Episode 53 — Analgesia for C-Section With Mike Hofkamp
Highlights
- Anesthesia for Caesarean Delivery
Summary:
We're going to talk about indications versus area in section, distinguish between urgent and emergent Caesarean sections. Aztec techniques and complications we're going to discuss the difficult airway and obstetrics; aspiration prophylaxis. So I like to break the indications for C sections down into maternal factors and fetal factors so for maternal factors failure to progress andfetal factors such as heart rate or blood pressure can be an indication that someone needs a C section. We'll get some good learning here to help out with that. Sounds great I'm looking forward to it too. Well you know when I give my residence lectures I'm always focusing on for better or worse on the A
Transcript:
Speaker 1
Well you know when I give my residence lectures I'm always focusing on for better or worse on the ABA outline so just to go with the ABA outline real quick we're going to talk about indications versus area in section we're going to distinguish between urgent and emergent Caesarean sections we're going to talk about Aztec techniques and complications we're going to discuss the difficult airway and obstetrics and then finally we're going to talk about aspiration prophylaxis.
Speaker 2
Great I think this will be great and you know I'm really looking forward to this because I remember as a resident this was definitely something that came up a lot and one of those feared kind of moments as a resident on OB is that crash C section and maybe you're attending is a few floors away and a lot of thoughts running through your head about should you intubate or not do you wait for your attending or not so I think we'll get some good learning here to help out with that.
Speaker 1
Sounds great I'm looking forward to it too.
Speaker 2
Alright so why don't we start as you said with indications I think that's always a good place to start so tell me about the indications for anesthesia for Caesarean delivery obviously the most obvious one being someone who needs a C section but what do you think about when you think about kind of the indications.
Speaker 1
So I like to break the indications for C sections down into maternal factors and fetal factors so for maternal factors failure to progress (Time 0:00:42)
- Persistent Fetal Bradycardia
Summary:
We're becoming less and less comfortable with breach delivery but vaginally using forceps or other methods. So we're now going more toward a C section kind of automatically for thoseYes yes I say that's a fair statement all right another field factor is the so-called non reassuring fetal heart rate. These account for about 23% of the indications for Cesarean section.
Transcript:
Speaker 1
section got it okay so we're becoming less and less comfortable with breach delivery but vaginally using forceps or other methods and so we're now going more toward a C section kind of automatically for those yes yes I say that's a fair statement all right another field factor and probably the most important one is the so-called non reassuring fetal heart rate these are the the so-called decelerations that occur in conjunction with the urine contractions and they're an indicator of fetal non well-being and they are somewhat open into interpretation and so one obstetricians interpretation of a non reassuring feel heart rate may not completely correlate with a different obstetricians assessment nonetheless these account for about 23% of the indications for Cesarean section and (Time 0:09:46)
- Is It a Stat or Crash Cesarean Section?
Summary:
In my experience they're not going to let a baby be in the 60s for more than a minute or two before they're making moves to go back. There are some indications for urgent cesarean section that are more timely than others like for instance non reassuring fetal heart rate is. and might does it matter how long it's down in the 60, if so? Is there a definitive cutoff or does it depend from obstetrician to obstetrician I believe it's judgment but in my experience most babies will recover by the time they get to the operating room.
Transcript:
Speaker 1
and might does it matter how long it's down in the 60s and if so is there a definitive cutoff or does it depend from obstetrician to obstetrician I believe it's I don't I'm not aware of any specific cut off I believe it's it's judgment but in my experience they're not going to let a baby be in the 60s for more than a minute or two before they're making moves to go back in fact there's a lot of times where they will go back and by the time they get to the operating room the heart rate has recovered and they say thank you for showing up we're actually going to go back to our labor and delivery suite we just wanted to make sure we were back here to start if it persisted okay fair enough so what happens with those really urgent or emergent C sections what makes something urgent or emergent and you know how do we think about those so urgent C sections are C sections that really should be done within the hour and they can have many shades of gray I'll call it so an urgent C section to me is in the eye of the beholder there are some indications for urgent cesarean section that are more timely than others like for instance non reassuring fetal heart rate (Time 0:11:03)
- Are Urgent Cesarean Sections More Timely Than Others?
