Too many wet-taps

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Couple of things.

Don't worry about a lumbar wet tap. A headache isn't the worst thing in the world and it rarely is dangerous.

Second thing - use better control.

Thirdly, think about the anatomy a little bit. I suggest moving up a level from where you think you are at. Look at this MRI T1 Sagital (fat is bright) I pulled off the internet - but this is very typically of everyone. The bright signal next to the arrow is the epidural fat. The black lines on each side are the ligament (posterior) and the dura (anterior). The epidural space at L5/S1 is very thin, and in most, not even visible on MRI. The epidural space increases as you move up and is often the widest at L3/4, maybe L2/3. However, notice that the space in a single level varies dramatically to almost non-existent to very wide (3-5mm). The widest epidural space is in the middle of the space (in a caudal-cephelad direction), so try and do your best to be in the middle of the space.

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epidural man said:
Couple of things.

Don't worry about a lumbar wet tap. A headache isn't the worst thing in the world and it rarely is dangerous.

Second thing - use better control.

Thirdly, think about the anatomy a little bit. I suggest moving up a level from where you think you are at. Look at this MRI T1 Sagital (fat is bright) I pulled off the internet - but this is very typically of everyone. The bright signal next to the arrow is the epidural fat. The black lines on each side are the ligament (posterior) and the dura (anterior). The epidural space at L5/S1 is very thin, and in most, not even visible on MRI. The epidural space increases as you move up and is often the widest at L3/4, maybe L2/3. However, notice that the space in a single level varies dramatically to almost non-existent to very wide (3-5mm). The widest epidural space is in the middle of the space (in a caudal-cephelad direction), so try and do your best to be in the middle of the space.

View attachment 244287
Click to expand...

Name checks out....
 
epidural man said:
Couple of things.

Don't worry about a lumbar wet tap. A headache isn't the worst thing in the world and it rarely is dangerous.

Second thing - use better control.

Thirdly, think about the anatomy a little bit. I suggest moving up a level from where you think you are at. Look at this MRI T1 Sagital (fat is bright) I pulled off the internet - but this is very typically of everyone. The bright signal next to the arrow is the epidural fat. The black lines on each side are the ligament (posterior) and the dura (anterior). The epidural space at L5/S1 is very thin, and in most, not even visible on MRI. The epidural space increases as you move up and is often the widest at L3/4, maybe L2/3. However, notice that the space in a single level varies dramatically to almost non-existent to very wide (3-5mm). The widest epidural space is in the middle of the space (in a caudal-cephelad direction), so try and do your best to be in the middle of the space.

View attachment 244287
Click to expand...

That is an MRI rarely encountered in the pain clinic, but often seen on the OB wards. Good advice
 
acidbase1 said:
This was my first thought. Use it to help find midline and level as well
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I couldn’t disagree more. The OP needs lots and lots of reps doing this procedure in the standard way until he/she develops a system and it clicks. In the community practice where most of you are headed, there is no time to grab an ultrasound from another floor, bring it to OB, etc. If you did this at my group, you would be a huge outlier. Your partner would have been called and come up, assessed, and placed epidural by the time you had the ultrasound ready to go. You need to be on/off the labor floor in 30 min or less 95% of the time in my practice (and many others like ours).

Sorry if you guys don’t want to hear it, but this is the real world perspective.
 
I would advise a new person who's getting a lot of wet taps to NOT use (only) air in a syringe. A tiny pneumocephalus results in a very large headache and odd neuro symptoms that will freak everyone right the hell out.

A small air bubble in a syringe with saline gives great tactile feedback. Wait until you're proficient before trying all-air.
 
acidbase1 said:
This was my first thought. Use it to help find midline and level as well
Click to expand...

