Femoral Catheters....NOT IMPRESSED

[turnupthevapor]

I have been doing fem catheters for about two months for TKA. Even when I feel I place the catheter perfectly I am not thrilled with the results. I think I am going to stop doing them. Anyone feel they are worth the 15 minutes and aggravation to put in

I don't do sciatic cause we don't have a curvi-linear probe and my patients are way to fat to use our linear probe (also don't like fishing around with classical technique)

thanks

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[Planktonmd]

Most patient will get significant pain relief from a femoral nerve block.
Some patients (around 20%) will require a sciatic block as well.
If you are going to do only femoral blocks you should expect that around 20% of your patients (or alittle more) will not have satisfactory pain relief, and you need to have a multimodal approach to the pain management (NSAD's, IV PCA...)
You don't need ultrasound to do a sciatic block, you could do either an anterior sciatic block or a lateral popliteal block with nerve stimulator.
Both these blocks can be done in the supine position and are very effective.

I have been doing fem catheters for about two months for TKA. Even when I feel I place the catheter perfectly I am not thrilled with the results. I think I am going to stop doing them. Anyone feel they are worth the 15 minutes and aggravation to put in

I don't do sciatic cause we don't have a curvi-linear probe and my patients are way to fat to use our linear probe (also don't like fishing around with classical technique)

thanks

 

[SleepIsGood]

Most patient will get significant pain relief from a femoral nerve block.
Some patients (around 20%) will require a sciatic block as well.
If you are going to do only femoral blocks you should expect that around 20% of your patients (or alittle more) will not have satisfactory pain relief, and you need to have a multimodal approach to the pain management (NSAD's, IV PCA...)
You don't need ultrasound to do a sciatic block, you could do either an anterior sciatic block or a lateral popliteal block with nerve stimulator.
Both these blocks can be done in the supine position and are very effective.

Agree with plank's statements.

We typically do the sciatic block (infraglut, parabiceps approach) first with pt prone. Flip them over and drop th Fem Nerve cath. i agree, to get GOOD results you must do both of them.

As plank said, you can do both supine. The only thing is you need ultrasound to do the anterior approach to the sciatic. Also since you are going through MANY muscle layers, it may be painful. So...

 

[amyl]

really?!? I feel like we have great results with them. seems like the back of the knee pain is less than 20% actually -- we don't have to top that many off w sciatic -- a little prn narcs seem to do the trick -- if they do happen to complain. seems like less than 10% c/o sciatic distribution pain.
are you using ultrasound or stim or both? we use both most of the time -- occasionally skip the u/s 'cause all the machines are taken).
in PP i guess the catheters are likely not worth the trouble/lack of reimbursement for follow up but i would want one if i had a knee done.
what solution are you running?
do you bolus the catheters in the pacu? sometimes you need to catch up...

 

[sevoflurane]

Some simple questions to ask if you are not satisfied with your fem cath's:

What is your min. ma? Are you truly getting a patellar snap and nothing else? Do you hook your stimulator back up and check for twitches once you place and secure your catheter? What are you using for LA/cocktail? What is your infusion rate/PC bolus set at? A good number of people may complain of posterior pain if you leave out the sciatic. You can use your USD probe to determine where the sciatic divides and make sure you get it before it divides in the pop fossa - otherwise you may be fooled into thinking you have the sciatic when indeed you only have one of it's branches (CP/T nerve..benefit of USD). Or... do a high anterior approach... single shot. Either way nearly 100% pain free in pacu and + extra 7 units.

Another thing to keep in mind... Some people will never be happy.

 

[sevoflurane]

Agree with plank's statements.

We typically do the sciatic block (infraglut, parabiceps approach) first with pt prone. Flip them over and drop th Fem Nerve cath. i agree, to get GOOD results you must do both of them.

As plank said, you can do both supine. The only thing is you need ultrasound to do the anterior approach to the sciatic. Also since you are going through MANY muscle layers, it may be painful. So...

No you don't. I think it takes more time to do this block with USD. Only block I think is easier to do with landmarks. Feel for femur... walk off.. bang. My 2 cents.