Summary:
An urgent C section to me is in the eye of the beholder there are some indications for urgent cesarean sections that are more timely than others. Failure to progress can turn into anurgent or emergent C section and heartbeat so it's very difficult to exactly quantify which is better. ACOG says that the the so-called decision to cut time that mean I'm an obstetrician should be 30 minutes or less.
Transcript:
Speaker 1
those so urgent C sections are C sections that really should be done within the hour and they can have many shades of gray I'll call it so an urgent C section to me is in the eye of the beholder there are some indications for urgent cesarean section that are more timely than others like for instance non reassuring fetal heart rate is an indication for an urgency is our in section so is failure to progress now non reassuring fetal heart rate is a little bit more urgent than failure to progress but failure to progress can turn into an urgent and more urgent or emergent C section and heartbeat so it's very difficult to exactly quantify which is which is more important than the other but for in typically speaking for an urgency section you want to go the operating room as soon as possible within the hour and the Aztec implications are that you are almost always able to do a regional technique a regional technique could be a single shot spinal or a medication to an existing epidural now in contrast any emergency section is a C section that really needs to be done as soon as possible now there is a national standard of care for emergent cesarean sections and so ACOG says that the the so-called decision to cut time that mean I'm an obstetrician I determined that the patient needs an emergent cesarean section the time that I make that decision to this time that actually cut the patient should be 30 minutes or less this sounds like a long time and it is and if a baby is down with (Time 0:11:58)
- Emergency Sections in Obstetric Anesthesia
Summary:
I haven't done obstetric anesthesia for a few years so I think in general it makes sense that if you can do it under 10 minutes you're probably in pretty good shape yeah. For an urgency section to me urgent means you've got time to weigh your options and I would probably prefer to do a regional technique in that scenario. You have to have some kind of situational awareness to understand what is going on with the patient and the baby because these are emergent sections.
Transcript:
Speaker 2
section as a resident we induced and as we were intubating the patient they were splashing some some chlorhexidine onto the abdomen and cutting at the same time wow so that was truly emergent and then you know I think obviously you decide when you really have to to go you know as fast as humanly possible but I think as you're saying in general probably and certainly I haven't done obstetric anesthesia for a few years so I think in general it makes sense that if you can do it under 10 minutes you're probably in pretty good shape yeah and these emergency sections you try your best to to put a if you got an epidural in you try your best to dose it up and get a level that's dense enough and high enough to do an emergency sarian section but a lot of times we're just putting these people asleep yeah right okay so when you think about there's an emergent or an or an emergency section and what are you gonna do in terms of your anesthetic techniques so for an urgency section to me urgent means you've got time to weigh your options and I would probably prefer to do a regional technique in that scenario and you have to have some kind of situational awareness to understand what is going on with the patient and the baby because these (Time 0:15:56)
- What Are the Goals of Labor Analgesia?
Summary:
For an urgency section to me urgent means you've got time to weigh your options and I would probably prefer to do a regional technique in that scenario. You have to have some kind of situational awareness to understand what is going on with the patient and the baby because these situations can be very dynamic. In the labor and delivery suite we try to take away sensory pain while retaining as much motor function as possible to push out a baby so we could make a patient completely numb. For like I said for emergent to scissoring sections the goal is to get that baby out as soon as possible and general anesthesia is many times the quickest way to get that accomplished.
Transcript:
Speaker 1
so for an urgency section to me urgent means you've got time to weigh your options and I would probably prefer to do a regional technique in that scenario and you have to have some kind of situational awareness to understand what is going on with the patient and the baby because these situations can be very dynamic and so the ups the obstetric the obstetric staff should be pretty good about at least periodically if not continuously monitoring fetal heart rate while you're putting this regional Aztec technique in now again you have to have situational awareness so if your regional technique isn't going in very easily you can't be taken an hour or two to perseverate and try to get your spinal or epidural you just got to keep on moving and so for like I said for emergent to scissoring sections the goal is to get that baby out as soon as possible and general anesthesia is many times the quickest way to get that accomplished okay so let's talk in general what are the goals of labor analgesia what are you trying to do so let's talk yeah so let's let's contrast labor analgesia and surgical anesthesia okay so what we do out in the labor delivery deck is a lot different than what we do in the operating room so in the labor and delivery suite we try to take away sensory pain while retaining as much motor function as possible to push out a baby so we could make a patient completely numb (Time 0:17:04)
- Single Shot Spinal Failure Rates
Summary:
The failure rates is pretty good it's probably around 1 to 3% but some studies have quoted it as high as 17% now that particular center had trainees and people. The single shot spinal and repeat C sections are elective or sometimes we'll have a patient who's in labor who hasn't received a labor epidural. Their first aesthetic is going to be what we give them for a caesary section so we'll pop in a single shot spinal in the operator.
