Forearmed Is Forewarned — Bits and Bobs of the Plexus
Highlights
- Anesthetic Technique for Facial Plane Blocks
Transcript:
Speaker 1
Yeah. Okay. And then you'll just pop in a small volume of local anesthetic to surround it.
Speaker 2
Yeah. And in a way that I failed early on in these, when I first started thinking about these nerves and sort of scanning for them, Oh, there it is. And I got my needle kind of close and it didn't work. And I realized I wasn't close enough to the correct plane. So so it is a facial plane block. So I won't get my needle tip closer than nerve per se, but I want to definitely be outside the muscular compartments and in between those two, those two muscles. So oftentimes what I'll do is I'll go through and through the plane and then come back as I'm putting a little bit of pressure on the syringe and it'll sort of pop open that plane. Yeah. Do you do that? That's a really nice technique.
Speaker 1
And that I do exactly. And it just, it just reminded me of a statement that you made in one of our early podcasts when you said that famous line, all blocks are a facial plane blocks and that's kind of stuck in my mind. Right. Right. And before we move on to another nerve, I just wanted to sign post the fact that the median nerve gives off a branch, the anterior interosseus nerve. And that may well be relevant for part of our discussion that we're going to have later on. So I just wanted to sign post that here. Signpost. And that's responsible for muscle innovation and innovation of the radio owner and the wrist and carpal joints. So we'll come on to that. So what about the only nerve? Where can you block this only nerve then? (Time 0:20:19)
- Ulnar Nerve Block Technique Discussion
Transcript:
Speaker 2
Sometimes you can do one needle stick and get and just sort of redirect your needle over, but I'll find the owner typically on the ulnar side of the ulnar artery in that plane. Yeah. And as you get towards the wrist, they stay quite close together. So the artery is like immediately next to the nerve. And as you if you don't, if that kind of freaks you out a bit and you don't want to be so close to the artery with your needle, yeah, if you come back, just past midpoint of the forearm, they separate and you'll see the nerve take off. And that's, that's kind of where I like to do it. How about you? So you see, this is really exciting. The two things I want to say, as you were talking, I was, I was imagining exactly what, what I do and listening to what you do. So if I'm getting people to do an ulnar nerve block, I generally get them to start scanning at the wrist actually.
Speaker 1
Ah, what I say to them is, look, I say that identify the ulnar artery, because you know, you should be able to see that arterial landmark and look on the on the side of the ulnar artery. And that's when you should start to see the ulnar nerve. So I get them to get their eye in and they kind of look amongst the tendons and they say, is there a tendon? There's a nerve that I said, right. Now, keep your eye on the artery and scan proximal, come towards the mid part of the forearm. And exactly as you describe it, you scan from the wrist to the forearm, you will see the artery diverge from the nerve. It'll leave the nerve where it is right by flexicapial, naris. Right. See the ulnar nerve standing separate. And actually, if you're really clever and you, in fact, not at all, (Time 0:22:38)
- Identifying Ulnar Artery and Nerve
Transcript:
Speaker 1
Ah, what I say to them is, look, I say that identify the ulnar artery, because you know, you should be able to see that arterial landmark and look on the on the side of the ulnar artery. And that's when you should start to see the ulnar nerve. So I get them to get their eye in and they kind of look amongst the tendons and they say, is there a tendon? There's a nerve that I said, right. Now, keep your eye on the artery and scan proximal, come towards the mid part of the forearm. And exactly as you describe it, you scan from the wrist to the forearm, you will see the artery diverge from the nerve. It'll leave the nerve where it is right by flexicapial, naris. Right. See the ulnar nerve standing separate. And actually, if you're really clever and you, in fact, not at all, if you're really clever, if you pay attention and watch that ulnar artery, you'll see it dive past the median nerve. So you often watch that arterial branch branch. It will swing from the ulnar artery on the nerve and it will actually bypass the median nerve in the middle of the forearm. So I know one of my UK friends who did the fellowship with Vincent Chan in Toronto a long time ago, Matt Oldman, he published a little paper on this just showing or talking about how there's an arterial branch of swings from the ulnar nerve to the median nerve. So that's something to look out for. Yeah.
Speaker 2
Nice.