 

[periopdoc]

Either way nearly 100% pain free in pacu and + extra 7 units.

Apparently not for very much longer, if you are doing them routinely. It looks like we are going to have to start doing them in the post-op area "for pain refractory to routine measures" in order to get the additional units. So much for providing optimal care.

- pod

 

[dA pilot]

Are people doing popliteal sciatic blocks for TKAs? Can it be adequate coverage for the knee? I do a good amount of these for foot and ankle surgery and if the surgeon works past about the mid calf the patient will feel it. My current practice is a femoral nerve catheter and a subgluteal sciatic block for posterior pain post op if the patient needs it.

 

[sevoflurane]

Are people doing popliteal sciatic blocks for TKAs? Can it be adequate coverage for the knee? I do a good amount of these for foot and ankle surgery and if the surgeon works past about the mid calf the patient will feel it. My current practice is a femoral nerve catheter and a subgluteal sciatic block for posterior pain post op if the patient needs it.

I do fem + ant. sciatic routinely for TKA's. Sometimes I'll do a "high" popliteal block. I actually extend my definition of the popliteal block. Place the USD in the pop fossa, find both nerves and trace them back until they become the sciatic. Then, block the sciatic about 3-5 inches above this point. It is still lower than where you would block the sciatic via the infragluteal approach. This apporach has been very reliable in my experience.

 

[sevoflurane]

The reason I do a "high" Pop block is that it has the advantage of sparing muscle groups of the mid-upper thigh. I feel this helps out if you are walking POD #0.

 

[Frank Rizzo]

I also do the 'high pop block' approach. Seems to work well. No u/s, just nerve stim and a marker. I draw out the usual landmarks, instead of 7 cm up, i go 15 cm. Then I take a 80 or 100 cm stim needle and go straight down. Usually get good stim on first pass. Fine tune down to >0.3, then inject 30 ml 0.5% naropin. Whole process, including flipping the patient, takes about 10 minutes.

 

[narcusprince]

really?!? I feel like we have great results with them. seems like the back of the knee pain is less than 20% actually -- we don't have to top that many off w sciatic -- a little prn narcs seem to do the trick -- if they do happen to complain. seems like less than 10% c/o sciatic distribution pain.
are you using ultrasound or stim or both? we use both most of the time -- occasionally skip the u/s 'cause all the machines are taken).
in PP i guess the catheters are likely not worth the trouble/lack of reimbursement for follow up but i would want one if i had a knee done.
what solution are you running?
do you bolus the catheters in the pacu? sometimes you need to catch up...

Good friend,
I am not impressed with Femoral nerve catheters too. They are definetly not worth the trouble. Whats the average time to discharge for your knees in PP? I also feel if you have to give a patient PRN narcs for knee pain which invariably 75-80% get postop than why do you need a catheter. Single shot to me would be the best approach as your not infusing, you do not have to round on the patients, and you decrease your incidence of catheter related complications. Plus their is soo much variability with the way that the catheters are inserted, U/s with stim, Stim, U/s with catheter guided stim. Without much evidence that one is superior to the other. Also, at our place of workship we do a ton of redo knees many of these patients have chronic pain issues and are not opiate naive so your giving them tons of narcotics anyway. Not worth the hassle single shot and call me if you cannot get the narcs under control.

 

[bostonblaz]

i actually somewhat agree that it is a pain in the butt to do some days and would actually stop putting them in and stuck to just single shots but the patients and the physical therapists are very much into them and have seen great results. From the patient end it is always the people who had there knee done 5 yrs plus ago that are having the other one done now that say this time was vastly improved. The pt people in our hospital have been the biggest supports. They feel that difference is night and day. The rom and level of participation they get is so much improved. For those reasons alone I will continue to do them, and also will replace the ones my older partners that are not so slick put in.blaz

 

[maceo]

i had a orthopod tell me just last week he hates fem blocks. patients cant get out of bed the next day. he wants them out of bed and he saw a few incidences of fem nerve palsy

 

[SleepIsGood]

i had a orthopod tell me just last week he hates fem blocks. patients cant get out of bed the next day. he wants them out of bed and he saw a few incidences of fem nerve palsy

I feel like orthopods want to blame ANY neuro deficit on something related to anesthesia. Thats the tough part.