Transcript:
Speaker 1
okay so let's talk about a single shot spinal so when I think of a single shot spinal I think of putting a so-called smart mom of local aesthetic directly into where it needs to go the intrathecal space I am putting the needle exactly where the medicine is gonna work and thus we don't have to give that big of a dose we don't have to worry about where the dose is going this is the single shot spinal and repeat C sections are elective or sometimes we'll have a patient who's in labor who hasn't received a labor epidural and their first aesthetic is going to be what we give them for a caesary section so we'll pop in a single shot spinal in the operator now the failure rates is pretty good it's probably around 1 to 3% but some studies have quoted it as high as 17% now that particular center had trainees and people (Time 0:21:31)
- Do You Always Use the Same Dose for Every Patient?
Summary:
The majority of fail-spiles are due to operator error. Some patients who are gonna have spinal septums and they're gonna have congenital andromalies where you do injects mass in the intrathecal space just doesn't work. The dose once you get your needle in do you always use the same dose for every patient? Do you adjust it based on the patient characteristics how do you decide? Well you know I think that's how it's trained is as I remember it was everybody got 1.6 cc's of hyperbaric 0.75% bepivacane if they're really short you give a little less If they're really tall you give a
Transcript:
Speaker 1
younger years as an attending I would accept that less than smooth aspiration because I had the birefringence and some fluid coming back and I would inject and virtually every time I did that I would be disappointed and so my current practice is that I am very very very particular about making sure that I have smooth aspiration of fluid to confirm I'm in the intrathecal space. Okay that sounds good. That's not to say that you can you mean there are some patients who are gonna have spinal septums and they're gonna have congenital andromalies where you do injects mass in the intrathecal space just doesn't work. Sure. But I would say that the majority of fail-spiles are due to operator error.
Speaker 2
Okay and what about the dose once you get your needle in do you always use the same dose for every patient do you adjust it based on the patient characteristics how do you decide?
Speaker 1
Well you know I think that's how it's trained is as I remember it was everybody got 1.6 cc's of hyperbaric 0.75% bepivacane if they're really short you give a little less if they're really tall you give a little more and who knows exactly what that is (Time 0:23:52)
- Is There a Synergy Between Epinephrine and Fentanyl?
Summary:
I remember as a resident always being told that we could extend the length of the spinal by adding epinephrine maybe even by adding fentanyl or morphine. I think that those drugs do different things and if you give opioids that's going to add synergy to the block Fentanyl is short acting so you're gonna see the effects of fentanyl.
Transcript:
Speaker 1
okay now I remember as a resident always being told that we could extend the length of the spinal by adding epinephrine maybe even by adding fentanyl or morphine do you do that is that true that those extend the length of the spinal what do you think about that well I think that those drugs do different things so fentanyl and morphine are opioids and as you know in the spinal cord in the dorsal column there's the substantia substantia gel gelatinosa and if you give opioids that's going to add synergy to the block and it and it could extend the length of block it certainly is at the very least going to add to the quality of the block fentanyl is short acting so you're gonna see the effects of (Time 0:27:32)
- Epidural Use for C-Section
Summary:
Mike: I remember being taught that you then cannot go ahead and do a single shot spinal because there's a really high risk if you've already dosed up that epidural of getting a high spinal. In my my facility I have a basic algorithm for dealing with this exact problem so what I tell my residents and my fellow 10 colleagues is that when you have a patient with an existing laborepideral and you're gonna want to take them back for a C-section the first question you got asked yourself is is the epidural working or not working. If the epidural is working pretty well go ahead and dose it with a bunch of 2% lyocaine usually on the order
Transcript:
Speaker 2
on the situation that's great Mike I've actually I love that idea I've never heard of it but I think that's a fantastic and I would have probably saved me many times as a resident so let me ask you this is we're gonna talk about epidural use for C-section in a minute but let's say that you have a patient with an epidural you try to dose up the epidural to prepare them for the C-section and you don't get adequate coverage I remember being taught that you then cannot go ahead and do a single shot spinal because there's a really high risk if you've already dosed up that epidural of getting a high spinal is that true well so there's there's um there's interesting you say that because in my my facility I have a basic algorithm for dealing with this exact problem so what I tell my residents and my fellow 10 colleagues is that when you have a patient with an existing laborepideral and you're gonna want to go take them back for a C-section the first question you got asked yourself is is the epidural working or not working and if the epidural is working pretty well go ahead and dose it with a bunch of 2% lyocaine usually on the order of 10 to 20 CCs and divide doses (Time 0:32:03)
- Use Epidurals for C-Sections
Summary:
The challenge of activating an epidural for zeroing section is I like to think of a glass of cola so I've got this glass and for my labor analgesic I've filled it up half full with diet coke. It's difficult to get a block that's dense enough to get the patient comfortable when you've already used the epidural space to transmit dilute local aesthetic intended for labor analgesia.
