Okay, so in this lecture we're going to talk about maternal cardiac arrest and its anesthesia considerations. My name is Tom Mangus. I do not have any disclosures, so I do not have any financial relationships or any commercial interest and I will not be discussing any off-label use during my presentation. Some learner objectives are, we would like during this presentation to discuss maternal mortality, review national statistics of maternal mortality, identify common causes of maternal arrest, discuss algorithmic approach to maternal resuscitation, and then finally discuss anesthesia's role during maternal cardiac arrest. So we need to first start by understanding maternal mortality and what the World Health Organization defines as maternal death. And ultimately the WHO defines maternal mortality as anything that is a death of a woman while pregnant or within 42 days of termination of pregnancy. Now this, the important thing to understand is that it's irrespective of duration and site of pregnancy and from any, this could be due to any cause related to or aggravated by pregnancy or its management. It's not from accidental or incidental causes. The National Center of Health Statistics also uses the WHO's definition of maternal death to determine the number of maternal deaths and usually the way that they categorize it is maternal deaths per 100,000 lives births. So this is going to be the statistic that when we start to look at some statistics is really focused on understanding what the level of maternal mortality really is. So when we look at our national maternal statistics, we can see I have three figures here and basically shows how maternal mortality has progressed over the last handful of years. Specifically looking at what the dates were, so to 2021 you can see that there was a rise in maternal mortality and that would have ultimately coincided with the COVID pandemic. Also we can see that from our slides that maternal mortality also can be categorized by race, specifically with our Hispanic population versus our white, black and Asian populations and you can see that there is some difference when it comes to racial disparity when it comes to maternal mortality. And then also understand that as our moms are getting older, the risk for maternal mortality begins to climb. Really the interesting thing when you start to look at maternal mortality, two-thirds of the US pregnancies that end in death usually occur in the postpartum period, especially within that first year and really it's not always within the first week, but it's in this seven to 365 day postpartum time frame demonstrating that not always is it the pregnancy that is the problem, it may be considerable the after response. So potentially postpartum depression and substance use will stick out as some of the reasons why maternal mortality occurs heavily in that postpartum time frame and we can see that this is a figure from a maternal mortality review committee of 36 US states, so a large portion of our states, 65% of the maternal mortality occurs during that postpartum time frame. And really some of the things within the first week is going to be bleeding, high blood pressure and infection, but as we start to get outside of that, then we start to see where there is the postpartum depression and honestly it's going to be not only substance abuse, but potentially cardiomyopathy induced by other things that the mom may be utilizing or just her underlying health conditions. So let's categorize these a little bit more when it comes to common causes. Mental health conditions can be seen in 23% of the time when it comes to our maternal mortality. Excessive bleeding, cardiogenic issues, 13% of those, infection, thrombotic events, cardiomyopathy and hypertensive disorders really are some of the leading causes, but we can start to see what really seems to be the high ranking causes, especially in that postpartum time frame would be mental health disorders. The good thing to kind of take away from this is that it's relatively uncommon, but the problem is that any mortality that is unexpected starts to question why it's happening and we really need to understand what is going on with our moms and we can start to see that when they come into the hospital. There's a higher incidence of that maternal mortality, especially when it comes to the mom had a presence of some type of comorbidity, especially if they came into the peripartum time frame with that comorbidity. And a kind of a staggering statistic when you look at cardiac arrest within the actual time frame of the hospital stay, that is even more uncommon and really when you look at it, the majority of cardiac arrest while they're in the hospital really comes from the DIC occurrence during that immediate post-delivery time frame. So as a result, there is a lot of prevention measures that have been put in place, specifically the California Maternal Quality Care Collaboration is one of those organizations that really heavily looks at why are we having this high rate of maternal mortality and ultimately what they defined was a tool that helped really look at early recognition of underlying issues, specifically looking at cardiac disease when they're in the hospital and knowing that we can have a high level of preventability when it comes to maternal mortality, especially if we understand the risk going into it. It's better to have an idea that the mom has a risk than to be caught behind the eight ball and now we are trying to catch up. So the CMQCC really has a good flow so when you go to see a patient, if you start to see that they are presenting more and more of these attributes, we need to really get higher levels of care involved earlier, that way we can have a plan set in place to help prevent poor outcomes down the road, specifically in that early to later postpartum time frame. There's also some algorithms when it comes to maternal arrest, specifically if we decide that we need to institute some type of lifesaving measure, the time frame to delivery and how we need to escalate that very quickly. So I have two graphs here for you guys to kind of look at, but these are going to be tools that can be utilized to help understand first the risk, but then also if we decide that the mom has, there's been this maternal arrest, what do we need to do? And early delivery is going to be one of those priorities in order to