Hello, and welcome to a third in a series of lectures on local anesthetic pharmacology and the application for central anoraxial techniques, in particular for obstetrics. I will tell you that this is my least favorite lecture, and it's the one lecture that's the most requested, and that is, how do we apply this in the clinical situation? In other words, you've got a mom in front of you, you need to make some decisions on how you're going to manage your pain, or how you're going to manage the anesthesia, and all of that's going to be related to the choices that you make related to the local anesthetic pharmacology, and the local anesthetics that you actually have available to you, and that's I don't want to minimize that. Much of the discussion and the decision making is related to what's on your formulary, and I'll come back to that in a moment. The reason I find this the least enjoyable lecture to give is because I think that it's really important that you understand that all of these decisions are made based off of the clinical context that's happening right in front of your eyes. I can't do that because I'm sitting in my office, and I'm recording this PowerPoint, and kind of giving you some guidelines, for lack of a better term, and as much as it galls me to say this, a recipe to at least get started with. I understand that it gives us a place to at least start the conversation, it gives you a place to at least start formulating a plan as you get ready to take care of these patients up on the labor deck or in the operating room. In that sense, I totally get it, I understand that. The problem that I have with that is that each clinical situation, the nuance of each clinical situation will dictate how you make these decisions, and it's really hard for me to be able to sit here and have a really intelligent conversation about these techniques because there is no clinical nuance to it, because this is a very sterile office-based environment, and that's not what you practice. So having said that, please just kind of understand from my perspective why it is that I dislike these kinds of lectures. I'm going to give you a place to at least start once we get in person and have the opportunity to talk about these, particularly amongst all of the different clinical faculty that you're going to engage with in the hands-on sections. Please have these discussions there because we all have a little nuance to our clinical practice. Things that work really well for me may not work for you, and that's okay. It doesn't mean it's wrong, it just means that it's not going to work in that particular clinical context. And so the breadth of your knowledge as you expand that gives you the opportunity to be able to transition with all of those different nuances. So having said that, let's get into this. As always, I have no financial relationships, and I absolutely will discuss the off-label use of local anesthetics and adjuncts in this presentation. So these are the learning objectives that are given. I covered the first four in the first two local anesthetic lectures. Basically what I'm going to talk about here is the clinical application of the local anesthetics. I'm not going to really get into the pharmacology. Let's just talk about how do we use these in our clinical practice. And so I really think the first thing that you have to decide is why is it that you're using this? Now obviously that's really pretty straightforward when you're up on the labor deck and you get called in because mom's in pain and you're going to do a labor analgesic, whether that's an epidural, whatever it is that you're going to do, versus is this going to be your primary anesthetic? This is an operative delivery. We're going to the operating room. Those are two very different clinical situations, and you're going to have different priorities based off of those clinical decisions that you're making. Obviously onset is always going to be a priority. Moms want to get comfortable, and that's why we're there. That's our obligation is to get in there, be safe. I'm not saying cut corners or anything like that, but we have to be relatively efficient, and we need to get mom comfortable pretty quickly. Now I'm not saying you need to get mom comfortable within a minute, but certainly within 10, 15 minutes from when you get in there, you should be doing something to make mom much more comfortable. So onset will always be part of the equation. Now duration, it depends on, again, was this our primary anesthetic? Is it a one-shot technique versus a catheter technique? And we'll get into all of that kind of stuff. But I think really the most important decision that you need to make is what is the clinical situation? And routine is fine. We'll talk about routine, but is this urgent versus is this emergent? And so we'll talk about that. Really when we start thinking about urgent versus emergent, sorry for going back on you there. I really think this discussion is not something that is going to happen to you with one rare exception that I will talk a little bit here on the labor deck. This is really when we're talking about operative delivery. So I'm going to talk about operative delivery first because I think it's the most straightforward. Really operative delivery comes in two forms. There's either a planned, scheduled, or kind of identified upon admission to the labor deck. All right. Oops, this patient's breach. All right. Well, now we're going to the OR. This is planned. It's routine. It's not urgent for the most part. I mean, there are times where patients will walk up onto the labor deck and