Transcript:
Speaker 1
well first thing I would like to do is I want to see the level of the epidural and the the really the challenge of activating an epidural for zeroing section is I like to think of a glass of cola so I've got this glass and for my labor analgesic I've filled it up half full with diet coke and because for the labor analgesic I don't want a full anesthetic I just want kind of a white aesthetic so I give diet coke now with my half my glass half full of diet coke someone has decided that the patient needs to have a zeroing section now I have to fill up the rest the epidural space and try to make it as concentrated as possible and so I fill up the rest the epidural space the the glass with coke now if you add half a glass of coke to half a glass of diet coke what's going to result is something that doesn't taste exactly like coke but doesn't exactly taste like diet coke either and so it's difficult to get a block that's dense enough to get the patient comfortable when you've already used the epidural space to transmit dilute local aesthetic intended for labor analgesia okay so those are the theoretical concerns you're up against and doing that and (Time 0:35:48)
- Do You Ever Place an Epidural for a Spinal C-Section?
Summary:
When you're using the epidural space to provide your axial aesthetic you are relying on spread of local anesthetic by normal anatomy. There are some instances where it's better to do a slow steady ramp up of niraxial anesthesia like for instance if someone has auric stenosis which is a little bit rare in pregnancy but can happen with congenital lesions.
Transcript:
Speaker 1
in place rarely there are good reasons not to do it and there are some good reasons to do it so just to go back to the basics when you're using the epidural space to provide your axial aesthetic you are relying on spread of local anesthetic by normal anatomy you're hoping the patient has normal anatomy so that when you put your catheter in and inject local aesthetic it's going to uniformly spread around the dura across the dura to its intended site of action now when you do a spinal you obviate all those concerns by going directly to the mechanism of action the intrathecal space and injecting the medication right there but there are some instances where it's better to do a slow steady ramp up of of niraxial anesthesia like for instance if someone has a auric stenosis which is a little bit rare in pregnancy but it still can happen with some of the congenital lesions and so some of the iric stenosis can't have their cystic vascular resistance drop too quickly otherwise they're not going to have enough perfusion pressure for to perfuse vital organs and so some of the iric stenosis you can put an epidural in and really carefully slowly incrementally dose that epidural to get the desired level without the extreme sympathetic to me that's going to lead you to have problems the other thing the epidural can do is you (Time 0:37:50)
- The Bimole Distribution of C-Section Patients
Summary:
Residents particularly males is that when our epidural or spinal is failing for a c-section and they you know in good faith will suggest using ketamine. I'll ask them I'll say well if I was doing an open-app abduct to me on you and our spinal was wearing off would you want me to intubate you and give you cevo fluorine or do you want me just to give you slugs of ketamine? The answer is quite obvious, he says.
