think you would be underwhelmed at the quality of pain relief, however. its not completely unreasonable to try, though, if it can keep the patient out of the hospital until they can get more definitive consultation.

 

[deleted185747]

For the tibia pain from mets I would recommend a single dose of radiation ~8gy to the tibia. Your patient would have an 80% chance of some pain relief and 50% of complete pain relief.

ARTICLES Journal of the National Cancer Institute, Vol. 97, No. 11, June 1, 2005
Randomized Trial of Short- Versus Long-Course

Radiotherapy for Palliation of Painful Bone Metastases

William F. Hartsell , Charles B. Scott , Deborah Watkins Bruner , Charles W.

Scarantino , Robert A. Ivker , Mack Roach, III , John H. Suh , William F. Demas ,

Benjamin Movsas , Ivy A. Petersen , Andre A. Konski , Charles S. Cleeland ,

Nora A. Janjan , Michelle DeSilvio

Background:


Radiation therapy is effective in palliating pain

from bone metastases. We investigated whether 8 Gy delivered

in a single treatment fraction provides pain and narcotic

relief that is equivalent to that of the standard treatment

course of 30 Gy delivered in 10 treatment fractions over 2

weeks.

Methods: A prospective, phase III randomized study

of palliative radiation therapy was conducted for patients

with breast or prostate cancer who had one to three sites of

painful bone metastases and moderate to severe pain. Patients

were randomly assigned to 8 Gy in one treatment fraction

(8-Gy arm) or to 30 Gy in 10 treatment fractions (30-Gy

arm). Pain relief at 3 months after randomization was evaluated

with the Brief Pain Inventory. The Wilcoxon – Mann –

Whitney test was used to compare response to treatment in

terms of pain and narcotic relief between the two arms and

for each strati

fi cation variable. All statistical comparisons

were two-sided.

Results: There were 455 patients in the 8-Gy

arm and 443 in the 30-Gy arm; pretreatment characteristics

were equally balanced between arms. Grade 2 – 4 acute toxicity

was more frequent in the 30-Gy arm (17%) than in the

8-Gy arm (10%) (difference = 7%, 95% CI = 3% to 12%;

P


= .002). Late toxicity was rare (4%) in both arms. The overall

response rate was 66%. Complete and partial response

rates were 15% and 50%, respectively, in the 8-Gy arm compared

with 18% and 48% in the 30-Gy arm (

P = .6). At 3

months, 33% of all patients no longer required narcotic medications.

The incidence of subsequent pathologic fracture was

5% for the 8-Gy arm and 4% for the 30-Gy arm. The retreatment

rate was statistically signi

fi cantly higher in the 8-Gy

arm (18%) than in the 30-Gy arm (9%) (

P <.001). Conclusions:

Both regimens were equivalent in terms of pain and narcotic

relief at 3 months and were well tolerated with few adverse

effects. The 8-Gy arm had a higher rate of re-treatment but

had less acute toxicity than the 30-Gy arm. [J Natl Cancer

Inst 2005;97:798 – 804]

 

[pgg]

For the tibia pain from mets I would recommend a single dose of radiation ~8gy to the tibia. Your patient would have an 80% chance of some pain relief and 50% of complete pain relief.

That's neat, but not really an option for an anesthesiologist called to the ER to help out with acute pain control.



Of the blocks I've done for surgery in chronic pain patients, my nonscientific anecdotal personal trend leans toward a big fat 'meh' when it comes to their postop pain control. I've been underwhelmed by the results. If the ER called me for a patient like that I'd go with IV narcotics, a prescription for some PO narcotics, and a referral to someone who could take care of their pain on an ongoing basis.

"Intractable pain" in the ER usually translates to "intractable pain after 2 whole mg of Dilaudid" ... for some reason their institutional cowboy-ness doesn't extend to pain meds.


My INR cutoff for a purely elective peripheral nerve block is the same as for neuraxial - 1.4. ASRA didn't help with their latest guidelines. Now I'd only do a block when the INR >1.4 if there was a compelling reason to go regional over GA, and I'd document the hell out of that reason and periodic post-procedure exams.

 

[Oggg]

+1
you'd need femoral/sciatic blocks. Tell them you wish you could help but you can't.
Use the INR as an excuse. I've been asked to put in an epidural for cancer pain , but that's just not a sustainable therapy, so I don't even start it.

In the OR I'd considering doing the more peripheral nerve blocks with ultrasound in patient with elevated INR (2.0?). But probably not sciatic since the visibility with utlrasound is so poor, and the infragluteal artery runs close to the sciatic high up in the pelvis.

 

[Hamhock]

But probably not sciatic since the visibility with utlrasound is so poor, and the infragluteal artery runs close to the sciatic high up in the pelvis.

Is there an indication for sciatic block at any other site than just above the pop fossa/at the bifurcation?

Is there any reason to go more proximal?

HH

 

[epidural man]

Is there an indication for sciatic block at any other site than just above the pop fossa/at the bifurcation?

Is there any reason to go more proximal?

HH

Lots

 

[Hamhock]

Lots

Please educate...of "lots", please list two or three?

I guess I could go look it up, but that is one of the benefits of SDN: unexpected education.

HH

 

[pgg]

Is there an indication for sciatic block at any other site than just above the pop fossa/at the bifurcation?

Is there any reason to go more proximal?