it's truly emergent. We'll talk about that. But I really think that we need to break this down from an anesthesia perspective. Remember, this is the anesthesia perspective. I'm not an obstetrician. I have lots of experience with this and I'd like to argue with the OBs quite a bit. But it really comes down to, is this urgent or is this emergent? And there is a very different mindset to this. I would say that regardless of how we end up in the operating room, if we just look at all of the operative deliveries across the United States, and again, our C-section rate is approaching 40%, which is a lot, a lot of C-sections. I would say that probably 95% of those are urgent. There's probably only two or three or maybe 5%, depending on your practice and where you're practicing, that are truly emergent. I can think of, in my 30-year career of doing obstetrics, I can think of five truly emergent operative deliveries that I've been involved in. Now, I've been involved in a lot of touch-and-go situations where there's a lot of anxiety. This is urgent. We need to get going. But truly emergent, I think, is really a very, very small part of our clinical practice. When we get to this situation and we're taking mom into the operating room, as I suggest, there's two forms for operative delivery, planned, routine, and urgent. Sorry, I'm writing with a mouse. It's kind of hard. I group these two together versus this. Those are the kind of two flavors. There's also two flavors with mom. There's mom that comes in, has nothing in her bag, versus a mom that has an existing epidural. I'm going to talk about each of these situations separately. If this is truly emergent, and again, that's why I highlight this, if this is truly emergent, you need to put mom to sleep. You need to do a general anesthetic. You need to intubate her, secure her airway. You need to do that doing a rapid-sequence induction. I'm not going to get into all of the different airway manipulations, whether you're a video laryngoscope person or a standard DL, all of those kinds of things. You all know that in your clinical practice. You know what you have access to. But I will say that in those five cases that I can think of in my career that were truly emergent, I did general anesthesia and secured the airway in all five of those cases. Now three of those cases were before the invention of the video laryngoscope. One of those was a miserable airway, and I truly wish I had had a video laryngoscope. I didn't, but we were successful and it was okay. But again, this is where you really have to know your clinical environment, and that's different. Everybody is different. So I can pontificate about what I would do in my operating room, but that's completely different than what the experience that you're going to experience is in your operating room. So my suggestion is think this through. If tomorrow you're at work and you have to take a truly emergent mom or truly a mom into the operating room for a truly emergent operative delivery, how are you going to manage that airway? How are you going to manage that anesthetic? Think about your plan A. Think about your plan B. And more importantly, what their plan B is, can you touch your plan B? I've talked to a lot of people and they say, you know, geez, you know, my plan A was great, but I got in there, everything went sideways, I went to do plan B, and we didn't have a bougie in the room. I had to call somebody for a bougie. Well, you know what? As mom is starting to desaturate, that's not the time to be calling out and have hoping that somebody can run to the workroom and find you a bougie if all you can see is, you know, epiglottis. So thinking these things through, knowing what your plan A is, knowing what your plan B is, but can you touch plan B? Is it in the operating room for you? I can't emphasize that enough. I can't tell you how many Cs and providers I've seen get into trouble because they just assume that they'll have plan B available. So think it through, make sure you have plan B, make sure you can touch plan B. And that's for a truly emergent cesarean section, you know, a truly emergent operative delivery. You just need to put these moms to sleep. Don't let anybody come into the room with them. Yes, it's emotionally charged. Yes, they're going to be really angry with you. But you know what? Once it's said and done, I've never had a mom complain because I put her to sleep. So just something to think about. Now, if it's urgent or routine, you've got time. Yes, even if they've had some D cells, as long as the baby is recovering, you've got some time. And depending on how savvy you are with these techniques, I mean, obviously if you've only done, you know, 10 or 15 spinals, you may not have time. But if you've done 100 or 1,000 of these, I can actually probably sit a mom up and get a spinal in her faster than you can take her in, get all the monitors on, do a true denitrogenation, and then rapid sequence them. So again, this is, you know, it's based off of your skill level. It's based off of the support that you have within the operating room. Is there somebody that's going to be available to help you with this, particularly hold moms still for positioning? Will your OBs give you a little bit of time? Again, I've worked with the same OBs forever. So I have a relationship with them. And if I tell them, hey, I need five minutes to get a needle in their back, they're going to groan, you know, you know, F in anesthesia and all that kind of stuff. But they'll give me the space to at least get a needle in this mom's back. So again, based off of your