help give the patient some of the best results when it comes to cardiac function, knowing that immediately post-delivery there's a surge in that cardiac volume based on maternal physiology, understanding that we need to be able to support that maternal patient through that time frame and quick delivery is going to be one of those things. And really understanding that a perimortem C-section really needs to happen very, very quickly. Determining that we are in an arrest picture and then delivering within 5 to 10 minutes is definitely going to be one of those things that needs to be high on the triage and high on the intervention list is that we are in this, we need to deliver quickly. So some of the anesthetic managements when it comes to our maternal arrest is really trying to achieve quick return of circulation, knowing that not only is it good for maternal outcomes, but it's also good for fetal outcomes. So some things to really keep in mind is that having a system in place that allows rapid administration of not only BLS, but advanced cardiac life support, and then having it set in place that if we cannot get quick ROS, that we get to the operating room to deliver the baby as quickly as possible has been shown to have high level of being able to prevent maternal mortality. Some of the delivery benefits really ultimately is that when you're in this arrest timeframe, the maternal patient is going to be flat on their back. And we all know that having a gravid uterus laying on the venous return system definitely decreases the amount of volume that is able to return to the maternal heart, further compromising the ability to provide that basic life support on top of administering medications to circulate is going to be another very high level thing that needs to be done. So ultimately, can we give them some left uterine displacement during this timeframe that doesn't heavily to actually affect our ability to do compression? So there needs to be that understanding that we need to not only maintain the maternal circulation, but also fetal circulation and attempting to get ROS quickly is definitely going to be one of those things. Understanding that there's going to be severe volume restrictions based on a gravid uterus. And then not only that, but the fetal oxygen demand is going to be rising based on not receiving a steady flow. So, again, now you're going to start to have fetal compromise and ultimately advanced life or advanced airway support quickly to maintain that at least we're getting oxygen to our pulmonary beds. So whatever we're able to distribute via compressions does end up getting to our fetal circulation to help prevent further fetal compromise. And then really to understand that during that immediate postpartum timeframe, there can be that significant increase in cardiac output. So understanding that before a mom who is at risk that has high level comorbidities, having a system in place to either to monitor the cardiac output, having advanced invasive monitoring in place and ability to give large volume and give high levels of inotropic support may be necessary. So this is where that prevention aspect comes into play is understanding how compromised is the maternal heart prior to delivery will help guide some of the therapies so those therapies can be in place prior to delivery. So those therapies first are planned for and now that we actually have the patient in the hospital instituting those therapies prior to getting into a situation where we have a maternal poor outcome. So I do wanna kind of talk about a handful of these very high level things that will ultimately lead to maternal arrest. And first off, we have to talk about AFE. The issue with the AFE ultimately is that we don't really understand it very well. There's a lot of proposed mechanisms and through the years as we've started to kind of identify that this could be potentially a problem, we're not really sure really what is the ultimate cause. We, the currently the most accepted reason is that this is a massive systemic inflammatory response, almost what we would say like anaphylactoid and it's non-IgE mediated. And ultimately it's a reaction to our fetal, our maternal circulation being contaminated with fetal squamous cells. So when this was first being investigated, when during postpartum autopsies, fetal circulation, fetal cells were identified in the maternal circulation. So this is gonna be one of those things that really the current theory is that we ultimately have a massive systemic response based on these foreign cells being introduced into the maternal circulation. And then ultimately this degrades into a, almost into a coagulation picture where our moms will go into a DIC. But ultimately we're not really exactly sure what is the true cause of this. So, but some things to think about is really when we have a maternal arrest and we think it's an AFE potentially, we really have to diagnose by exclusion, knowing that there are some risk factors, but they're not always firm in the way that they present. But some that have been identified during literature really has to be due to maternal age, multi-parity abdominal trauma, cesarean section, induction of labor. So at my facility, we do a lot of induction of labor and that has been seen to be linked to AFEs, placenta previa, eclampsia, and then eclampsia, multiple pregnancies, and then really, is there some type of disruption in the uterus and cervix and then early separation? But again, the data is not 100% in that it's very limited and there's a lot of just theory type speculation because we just don't have a great understanding. So really, we have to start to look at really the symptoms and are we excluding other causes before we decide that we are having an AFE type presentation? So some things to think about when it comes to like some signs and symptoms, it is usually very, the symptoms are usually very in a sudden onset type manner, meaning that all of a sudden we have a maternal patient who just abruptly just goes down and we don't exactly know why. But really, when you think about it, it's gonna be hypotension, it's gonna be one of the most common signs of an AFE. Other signs include pulmonary compromise, so acute dyspnea, coughing, cyanosis, fetal bradycardia, and then some other maternal signs would be a altered mental status or encephalopathy and pulmonary hypertension and