If you are getting wet taps while advancing 1mm at a time there is one problem- you are not recognizing the epidural space when you are in it. Rarely you might have a clotted off Tuohy, but your problem is probably that you just are tap tap tapping your LOR syringe too softly. When you push harder you probably get a lot of false losses 2 or 3 cm deep so you’ve learned to barely push. You can improve those problems by 1) not checking loss of resistance until you are deeper and 2) using saline so that you can push harder without leaking air. Plus with saline you have the added bonus of getting your resistance back if you do get a false loss because you are would inject saline into that false space.

In addition, you should be able to appreciate the feel of the needle passing through ligament so that your loss of resistance is more confirmation that you are in the epidural space rather than a surprise. I can see it when a resident engages the ligament while I’m standing a few feet away so it’s hard to imagine you can’t appreciate the feel of ligament if you are paying attention to the feel of the needle as you advance it and not just focusing completely on tapping the syringe between advances.

Also, 1mm is overly cautious. Don’t advance it 1cm at a time or anything but 1mm isn’t enough unless you are already in ligament. I do continuous pressure, but I think advancing 2-3mm at a time is good while you are learning.
 
okayplayer said:
there is no time to grab an ultrasound from another floor, bring it to OB, etc.
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Pretty sure there's an ultrasound machine already on every single L&D unit in the country.

U/S for neuraxial is a valuable skill to have, but it's not something you should need any more than 1% of the time max. I can see it being a good tool for teaching a brand spanking new resident though.
 
Although I use continuous technique, I'd advise the OP to at least continue to use intermittent until you're needle is engaged in flavum. You need to fully appreciate what the flavum feels like bc there is nothing else in the world that gives you that tactile feedback with your tuohy needle. Also, this will help you appreciate the tactile feedback you get in the tissue before entering flavum. Once you're in flavum and know you are, you can use continuous to get that great LOR.
 
okayplayer said:
I couldn’t disagree more. The OP needs lots and lots of reps doing this procedure in the standard way until he/she develops a system and it clicks. In the community practice where most of you are headed, there is no time to grab an ultrasound from another floor, bring it to OB, etc. If you did this at my group, you would be a huge outlier. Your partner would have been called and come up, assessed, and placed epidural by the time you had the ultrasound ready to go. You need to be on/off the labor floor in 30 min or less 95% of the time in my practice (and many others like ours).

Sorry if you guys don’t want to hear it, but this is the real world perspective.
Click to expand...

I’m not saying use it for life, but as a tool to learn until her gets comfortable. US removes some variables and could help get him started. He’s also not in charge of a busy OB practice. Later likely not practical
 
acidbase1 said:
I’m not saying use it for life, but as a tool to learn until her gets comfortable. US removes some variables and could help get him started. He’s also not in charge of a busy OB practice. Later likely not practical
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If he had problems US would solve he wouldn’t be getting wet taps, he’d be hitting bone.
 
I have yet to use ultrasound for epidurals during residency, do you guys think it’s a skill I should go out my way to learn? As others have said, it does take more time and effort.
 
dipriMAN said:
I have yet to use ultrasound for epidurals during residency, do you guys think it’s a skill I should go out my way to learn? As others have said, it does take more time and effort.
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It's a skill that I know that they teach in OB anesthesia fellowships so it couldn't hurt to at least try it . You don't have to actually perform it using U/S, just get an appreciation for the anatomy so you know what you're looking at.
 
dipriMAN said:
I have yet to use ultrasound for epidurals during residency, do you guys think it’s a skill I should go out my way to learn? As others have said, it does take more time and effort.
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don't do it

I bet the odds of U/S speeding the placement of an epidural for an experienced person are less than 1 in 1000.
 
Mman said:
don't do it

I bet the odds of U/S speeding the placement of an epidural for an experienced person are less than 1 in 1000.
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Of course it doesn’t speed the process. But on that one or two patients per year when you run into a wall of bone it can be an asset.
 
SaltyDog said:
Of course it doesn’t speed the process. But on that one or two patients per year when you run into a wall of bone it can be an asset.
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I guess I don't have that problem. Labor epidurals are easy. The ones that aren't easy are the ones ultrasound is least useful on.
 