clinical parameters, you need to make these decisions. So when I start thinking about dosing a spinal anesthetic, I would say that probably 90% of spinal anesthetics delivered in the United States or a Caesarean section are somewhere between 10.5 and 12 milligrams of hyperbaric bupivacaine. And why is that? Well, it's because it's what's in the kit. It's easy. It's very reliable. We know that the kinetics are going to be pretty simple. They're pretty reproducible. Generally, usually most of the time, you're going to get a T4 block with some degree of variation in there. And for the most part, these work very well. And candidly, at 2 o'clock in the morning when I really am tired and I don't want to think, this is my go-to. Why? Because it's reproducible. It's easy. I don't have to think much. And I can get away with this with minimal effort. And that's fine. There's nothing wrong with it. Now, the other thing that you need to consider is not only is it the urgency of the situation that you're going into the operative delivery for, but you also have to know your operative team. And what I mean by that is how long is this C-section going to take? Again, I freely admit I'm in private practice. I have no learners. My surgeons are very savvy. An operative delivery in my clinical practice is a 20-minute case, skin to skin. Now, obviously, we've got to get the surgeons in the room. We've got to get prepped and draped and positioned and get the baby daddy or the support person into the room with mom and all that kind of stuff. So I'm not saying that we're only 20 minutes in the room. But I'm saying once we go, once we cut skin, from skin to dressing is about 20, 25 minutes in my clinical practice. So a lot of what I am talking about is based off of that clinical parameter. So again, think about what you're in. If the medical student's going to close, you probably need to do a CSE and thread a catheter in their back because that wound will granulate before the medical student's finished closing. So again, very different clinical parameters that you're making these decisions from. So I would say that this is very comfortable. It's very easy. Most people are going to do it. There's nothing wrong with it. It's very reproducible. The question is, what are you going to add to this? Now, we, I am still with about half of my surgeons, half of my surgeons will let us do intrathecal morphine as part of our subarachnoid block for a cesarean section. I know a lot of places are really moving away from using intrathecal morphine because of all of the side effects and because of all the bad press. A lot of places are going opioid free. And I do have a little bullet down here in a minute that I'll talk about. But I would say in about 50% of my C-sections, I'm still using preservative-free morphine. I'm using 150 mics. We used to dose much higher than that. As a matter of fact, we used to use half a milligram when I first started. And those ladies were miserable afterwards. They would have nausea and vomiting. They would have wicked pruritus. It was miserable. So then we backed down to 0.3. That made it better, but not great. Then we backed down to 0.2. And that was really, really nice. That seemed to be the sweet spot. And actually now backing down to 0.15 or 150 mics, I see the same analgesia, not quite the duration that it used to be, but certainly really good analgesia for about 18 hours. And I have not seen any side effects, most notably pruritus or postoperative nausea and vomiting related to the morphine when I dose it at 150 mics. The new kid on the block is dexmedetomidine. If you're going to dose dexmedetomidine in the spinal, the dose is 5 mics, as I show you down here. I'll talk about that in a moment. I would just caution you, particularly if you're using bupivacaine, if you add dexmedetomidine to bupivacaine, you're going to have an 8-hour block. And some ladies start to get a little annoyed with us at the 6-hour mark if they still have two dead legs. They've got this newborn and they're trying to do all of this stuff. And of course, OB is pushing all of this skin-to-skin stuff, and they want to be able to breastfeed and do all that stuff, and they've got two dead legs. So just think about that. There is some kind of controversy related to that if you're going to use dexmedetomidine. Remember, if you use dexmedetomidine, you're going to absolutely extend the duration of your block by at least 30%. The nice thing about adding dexmedetomidine and why it's one of my new favorite drugs is that you get a much denser block. Anytime that I have added dexmedetomidine, I have never had a hot spot or I've never really had kind of a shaky block where I'm kind of having to work around some areas where they're having some discomfort or some pain. Now I will talk, we do a whole lecture on the in-person side where I talk about identifying an inadequate spinal or epidural and some strategies on how to deal with that. So I'll have a much more robust conversation about that when we're in person. Now again, depending on where you're working, remember, I'm doing this, it's a 20-minute case. I'm really, unless I'm super, super tired and I haven't had much time to set up, again, I take call from home. So sometimes I get there and they've already got the patient in the OR, which is really annoying, but it is what it is. I'm a big fan of Mepivacaine. Again, this is my clinical practice. I can get away with it. So I like 50 milligrams of the 2% Mepivacaine. It's isobaric. It's going to stay where you put it. You're not going to get much higher than T6 with this. So if you