Better coverage of the knee, posterior thigh coverage for tourniquet pain are the big ones.

 

[epidural man]

Better coverage of the knee, posterior thigh coverage for tourniquet pain are the big ones.

👍

I'm sure there are others as well (like amputees), but those were the ones I was thinking.

 

[pgg]

👍

I'm sure there are others as well (like amputees), but those were the ones I was thinking.

You ever try to pick out the tibial vs common peroneal for your popliteal blocks? Ie, if your intent is analgesia for a particular area of the foot.

The reason I ask - I did an easy nerve stim popliteal a couple days ago for an ORIF revision (mainly to avoid GA in an old/sick person). Stuck her my usual 7 cm above the popliteal crease, got a good plantar flexion twitch. Incision was dorsal/lateral foot, up toward the ankle (superficial peroneal territory). She needed a bit of local from the surgeon around the incision. Deep structures were numb, she was awake and felt nothing the rest of surgery. No additives, only got about 15 hours out of the block. The block was placed a good 45 minutes prior to incision, so I don't think my choice of 0.5% ropivacaine and a slow setup was the problem. It just seemed to miss a branch of the common peroneal that I wanted.

Popliteals are super easy reliable blocks but I wonder if there's any utility in chasing a foot twitch in a particular direction.

 

[epidural man]

You ever try to pick out the tibial vs common peroneal for your popliteal blocks? Ie, if your intent is analgesia for a particular area of the foot.



Popliteals are super easy reliable blocks but I wonder if there's any utility in chasing a foot twitch in a particular direction.

I don't, I always try to find the point where the two branches come together. I think finding the side (twitch) that corresponds best with surgical site has been described. It's probably not a bad idea if using nerve stim.

 

[Oggg]

1. Netter shows an articular branch to the knee coming off the sciatic at mid-upper thigh level.
2. Popliteal sciatic blk is one of the slowest blocks to setup
3. That said, there is a study that shows onset is faster if you use ultrasound to block the tibial and peroneal nerves separately, below the bifurcation.

 

[sevoflurane]

Yet another advantage of USDGRA. Particularly when doing a popliteal. If you get a tibial twitch and decide to go with it... how do you know the peroneal component is going to be blocked? You could be below the bifurcation right? I've seen the bifurcation above the magical 7cm line under USD plenty of times. This is one reason popliteals need more volume. Just makes me happy to trace back the tibial and peroneal and see them come together... then I go an inch above that and deposit LA.

The best twitch is when you get components of both nerves at the same time. Plantar flexion/evertion and dorsiflexion/invertion simultaneously just makes me happy. 😀

 

[sevoflurane]

Another option is to go lateral approach and pick up the sciatic mid thigh (esay positioning/supine). You are high enough that you will get the sciatic before it bifurcates.

I go about 3-6 inches higher than the picture above. "High Popliteal" for those TKA's where you want to get the posterior knee. This will usually pick off the branch that Oggg mentioned in 95% of patients + patients retain much of their muscular function in the thigh.

 

[sevoflurane]

+ patients retain much of their muscular function in the thigh.

= won't have hamstrigs out for walking on POD "0"

 

[Gasworks]

When I was in training the guy who ran the pain service was called to do an axillary block on a hospital employee with slightly elevated INR (1.7 i think). Unfortunately for the doc, we'll call him Bob, went against his hard limit of 1.5 and did the block anyway. For his troubles he got to enjoy an entire month of being followed around by a less than sane person with a bruise covering most of his upper arm shouting "HEY BOB.. THANKS FOR THE HEMATOMA".

In reference to your specific example of pt with bony mets and acute "excruciating" pain in the ER, the answer here is IV pain meds and admit for palliative care / pain control. Before you repel down the side of the building and try to impress the sexy ER nurses with your powers of pain management take a moment to consider that this patient is most likely hypovolemic, already has massive pain meds on board and a near zero albumin. They may also have other issues and meds that are causing platelet dysfunction. The last thing this poor patient needs is local anesthetic toxicity or an emergent evacuation of hematoma with whatever blood loss comes with it. The vascular surgeons will laugh at you for months if you have to call them in for something like this!

 

[Ketafol20]

I find it difficult to have a hard and fast rule for just about anything in medicine. So, if I am asked to place a block in someone with an elevated INR then I assess the situation. If the benefits outweigh the risks then I will perform it. This is why we are doctors and not nurses. We use our education and clinical judgement to make the difficult decisions.

For example, let's say you have a pt with an INR of 1.3 or even 1.4. He has a fracture of the arm or lower leg. He recently ended up in the unit after having hernia surgery because he has severe pulmonary htn to the tune of 90/10 with RV strain on ECG. The fracture needs to be repaired and it can easily be done under regional block. Btw, he has recent cardiac stents so it's not wise to reverse his INR. You can perform a regional block in an area that would not cause nerve injury if a hematoma were to occur ie: axillary or popliteal. Why would you put this guy to sleep? Sure you could reverse the INR and bridge with heparin or even lovenox but is this really necessary? We all have different ways to handle this but I wouldn't say that regional is wrong by any means.

As far as blocks in the ER for chronic pain pts go, well there had better be a damned good reason for it. In general, blocks for chronic pain pts are a losing proposition. The blocks rarely work completely because the pain is centralized and the block will wear off and then what? Your back at square one.