Transcript
Speaker: Welcome to Critical Matters, a sound podcast covering a broad range of topics related to the practice of intensive care medicine.
Speaker: Sound provides comprehensive critical care programs to hospitals across the country.
Speaker: To learn more about our programs and career opportunities, visit www.soundphysicians.com.
Speaker: And now, your host, Dr. Sergio Zanotti.
Speaker: Patients with disorders of consciousness are common in the ICU.
Speaker: Every intensivist, regardless of the type of ICU they work in, will encounter this clinical problem on a regular basis.
Speaker: In today's episode of the podcast, we will discuss the evaluation and management of acute disorders of consciousness.
Speaker: Our guest is Dr. Cheryl Lee Chang, a practicing neurointensivist, a professor of neurology and a division chief of neurocritical care in the Department of Neurology at Duke University in Durham, North Carolina.
Speaker: Cheryl, welcome to Critical Matters.
Speaker: Great.
Speaker: Thank you so much for having me, Sergio.
Speaker: I appreciate that.
Speaker: And as you were discussing prior to recording, this is a very common and broad topic, yet quite relevant.
Speaker: So maybe I'll start with a question of why do you think this is an important topic for the intensivist at the bedside?
Speaker: Well, this is, as is discussed in the paper we recently wrote, and I think people see it in the literature all the time and at the bedside, it's a common thing that we address that we see that people have this change in their mental status and really don't know how to address it or easily attribute it to something without really thinking through it in a very systematic way.
Speaker: And I think you can miss very important signs by not paying attention to it.
Speaker: So we thought that this might
Speaker: be a very relevant topic to teach people a very simple way of kind of thinking through something that we see so commonly.
Speaker: Absolutely.
Speaker: And I think that as we were discussing,
Speaker: It's a broad topic.
Speaker: It may be not as sexy as some of the other topics that get published on a weekly or monthly basis in major journals.
Speaker: However, I would submit that any of our listeners today, they were to the ICU, they'll encounter plenty of clinical problems that we're going to describe today.
Speaker: Exactly.
Speaker: And it started also with a lot of interest in delirium and anxiety.
Speaker: One of the things that I think is very relevant is that people recognize that we're researching delirium in the critical care world, that also neurology also talks about acute encephalopathy.
Speaker: And so one of the things to talk about is in 2020, they came up with an updated nomenclature of 10 societies, including the Society of Critical Care Medicine and various world-based neurology programs.
Speaker: societies and geriatric medicine, anesthesia, to really talk about the fact that acute encephalopathy is really that pathobiologic process that underpins the changes that we see in the patient's level of consciousness.
Speaker: So delirium, coma is a continuum that results as acute encephalopathy.
Speaker: And being aware of that and figuring out the cause of that acute encephalopathy that causes a delirium or coma is really an important aspect of our general critical care.
Speaker: And I think you mentioned nomenclature, and it's very important to call things by the right name, so we're all talking about the same thing.
Speaker: And obviously, terms like delirium, acute encephalopathy, and coma are commonly utilized in our daily clinical practice.
Speaker: And sometimes they might mean different things to different people, and that's why understanding what the concise definitions are is important.
Speaker: How would you define acute disorders of consciousness?
Speaker: So acute has been defined now as something that is over a short period of time.
Speaker: So the delirium, well, let me start first.
Speaker: Delirium, let's start with that.
Speaker: And coma is the extreme of delirium, is results from acute encephalopathy, which is considered a disturbance in attention or awareness that develops in a short period of time, usually hours to a few days, and it causes disturbance in cognition.
Speaker: So as the article also refers to, and some people wonder about why we talked about the acute disorders of consciousness being less than four weeks.
Speaker: That is a definition that this 10 Society group decided to look at.
Speaker: There are obviously more chronic or subacute disturbances that need to be evaluated, but the acute delirium coming from an acute encephalopathy is what we really address in the paper.
Speaker: Perfect.
Speaker: Let's talk a little bit about the epidemiology and then jump into etiology.
Speaker: And what can you tell us about the epidemiology of acute disorders of consciousness in adult patients in the ICU?
Speaker: Well, in looking at different studies and, of course, different cohorts,
Speaker: it can be seen quite frequently, but more recently in looking at patients with COVID-19, it was seen in nearly 33% of critically ill patients.
Speaker: Now we know in the ICU that oftentimes we're sedating patients, you know, intentionally to ventilate them adequately or other procedural, and sometimes they don't arouse to the state that they were previously.
Speaker: We need to look at that.
Speaker: We often assume that it's the medication, but again, there could be changes as well.
Speaker: So again, the percentage varies depending on the cohort.
Speaker: But again, looking at our acute patients that were coming in at the time just a couple of years ago was quite high, nearly a third of our patients that had unknown causes for changes in consciousness, levels of consciousness.