really do need something a little higher than that, you might push this to 60 milligrams. So this is two and a half mils of the 2%. You can go up to three. That's a big dose. You're going to get up to T4, maybe even a little higher with that dose. So just be gentle with it. Or you can use the isobaric Mepivacaine. What's nice about the 12 milligram isobaric Mepivacaine, which we found out when the hyperbaric Mepivacaine was on back order, is that we had a really consistent block, but the block didn't get up to T4 as often. With 12 milligrams of hyperbaric Mepivacaine and you lay them down, you're going to get to T4, sometimes even to T2, and that can be pretty disconcerting for mom. This is pretty reliably going to give you T6. So something to think about. The reason I like Mepivacaine is it gives me 90 minutes. And so I know that these moms are going to be recovering by the time they clear PACU and are getting up to OB. So our OB is up on the third floor. Our ORs, we do all of our operating deliveries in our main OR down in the basement. So by the time they clear PACU and get back up to the third floor, they're already moving their legs. Now, if you want to go opioid free, there's nothing wrong with that. You can use the hyperbaric Mepivacaine or the isobaric Mepivacaine if you're in a academic practice where it's going to go on. I use, again, the 50 milligrams of the 2% Mepivacaine. I add five mics of dexmedetomidine. Now this extends my block to two and a half hours, almost three sometimes. But I get a really dense block. Moms are very comfortable. And then what we do is I just do tap blocks, 5-hour tap blocks in the PACU. The nice thing about doing the tap blocks in the PACU is she's numb, right? She's got a T6 block, so she doesn't feel anything while I'm doing the tap blocks. I will tell you though that of all of the tap blocks that I do in my clinical practice, these are the hardest tap blocks to do because if you think about their anatomy, they've had this gravid uterus in the pelvis for the last nine months, which has really stretched their abdominal musculature. And getting into that fascial plane between internal oblique and transverse abdominis can be pretty challenging in a really boggy, really low muscle tone abdomen immediately post-delivery. So just kind of keep that in mind, but that is also an option. So if you're not going to do morphine, then we do tap blocks in the PACU. And we've had pretty good response with that. Again, we typically get about 18 to 20 hours of really good analgesia after an operative delivery with our tap blocks. Now I know a lot of you will want to do a CSE. That's fine. The thing with this is your intrathecal doses are exactly the same as what I've talked about here. There's really no difference. The thing is, you have to thread your catheter, always, always, always thread your catheter. And really there's kind of two reasons why I would consider doing a CSE in the operating room for an operative delivery. And again, if I'm doing a CSE, this is a mom that had nothing in her back yet, right? So I sit her up, I get the epidural needle into the epidural space, I go through the epidural needle with the CSE needle, and then I do my IT dose, right? And then I back it out, and then I thread my catheter. So there's two reasons why you might want to do this. Again, this is not my clinical practice, but it may be yours. And that is you need to extend your anesthetic beyond whatever it is that you've used here. And that is absolutely reasonable in the academic setting, particularly if you've got a first-year resident that's doing the cesarean section, and then you've got a medical student that's closing. Don't forget that if you're going to transition, then, from your IT dose to your catheter, you should test dose your catheter first. You can do that in the operating room. You can't do it if you've done an IT dose, and then take your epidural, and then lay her down. Test dose your catheter until that block is starting to regress a little bit. Then you can absolutely test dose it, and we can talk about that when we're in person. The other way that you might want to use this is if you're going to convert this to post-operative analgesia, and then you just run it like a regular epidural. This is really starting to fall out of favor in that most surgeons are not allowing us to run epidurals after the operative deliveries anymore, which I think is a shame, but it is what it is. The changing demographics of anesthesia practice, and all of this early ambulation, early rehab, all of that kind of stuff, so it's fine. I'm not going to argue politics. If they don't want an epidural, then you just do the tap blocks, or you can put intrathecal morphine, or you can do epidural morphine, for that matter, and then pull your catheter. Now, this is where it gets a little dicey, and I'm probably going to irritate some of you. We're going to have a much more robust discussion about this when we're in person, but how do you convert a functioning labor epidural for the transition from laboring epidural, in other words, labor analgesia, to an anesthetic for an operative delivery? The key word here is functioning. You have to have a functioning epidural. I will tell you that in my practice, I just don't do this. I will show you data that at eight hours, about 30% of labor epidurals are going to fail, and it doesn't mean anything. It's not that you're a garbage human being. It doesn't mean that you have horrible technique. it happens to even really experienced providers. It just happens. It's just the dynamic of labor that all of