Mman said:
The ones that aren't easy are the ones ultrasound is least useful on.
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Why do you say that? Example? To me an example where U/S comes in handy would be the BMI 40 with some scoli that you can’t appreciate because it’s buried under 3” of fat. You can’t feel anything, and what is midline on the surface is actually 2” off from where the spine is.

And yes, I agree that 99% of labor epidurals are easy. If you say 100% are easy you’re full of sheet.
 
I'm just hoping op is safe and wasnt slowly advancing himself towards the edge of the cliff like he does his epidurals....that may not end well for the young man.
 
SaltyDog said:
Why do you say that? Example? To me an example where U/S comes in handy would be the BMI 40 with some scoli that you can’t appreciate because it’s buried under 3” of fat. You can’t feel anything, and what is midline on the surface is actually 2” off from where the spine is.

And yes, I agree that 99% of labor epidurals are easy. If you say 100% are easy you’re full of sheet.
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people with scoliosis I can almost always just have them tell me if I'm off to the left or right and then just walk it in.
 
placed an epidural on a lady that had scoliosis s/p Harrington rods, used the US to map out where the rods were and where the epidural space was.. it can be very helpful in the rare occasion
 
nolagas said:
If he had problems US would solve he wouldn’t be getting wet taps, he’d be hitting bone.
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It could help tell him the depth of flavum. But whatever you’re right I’m wrong.
 
fittipaldi1of1 said:
placed an epidural on a lady that had scoliosis s/p Harrington rods, used the US to map out where the rods were and where the epidural space was.. it can be very helpful in the rare occasion
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That’s great but be careful, some surgeons leave no epidural space at the lumbar level even for scoliosis repair, and for standard lumbar fusions almost definitely no remaining epidural space.
 
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caligas said:
That’s great but be careful, some surgeons leave no epidural space at the lumbar level even for scoliosis repair, and for fusions almost definitely no remaining epidural space.
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Ran into exactly this for what appeared to be a near total scoliosis repair on our OB floor a couple of months ago. Thankfully the patient presented for section - had no trouble getting into the intrathecal space (right through the scar), but previous attempts for epidurals on her have all been wet taps...
 
fittipaldi1of1 said:
placed an epidural on a lady that had scoliosis s/p Harrington rods, used the US to map out where the rods were and where the epidural space was.. it can be very helpful in the rare occasion
Click to expand...
I personally think an epidural attempt is contraindicated in this situation if you can’t go belownor above the surgery site. What do others think?
 
dipriMAN said:
I personally think an epidural attempt is contraindicated in this situation if you can’t go belownor above the surgery site. What do others think?
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Agree if it was a lami/fusion. Scoli repairs often leave the epidural space in tact. Full length scoli repairs also make placement challenging since they are fused in lordosis and hardware can be in the way on a paramedian approach.
 
I think it depends on comfort level and the patients history. Above or Below always better.
I recently did a complicated lumbar drain that needed some fluoro to help out with placement.

If you have a chronic pain Sickle Cell patient with full blown and frequent sickle crisis, it might be worth a try. (Likely omit fluoro and go for USD for placement).

If you wet tap her, just place a catheter and run it as spinal cath analgesia. Risks vs Benefit decision.
 
Hey, just wanted to thank everyone again for all the suggestions and support. Have been using glass syringe, incremental technique and focusing on going even slower than before, have not had any more wet-taps...(knock on wood) thanks for all the help
 
pgg said:
Don't lose faith, someday you'll be among the best and use hanging drop.
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I did an accidental hanging drop once. SAB for section on an obese patient. Musta hit a SQ vein with the introducer ‘cuz it filled up with blood. Put in the 25g whit, stylet out and it got blood in the hub too. I keep advancing all the way to the hub but no CSF. Push a little further indenting the skin and all of a sudden the blood in the hub gets sucked back in. I new was epidural. Coolest sh** ever.
 
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