But seriously, during a total knee...if you see how much pushing, pulling, and aggressiveness is put into fixing that knee, it's surprising that MORE neuro deficits directly related to the orthopods manipulation doesnt occur. I'm surprised there's not more 'stretch' injuries from nerves.

 

[Narcotized]

A good femoral block, single shot or catheter, is an excellent pain control technique for all knee surgeries. Catheters in general are just one huge pain in the ass compared to the speed and ease of single shots. It just depends if that extra day or 2 of pain relief is worth it. I do my sciatics in the GT/IT groove around the butt crease and it's usually located very fast and gives you that extra posterior kneee relief.

I don't use ultrasound on the Femorals. It's faster for me to do it without. If you get Sartorius twitching, go a little deeper and possibly lateral. Ultrasound easily locates that bird's beak lateral to the Femoral Artery which is Sartorius, but finding the posterior branch (the one you want) is a little more difficult to find with ultrasound. After some practice it's so fast to hit this without ultrasound that I don't see the benefit using it.

I don't use ultrasound on Sciatics as they tend to be deeper and not easily seen, and the GT/IT location is pretty reliable. I use ultrasound on all upper extremity blocks. It guarantees one stick in the neck everytime and avoids the complications of pneumo, vessel puncture, etc. I also use it on posterior popliteals because of its ease of location, and on whales for Femorals that don't have a palpable pulse.

 

[Shadowfax8]

Our group mostly does TKAs under Spinal. Before the injection, we place the catheter for continuous femoral nerve block, and then sit them up and perform the spinal and include Duramorph in the spinal injection. Both patients and PACU nurses (your harshest critics) are very satisfied. And since I used Duramorph in the spinal I only order 50 mcg of Fentanyl max in the PACU (because I want the nurse to call me if the pt needs more to ascertain how my block went). The ortho docs tell me they rarely get calls at night for breakthrough pain using this method. I've been in private practice now for about 19 months and can perform a cont FNB in about 5 min. It's worth 12 units, plus 3 more for the DURAmorph, plus 7 units for the TKA, and at least 4 for time = 26 units for a little more than 1 hour's work. And the patients seem very satisfied. I feel the 20% statistic mentioned in previous posts is rather high.
PS: we use 0.2% Ropivicaine in our cFNB, starting bolus 10 ml while they're putting the dressing on at the end and then set the drip at 8ml/hr and titrate up prn to max of 14 ml/hr.

 

[hokie]

I've always been a little confused about this... When we do a block for post-op pain we get a flat fee (negotiated with insurer). When you say that you get 7 units (or whatever) are you billing for that differently? Or is it just that the fee you get is apprx. equal to 7 units?
I am admittedly not a billing expert and will talk to my group for more info. too.

 

[turnupthevapor]

one of the conferences I attended talked about a double crush injury...putting a block in and putting a tourniquet over the block may increase the risk of nerve injury?

That is always my concern when I think about doing popliteal for the sciatic portion of the TKA. Anyone validate this?

 

[SleepIsGood]

Just a suggestion.

this is a great thread..however, keep in mind insurance companies and others may be monitoring this site. Perhaps discussions on the efficacy of this post op pain modality is better reserved amongst ONLY anesthesiologists in the PRIVATE Forum.

 

[turnupthevapor]

I also do the 'high pop block' approach. Seems to work well. No u/s, just nerve stim and a marker. I draw out the usual landmarks, instead of 7 cm up, i go 15 cm. Then I take a 80 or 100 cm stim needle and go straight down. Usually get good stim on first pass. Fine tune down to >0.3, then inject 30 ml 0.5% naropin. Whole process, including flipping the patient, takes about 10 minutes.

one of the conferences I attended talked about a double crush injury...putting a block in and putting a tourniquet over the block may increase the risk of nerve injury?

That is always my concern when I think about doing popliteal for the sciatic portion of the TKA. Anyone validate this?