the physiologic changes that are happening, all of the movement that is happening, all of the sympathetic, you know, stimulation and all that kind of stuff, the sweat, all of the fluids that are part of this whole dynamic process. And we know that 30% of these epidurals are going to fail. Alright, the last thing you want to do is take a mom into the operating room, have the surgeon start the procedure, and then realize that your labor epidural is failing. That is just a heartbreaking situation for everybody involved. And then it becomes a crisis, right? And we want to avoid a crisis. So really, really think twice about doing this. Again, I'm just not a big fan. So here's how I approach this. Again, this isn't the right way. It's not the only way. It's simply a way. It gives you an idea of how to start thinking about setting yourself up for success. So if it's a catheter that I put in and I know it's been working well, right, I'm still really nervous about converting this. What I do is I make this epidural declare early. And what do I mean by that? I give a big test dose. Scratch three here. Use five mils of the one and a half percent lidocaine with one to two hundred thousand epi, right? This is, if you give a good five mil dose of this, right, you will know within a couple of minutes whether this epidural is going to work. Because you're going to transition from an analgesic to an anesthetic, right? Their legs are going to get weak. They're going to absolutely going to see significant changes. And so I do this. I give them, I make sure I want to declare early. I want to know very quickly if this epidural is going to work. And then if it does work, then I start with a little bit lower dose. Then I will transition to the three mil for subsequent doses until I get up to about a T6 level. And then I stop and then reassess as they're getting, as they're prepping. We've got in the room position, perhaps left uterine displacement, all that stuff. The drapes go up and then I do my final test. And if I'm not at least T6, then I can give a little bit more. But that's at least enough to get you started. And so that's how I kind of look at this. If I give this first dose and I'm seeing either a no or an equivocal response, right, then I just replace it. Right, I just don't mess around. I sit mom up, I pull it out, and I do a single shot spinal. But that again is my perspective. I'll show you data on how, on why all of this happens, and then we'll talk about various different ways of managing this when you're faced with this situation. But again, just from a dosing perspective, right, I'm really supposed to just be talking about how do we dose these local anesthetics. This is how I manage this because this will make that, your ability to make this epidural declare that it's going to work very quickly. Now, for labor analgesia, this is a little bit dicey because there's so many different ways to manage this. And again, almost all of this is going to be predicated on what's in your formulary. In other words, when you go up onto the labor deck and the nurses are going to pull whatever the epidural solution du jour is from the PIXUS, that's what you're going to use, right. We have very little impact on our ability to change what the pharmacy stocks up on OB. Now hopefully, you know, you've got anesthesia involvement in your P&T committee at the hospital. Even though we were sitting on P&T, we kind of got relegated to using, whoops, sorry, 0.2% ropivacaine with two miles per mil of fentanyl. And we have these special epidural pumps that are locked, again, because of the fentanyl and because of all the opioid abuse, blah, blah, blah, blah. And so these come in cassettes. And so I have like no control over this whatsoever, other than the fact that I'm really blessed in my practice that I know the OB nurses really well. So if they call me in the middle of the night and I drive in, I know that they've at least pulled the cassette and they primed the pump for me so that when I do place the epidural, all I have to do is hook up and off we go. I like to run patient-controlled epidural analgesia, so PCEA, right. This gives the moms some control and they really enjoy that. And then I will tell you that I almost never do CSEs. I'm not a big fan of CSEs up on the labor deck. And so here's why. I think that the problem with the CSE is the transition. And I don't think we spend enough time, nor do I think the moms are able to appreciate it, particularly if they're in pretty significant pain. I don't think they're able to appreciate our discussions when we talk about the difference between the intrathecal dose and the epidural dose. And what I have noticed in my practice, again, this is just me talking. I'm not trying to dissuade you. I'm simply sharing my clinical experience. And my clinical experience is that the moms that I've done CSEs on, where I've done an intrathecal dose, are never as happy with their epidural as they are with the intrathecal dose. And it sets you and the mom up for false expectations and for some difficult conversations. And so I think in my mind there's really only two times that I will do an intrathecal dose or that I'll do a CSE. And we can have that discussion because, again, I'm going to talk about that when we are in person. But those two situations are, the first is when I walk on the labor deck and I've got a mom that is completely out of control. And I mean, you know, the pain is just so bad that, you know, it's just they are completely out of control. They're not processing anything. They can't process anything. All they know is that