coagulopathy. But again, these, as we know, are really signs of a lot of things that are happening, things like pulmonary embolism, air embolism, acute MI, septic shock, cardiomyopathy, anaphylactic shock, high spinal, so things that we have done to the patient, given them a neuraxial that has caused this, and then other obstetric complications like placenta abruption, eclampsia, uterine rupture, and peripartum hemorrhage are all very, present in similar ways, so we really need to rule out the box that's in the blue prior to really assuming that if nothing else is going on, then maybe it is an AFE. So, some things to think about when it comes to AFE management is that there are no real consensus guidelines when it comes to really preventing it, so it's really a supportive type nature of an event, so really what we need to consider is that the symptoms that we see, we need to treat it in that manner, is that we just need to do symptom management because ultimately supportive care is gonna be the best thing for this patient at the time, so if they're hypoxic, addressing their hypoxia, if they're hemodynamically compromised, addressing their hemodynamic status, and in order to do a lot of these things, we need to have extra access, we need to be putting in invasive monitoring lines, and then really understanding that because of the symptoms and because of the SIRS response, these moms do have a tendency to start to have a DIC type picture, so really understanding what is going on with their coagulation status is gonna be very high level at this point, so really assessing your coagulation status, so if you have access to a RapidTag, this would be the time to be sending sero RapidTags and treating the patient based off of what is being presented currently. Some other things to really think about is that potentially a benefit would be assessing that coagulation is understanding is what is the response to heparin, and knowing that heparin with these patients probably will ultimately make it worse, but we're not exactly sure because that again is very split. If some sources saying initiating anticoagulation is a good thing, other sources do not say, so it's really a hit or miss when it comes to literature because again, the understanding of this process is not well defined. I do give you a little bit of a breakdown chart that has been proposed from the Society of Maternal and Fetal Medicine, really looking at if we suspect we've excluded other things and we've suspected that it's an AFE, and especially if they've arrested initiating CPR and then deciding do we need to deliver, and then doing some other interventions, specifically maintaining cardiac support, avoiding overloading with volume, knowing that during this delivery timeframe there is gonna be an excessive volume shift, which is just normal maternal physiology, and understanding that if the mom has had a cardiac compromise, and now they have further cardiac compromise in initiating some type of inotropic support, things like Levifed have been shown to be really something to help address that sudden hypotension that we talked about, and then understanding that really do we need to add other inotropes to address the other cardiac, the further cardiac compromise, things like Dibutamine and Mironone, and then really the focus at this point is maintaining cardiac function, maintaining forward flow ultimately, and some case studies also identified using things like Nitric to help decrease afterload really helped and decrease also the pulmonary vascular resistance have demonstrated some benefits, but again there's no real solid phase, and then understanding that while the right side starts to fail, the left side will ultimately fail, and coagulopathy does usually follow along with as we go down this path of this increasing surge response. Now interestingly there is a protocol that is very split in literature about if it is good, if it's not good, and that's called the AOK protocol, and basically what that means is AOK is an acronym for the three things that have been shown to have some benefit, but again is not 100% literally sound from looking at research on AFV, but it's going to be utilization of Atropine on Danzatron and Ketorolac in that Atropine being about a milligram dose, a Danzatron being an eight milligram dose, and Ketorolac being a 30 milligram dose. Ultimately the proposed mechanism of action for this AOK is really reducing the pulmonary vascular resistance knowing that as we start to have this hypotensive hypoxic picture, and a surge response, we start to have a very high spike in our pulmonary vascular resistance, giving things that first can help support our cardiac function, Atropine being one of those things, dosing something to the extent of Danzatron which helps address serotonin changes which seems to help affect our platelet function, and then again giving things like Ketorolac helping to start that potentially that anticoagulation cascade trying to prevent the utilizations of our products too early throwing that which would ultimately lead to the maternal patient going into DIC. Again, it's very split, but from what literature says and some case studies have said is that it is beneficial. So in the grand scheme of things, while we can't say that this is gonna be the end all be all, it doesn't hurt potentially utilizing this in the setting of what we think might be an AFE. Again, knowing that the goal is to prevent the mom going into DIC and then preventing or trying to mitigate the surge response and mitigate the cardiac compromise knowing that Atropine can be one of those things and on Danzatron having a serotonin response can be a response also. So is this something that national organizations are gonna support? The answer is gonna be no, but know that there is some growing literature around it, but ultimately because FCEs are so poorly understood the actual implementation of it or the firm recommendation of it, it can't be done at this time. But this is something that we want you to be aware of that there is things in literature that do address it. It's just, it's not a hundred percent able to be recommended at this time. So these are my references and I thank you for your time and I look forward to seeing you guys in person.

maternal cardiac arrest

anesthesia considerations

maternal mortality

perimortem C-sections

amniotic fluid embolism

AOK protocol