Speaker 1
The other thing I wanted to talk about is the fact that there is a very, or a couple of relatively common ulnar nerve, median nerve, cross innovation syndrome. So one of them is called Martin Gruber syndrome.
Speaker 2
And the other I think is called Ruganush. I'm not making this up. Googling. Yeah. It sounds, it sounds. Wasn't Martin Gruber the bad guy in diarchy? You know what? That also rings the bell. But I'm pretty sure I was Hans Gruber. (Time 0:23:20)
- Transcript:
Speaker 1
Yeah. Yeah. And that's a that's a nice way to go sometimes. That really is. But I again, I've got to remember how to say how to say this. Froge. I want to introduce some no, no, some controversy. Is that how I say I'm complete? Confused that. Well, I'm good. Yeah. I've confused now too. Kataña Salik has really got upset because I say controversy. And now I don't even know how to say it properly. But anyway, so something controversial. So you will be familiar with this whole concept of single double or triple cut crash phenomena when it comes to nerves. So one of the crashes being the potential use of a tunicae causing, you know, an area for nervous game. Yeah. And then you do a proximal break, your plexus block. That would be crush number two. Are we making it more complicated by doing these differential blocks and having another point along the nerve where we potentially exposes nerve to nerve injury? Do you think it's more risky to do to approach this, the nerve, at a long different path? Okay.
Speaker 2
So I have some, I have some feelings on this in opinions. So listeners, if you're unfamiliar with the double crush phenomenon, it's the idea that along the course of a peripheral nerve, you could have a subclinical injury. So most commonly people talk about a compression injury at the clavicle or first rib or at the nerve root level in the neck. So patients don't notice it until they have a second injury at some other point in (Time 0:34:31)
- Discussion on Identifying Veins and Nerves for Distal Radius Fractures
Transcript:
Speaker 1
No, it really works well, actually. One thing I've learned is actually cephalic vein doesn't lie is literally on the, on the anterior foot of the forehead, as you think. So again, I use a, the brachial artery in the median of as, as anchoring landmarks. And then I scan medial to identify the bazilic vein and go a bit more proximal. Sometimes you actually see the medial anti-bricul cutaneous nerve lying by the bazilic vein. If I don't, I just pop some local and say around it. And likewise, I look for the cephalic vein, which often sometimes sits above the midpoint of the anti-cubital fossa. And if you're really lucky, you'll sometimes see the lateral anti-bricul cutaneous nerve there. You know what I have done before is I've actually scanned from the musculic containers and over the axilla and traced it right the way down to the anti-cubital fossa and the largest branch, the last branch that's left is a lateral anti-bricul cutaneous nerve. So with a bit of practicing, you can see that. And do you know, I put a couple of videos on my, on my YouTube channel just to show how to identify those? So, oh, great. On this note, I, so I had a, I have a surgeon who sometimes doesn't like us using brachial plexus blocks for distal open reduction internal fixation of distal radius fractures. So, you know, I, when I first found this out, he was like, oh, you know, I don't want to proximal brachial plexus block, but you can do something peripheral. So I was thinking back in my early days when my anatomy maybe wasn't as good as it is now. I thought, okay, distal radius fracture, that's going to be radial nerve. Cause where's, what's that rule? Is it hunters rule? There's a rule about any nerve that passes by a bone will give innovation to that bone. I can't remember the name of that rule. Uh, Hilton's law. I think Hilton's law. There you go. Well done. Thank you for being so. I think Para, Parris Hilton. Yeah, Parris Hilton. (Time 0:51:41)
New highlights added June 16, 2024 at 2:52 AM
- Episode AI notes
- Anesthetic Technique for Facial Plane Blocks is crucial for nerve blocks, involving careful needle placement in the correct plane to administer anesthetic effectively.
- Ulnar Nerve Block Technique requires locating the ulnar artery as a landmark to find the ulnar nerve, ensuring safe distance for needle insertion.
- Identifying Ulnar Artery and Nerve is key in understanding the relationship between arteries and nerves in the forearm, with variations highlighted in a publication by Matt Oldman.
- Discussion on Identifying Veins and Nerves for Distal Radius Fractures emphasizes using anatomical landmarks and nerve tracing techniques to determine nerve locations for fractures, and preferring peripheral blocks over brachial plexus blocks based on Hilton's law. (Time 0:00:00)