Transcript:
Speaker 1
young residents particularly males is that when our epidural or spinal is failing for a c-section and they you know in good faith will suggest using ketamine I'll ask them I'll say well if I was doing an open-app abduct to me on you and our spinal was wearing off would you want me to intubate you and give you cevo fluorine or do you want me just to give you slugs of ketamine and the answer is is quite obvious and so and so I really do see this this bimole distribution of people who are older who grew up putting people asleep regularly for c-sections who are completely comfortable doing so and then I see people who are 45 or younger who grew up in the era of avoiding generalize c-tiff or c-sections sometimes making irrational decisions and that's just my own personal observation from being a resident and being attending okay so how about the risk of general anesthesia should we is there should we be doing it a certain amount of the time should we avoid it no matter what what do we know about that well you're you're always going to have less complications with regional if the regional is done well and this all comes from the (Time 0:44:58)
- Video Laryngoscopes Have Made a Difference in Pregnancy and Delivery
Summary:
The primary consideration is to optimize oxygen delivery of the fetus. We typically will induce with propofol and succinylcholine and we don't use opioids. The nitrous oxide has a very low solubility in the blood and it's gonna wash off pretty quickly not so much the case for volatile.
Transcript:
Speaker 1
about so what you want to do is you want to your primary consideration is to optimize oxygen delivery of the fetus and so you're gonna want to put the patient a left larylle-acubus position there there is some conflicting recent evidence that says that might not be the best thing but for now it's what we got so you pre-accinate the patient as much as possible you want the surgeons prepped and draped right to cut so that there the amount of time that the fetus is exposed to general anesthesia is minimized we typically will induce with propofol and succinylcholine and we don't use opioids I mean you can use romefetinol live centers use romefetinol or trioblondis sympathetic response not a good idea to use fetinol because it will cross the placenta into the fetus and then after you secure the the area of the endotracheal tube you want to tell the obstetricians they can start cutting now prior to delivery you're gonna want to do about 0.5 mac volatile and 0.5 mac nitrous and the reason why we do this is we want to decrease the exposure of the fetus to the volatile aesthetic we know that the nitrous oxide has a very low solubility in the blood and it's gonna wash off pretty quickly not so much the case for volatile so our goals prior delivery are to decrease the exposure of the fetus the volatile now after delivery (Time 0:50:07)
- Preparing the Endotracheal Tube
Summary:
Use fetinol because it will cross the placenta into the fetus and then after you secure the the area of the endotracheal tube you want to tell the obstetricians they can start cutting now prior to delivery. You're gonna want to do about 0.5 mac volatile and 0.5Mac nitrous before delivering a baby. The reason why we do this is we want to decrease the exposure of the fetus to the volatile aesthetic.
Transcript:
Speaker 1
to use fetinol because it will cross the placenta into the fetus and then after you secure the the area of the endotracheal tube you want to tell the obstetricians they can start cutting now prior to delivery you're gonna want to do about 0.5 mac volatile and 0.5 mac nitrous and the reason why we do this is we want to decrease the exposure of the fetus to the volatile aesthetic we know that the nitrous oxide has a very low solubility in the blood and it's gonna wash off pretty quickly not so much the case for volatile so our goals prior delivery are to decrease the exposure of the fetus the volatile now after delivery we want to do the same thing 0.5 mac volatile 0.5 mac nitrous but for different reasons here instead of decreasing the exposure of the fetus to the volatile aesthetic we want to decrease the exposure of the uterus to the volatile aesthetic so after delivery of the fetus we want the ureus to clamp down and contract so that stops losing blood and the volatile aesthetic will inhibit that mechanism so what we do is we try to limit the volatile aesthetic so that the ureus can clamp down so you stop your post-partum average (Time 0:50:53)
- Preloading or Co-Loading?
Summary:
Phenylapcharin is now the first line agent and we use it when the heart rate is 60 or above. most to attenuate these from sympathetic the sympathetic to me but when you start looking at what's the evidence there really is any statistical significantly no statistical significant difference between preloading and co-loading.
Transcript:
Speaker 1
needed most to attenuate these from sympathetic the sympathetic to me but when you start looking at what's the evidence there really is any statistical significantly there's no statistical significant difference between preloading and co-loading so it really is kind of dealer's choice what you want to do now the the state one of the studies that I looked at that talked about no statistically significant difference between preloading and co-ling they advocated that instead you should use vasopressors so way way way back in the day and sheeps they showed that phenylapcharin caused urofosential insufficiency and so for a while way before I started to ask to use your phenylapcharin was not used because of this data a fedran was preferentially used but then a fedran was shown to cause fetal tachycardia and resultant acidosis and then in humans phenylapcharin was shown not to cause the urofosential insufficiency so phenylapcharin is now the first line agent and we use it when the heart rate is 60 or above when the heart rate gets below (Time 0:55:55)