this really, really hurts and they just want to be comfortable. And what I do is I get in front of them and I kind of get aggressive because you have to to get their attention. I look them in the eye and I say, you need to sit still for two minutes. I'm going to stick a needle in your back. I'm going to get you comfortable and then we'll have a conversation. And essentially what I do is I just do a single shot spinal and I inject my intrathecal dose. I'll talk about what my intrathecal dose is in a moment. I get them comfortable. They get comfortable in about 60 seconds. And all of a sudden they become this delightful person. Then I have a very different kind of conversation and say, okay, as I promised you, I got you comfortable. Now you need to let me put an epidural in and then I put an epidural in. So I think that's one case where I would do an intrathecal dose or a CSE. And in that case, I'm really not doing a CSE. I'm just doing a single shot spinal to get in their back, get them comfortable. And then I go back in with an epidural. The second time that I will do an intrathecal dose is if I've got a multip and they're late, right? And what I mean by late is that they have progressed really far in their labor. They're probably eight, eight and a half centimeters, maybe even nine centimeters by the time. They might call me and they're at seven, but this is a multip and they're going really fast and I get there and they're at nine, right? I will do a CSE in those particular cases. I will caution you though, if you're going to get in that mom's back, thread a catheter. I have been burned on more than one occasion, even with grand multips where, oh, you know, this baby's just going to fall out. Just, just put an intrathecal in. I guarantee they're going to deliver in 20 minutes. And then, you know, three and a half hours later, we go to the operating room for an operative delivery. So if you're going to do this, always put a catheter in their back. So I'll talk about the, just how I manage the PCEAs first. There's, again, no science to this. This is just my clinical experience. I can't highlight this enough, please, right? This isn't the right way. It's not the correct way. It's not the only way. It's simply a way to do this. So how do you determine what the rate is going to be? That's really the option here. Your, your drug choice is going to be dictated by pharmacy. So again, thinking about what I just said, I have 0.2% ropahucanin, 2 mics per mil of fentanyl. I don't have an option with that. That's what I use. Now, as far as dosing, how do I manage that? The textbook suggestion is one and a half mils to two mils per segment. Now, I would put to you that if we went into Epic and pulled a thousand labor epidural notes out of Epic, 999 of them would say that the, we put the epidural in at L3-4, right? The reality of that is that we have really no idea where we put that. That's a whole nother separate conversation. But, you know, if we think about this, this pain, particularly for the first stage of labor, we're talking typically from T10 to L2, according to the textbooks. I don't necessarily agree with that. I think it does extend lower into the lumbar segment. So I like to think of it as from T10 to L5, right? So we're talking seven segments, right? The five lumbar segments, and then, you know, T10, 11, and 12. Okay, so eight segments, right? So if you're doing one and a half per mil, mil per segment, right, we're talking 12 mils an hour. And that seems like a lot to a lot of people. What if we pump that to two mils, right? We'd be talking 16 mils an hour. And that's what the textbook suggestion is. And so I think we probably, for the most part, under dose moms, because we're just really conservative, and because these are big volumes, and we don't like big volumes because of lots of different reasons. So I have kind of come up in my own feeble little mind with a way of trying to figure out, you know, really, what you need to understand is, you know, and this varies by patient, every patient is different, but how much volume is in the epidural space? And that's going to be different in every patient, right? So how can we tell that? Well, why not use how much volume it takes us to get them comfortable as at least a starting point for how we're going to dose our epidural? And that's what I do. So I put the epidural in, and I like to give a full five mil test dose. So I use one and the five mils, the whole vial of the test dose, one and a half mil, one and a half percent lidocaine, one to two hundred thousand epinephrine. I give all five of it in, I tape everything up, I let mom lay down, I hook up the epidural, and then I test. I don't actually test the height of the block, I simply ask them what their pain scores are, right? And so this we can get into, we'll talk about this, you know, setting reasonable expectations, and so generally most of the time when I get involved with this patient, it's usually a nine or a ten out of ten. After the test dose, it might be a five out of ten. I say perfect, see we're already making progress. If on the rare occasion they get comfortable, and my goal is a four, three or four is what I always tell them, I always, we always agree to that before I ever stick anything in their back. If I get it to a four on just the test dose, I just hook up and start running, and what that tells me, what that tells me is that they have a relatively small volume in their epidural space, so I can run a relatively small volume of an infusion, and again I always, sorry my mouse is really twitchy right now, I always use bolus of 50%, so if I'm going to run them at six mils an hour, then I give them a bolus of 50% of that, which would be three mils, and I give that to him every 15 minutes. I give them the button, and generally most of the time I don't get a lot of phone calls related to this. Now if I have to give a second dose, now when I say I'm giving a second dose, now I'm transitioning, I'm not using the one and a half percent anymore. Now my second dose will always be the epidural solution, and what I do is I hook up my epidural catheter to the pump, and I can do a clinician bolus through the pump, and I give them another five mil bolus. Now this is the 0.2% ropivacaine with the two mics per mil of fentanyl. If they get comfortable on that second dose, then I bump this up, because now again I put about 10-ish mils in their epidural space, so I run eight mils an hour with four. If it takes me three doses, again I've got about 15-ish mils in their space, so then I run 10 mils with five every 15 minutes, and that seems to work fairly well. It's rare that I have to give more than three doses. If I have to give a fourth dose, I will pump this up to 12. I do get a little nervous with those kind of infusion rates, but you can see that's still well below the textbooks. If I have to give a fifth dose, then I start worrying about, is my epidural in the right space? And so we can talk about that conundrum later, but this at least gives you a starting point for how do you figure out what it is that you want to do and how you're going to manage that. Now I know you all want to do CSEs, and I know you want to do interest-equals. That's fine. So here's my interest-equal dose. I use one mil of the 0.25% bupivacaine with 25 mics of fentanyl in it. So it makes the math really easy, right? So it's 2.5 milligrams of bupivacaine, 25 mics of fentanyl. It's one and a half mils total volume, and if you inject that into the subarachnoid space, your mom will get comfortable in 60 seconds. And then they're going to relax. They're going to let you do whatever you want. You're their new best friend. And then I always thread a catheter. I don't care if this is a grand mal tippet 9, right? Thread a catheter. I have never been sad that I had a catheter in a mom's back, right? You know, they delivered. That's awesome. I go back later, and I just pull the catheter out. No big deal. But I've been really sad if I've not put a catheter in, and I've gotten burned twice on that now. And so I always thread a catheter. The one thing that you have to do is you have to plan for that transition, and you have to have a discussion with this mom with that transition. And what I mean by the transition is this is going to last somewhere between 90 minutes and 3 hours. It just depends. Everybody's a little different, but at about the 2-hour point, I'm thinking I got to do something here and have a conversation with the mom and tell her that there's going to be a transition, that the epidural is going to be a little different. Don't say it's not going to work as well because then you've already implanted that in their head. What I tell them is it's going to feel different because the medication is in a different space. And just have them plan for that transition. A lot of times what I'll do, particularly if this has been early in their labor, as I suggest a mom that's completely out of control, what I'll do is once I put the catheter in, I usually just start the catheter on the infusion. I just run the infusion, and that helps to minimize that transition a bit. Now when we start talking about top-offs, this is where it gets a little uncomfortable. And we'll talk about this again in the in-person part as well. If I get called up because all of a sudden mom's got breakthrough pain, the very first thought in my mind is this is a catheter that's failing. And so you have to make sure your catheter is working. I don't mess around with this. As I said, I make these catheters declare themselves quickly. So you have to make sure your catheter is working. You have to do it quickly. You have to assess, and you have to communicate. Communicate with mom. All right, don't just go in there and mumble to yourself, right? She knows that this isn't working well. That's why they called you. She's in pain. So there's been a transition. There's something that's different. So let's assess this. Let's communicate. I talk to her. I talk about the decisions that I'm making and why I'm making these decisions. I engage them in those decisions. And that just gives them some control. It lets them know that you have their best interest in mind. It lets them know that you are doing something to make them comfortable. And that, I tell you, that's 90% of the battle, right? If you've got, if you're developing that relationship, if you're developing that trust, they're gonna give you the time to do what you need to do. If you go in and blow them off, they're not going to be real happy with you, and they're going to actually be more difficult to get comfortable. So if I have any doubt about this catheter, I give the 5 mil test dose, right? That's the 1.5% lidocaine with 1 to 200,000 epi. And I know within five minutes whether this catheter is going to work or not. There is no doubt. It's absolutely objective. And if there's no change, I just say, you know what, it just, the catheter is probably not in the right space anymore. We just need to replace this catheter because I want to get you comfortable. And I have never had a patient argue with me. So I sit her up, I pull the catheter out, and I replace it. I just don't mess around trying to salvage it. I used to do all kinds of flips and twists, you know, try different concoctions, try more volume, lay them on a different side, you know, do all of that kind of stuff. And you know what would happen? I'd spend 30, 45 minutes in there. The mom's uncomfortable, I'm uncomfortable, the OB nurse hates us. And what happened 45 minutes later? I sat her up, I pulled the catheter out, I replaced it. So I do it in five minutes now. I give it one good shot. If there's any doubt in my mind, I just sit them up, I pull it out, I replace the catheter. Now if it's working, what do you do? So if I give the test dose and now I see some response, now I know I've got a working epidural. I think it comes down to, again, this isn't the right answer, it's not the only answer, but this is the way I approach this clinical conundrum. I think it's either a volume problem or a concentration problem. And this is where the assessment comes in. I like alcohol, right, the hot-to-cold transition. And so I just test my spread. Do I have at least a T10 level? If I don't have a T10 level, then it's, that's pretty straightforward. It's a volume issue. I need to top off that space. So I give another bolus, a clinician bolus, through the pump and now I jack my rate up. I've just proven that that volume, that infusion isn't enough to keep that epidural space filled. If it's, I've got adequate spread, now it's a concentration issue. This becomes a little bit more of a conundrum and you really have to be careful where you are in the labor, right. So, you know, if this is a mom that's at eight, the last thing you want to do is, you know, use a pretty heavy local anesthetic, meaning a heavy concentration, make them weak and now they can't push when they get to complete. So this is the tightrope. This is where it gets really challenging and there's so many different ways to manage this. But again, I like to make sure that this, I declare this, I like that at this point to go just straight, the straight 0.25% bupivacaine, that's isobaric. And a lot of people will argue that according to the textbooks that 0.2% ropivacaine and 0.25% bupivacaine are equal in concentration and effect. I will tell you that in my clinical practice and my clinical observation is that that is not true and that every time that I've used 0.25% bupivacaine just to kind of up that concentration a little bit, that's been enough to really get me through that particular crisis. The last thing that I'll say about top-offs is if this is the third time you're going up to top off a catheter, by all means get that mom comfortable. But once you're done getting her comfortable, you need to go down and set up the OR because that's almost guaranteed that you're going to end up as an operative delivery. And there is a direct correlation, I'll show you the data, there is a direct correlation between the number of top-offs and the incidence of operative delivery. So there is something about that labor, there is something about the dynamics of that mom's pain and their labor that lead us to an operative delivery for whatever reason. We don't understand that causation or that correlation but there is a direct correlation between the number of top offs and operative delivery. So go ahead and get your OR set up and have a plan for that. Now what do you want to do at 9 centimeters, right? This is always the question that I get asked a lot and up until recently I really didn't have a good answer. There really wasn't much that we could do at that point. A lot of people would get a hundred mics of fentanyl, dilute it in five mils and blast that in and that helped but it wasn't great. You know the problem is at nine centimeters we can't make her weak, right? If you take away her motor at nine centimeters they're just not going to invite you back to OB very often. So you had to be really careful. Now we do have a new kid on the block and I do have an answer finally and this is my answer, right? Take 20 mics of dexmedetomidine, mix it in five mils of saline and give it through your epidural catheter. Now I will tell you you have to stay with this mom for a good 15 minutes. This will absolutely calm down and get them through that transition from the first stage to the second stage of labor and it will let them push. There is zero, zero motor component to this. However, sorry my mouse is really twitchy, I don't usually see bradycardia with this but you need to track that and so you know I actually make them put mom on a ECG monitor. I just do a three lead when I put the epidural in and during the test dose but they take that off as soon as I walk out of the room but make sure your pulse ox is on and make sure you're following mom's heart rate. I don't usually see bradycardia but you will see hypotension with this so have some ephedrine available or phenylephrine whatever your drug of choice is. A lot of times it takes both. You will see hypotension with this so just be careful but this will absolutely get them through that transition and delivery and they won't be weak. It's my new favorite. So something to tuck in the back of your head. Be careful with this though. You will see some hypotension. And that is all I have. We will do a much more in depth discussion about these things in the in-person section and you'll have plenty of opportunity to pick all of our brains on how we manage all of that stuff. And that's all I have for you so thank you for your attention.

local anesthetics

obstetrics

central neuraxial techniques

bupivacaine

dexmedetomidine

cesarean sections

labor analgesia epidural

obstetric anesthesia