Speaker: And I think that, like you mentioned in the critical care paper, which we will reference in the show notes with a link, it's been difficult to ascertain the exact etiology, but during COVID-19,
Speaker: We had very good information suggesting that 30 plus percent of patients were comatose for many reasons.
Speaker: But ultimately, what it really means is that it is very likely that in any ICU in the United States, you have these patients right now today, a common occurrence on our daily practice.
Speaker: Correct.
Speaker: One of the things that I really took as a great tool from the review paper was the framework you present for understanding the different etiologies, and maybe for them, I mean, further discussing evaluation, diagnosis, and treatment.
Speaker: Could you just walk us through that framework?
Speaker: Right.
Speaker: So when we're thinking, you're standing at the bedside, I think obviously we think about going through the history, trying to figure out through our sleuth work of the history of how this progressed or if this predated what happened when the patient got to the hospital.
Speaker: So whether it be our medications or other things.
Speaker: And that starts our structural thought of, you know, is there structural, is there functional?
Speaker: and kind of working through in an order of acuity of what you can also treat.
Speaker: So when we think about the reason to think about structural is because we always think about imaging, but when we're thinking about, oh, let's just get a CT, you have to think about what am I going to find with the CT scan?
Speaker: an acute ischemic stroke you're not going to find that hopefully on the CT scan because if you caught it early enough you might be able to treat it but the history, the physical with the examination is going to lead you into the workup that you're doing.
Speaker: Going to the bedside, getting a history, doing a neurologic exam, looking for focality, some focal changes is going to direct your workup in what imaging you're going to get.
Speaker: The CT scan is usually the first thing we get and easiest to get because the MRI, obviously, we need to find out more background of whether it's safe to do.
Speaker: then the workup that you're doing, people are, you know, we shotgun laboratories, but your examination may cue you into the fact that this patient may have endocarditis because you hear a murmur or you see Janeway lesions or oscer nodes or things like that.
Speaker: So the exam will help you decide whether you might be getting blood cultures in addition to tox screen and other laboratories so that it'll work
Speaker: Again, you're thinking about your workup in a very systematic fashion.
Speaker: Also looking at your exam, you may see funny movements, which may make you think the patient's seizing, or of course, you know, papilledema, where you're thinking about, you know, not only with the imaging, but do I need to treat that patient to prevent them from herniating and the rest of the laboratories.
Speaker: And then, of course, your examination with the
Speaker: looking for when you might have a temperature, do you need to think, and we're also the exam with nuchal rigidity, or do you need to think about an infectious etiology as well?
Speaker: Remember the history is giving you something about that as well.
Speaker: Has the patient traveled?
Speaker: Have they been having a headache?
Speaker: All those things can again lead you down this pathway.
Speaker: Inflammation typically is there's a longer history of something going on and again stroke can show it as a vasculitis so that might be something a little bit further down the line.
Speaker: And then pharmacologic of course again back to the history, back to thinking about getting a tox screen for laboratories and or whether the change in the level of consciousness this disorder happened.
Speaker: after the patient has been, say, in the ICU for a period of time.
Speaker: Is it something we've done or something we've stopped when the patient came in, say, for their bad pneumonia and we stopped one of their SSRIs that may be important to that patient?
Speaker: So I think that going through this in a systematic way of
Speaker: Is it structural?
Speaker: Do I need to fix it?
Speaker: Is it metabolic or functional?
Speaker: Is it infectious, inflammatory, and pharmacologic?
Speaker: It really gives you a way of thinking about the shotgun approach to a patient with disordered consciousness.
Speaker: And I think that what you mentioned, obviously, this is a very intentional decision you made with the structure, with the framework, is that you've kind of
Speaker: line them up in terms of time sensitive, right?
Speaker: So structural, if you miss the boat there, you might lose a window of opportunity for treatment, same with functional.
Speaker: And then as you go down infectious, inflammatory, pharmacological, you probably have a little bit more time to figure out what needs to be done and perhaps being certain of what's going on is more important there.
Speaker: Any other comments in terms of how people should think about this?
Speaker: I think the key is the most frustrating thing is when you see that someone wrote in their history and physical, you know, non-focal.
Speaker: To me, that means that they really didn't do an exam that can tell you if they've actually looked at the
Speaker: you know, the cranial nerves, do they look at the pupils?
Speaker: Do they see if the patient can move their eyes?
Speaker: Do they look at a facial drip?
Speaker: Do they see if, I mean, it doesn't have to be long.
Speaker: It takes a minute or two minutes to maybe go through an exam, but especially in someone that has a disorders of consciousness, it makes it a very fast examination typically to go through cranial, you know, mental status, the cranial nerves, the motor exam, see if there's any, uh,
Speaker: difference in strength and or whether it's it's peripheral problem such as Guillain-Barre or a condition that seems to have folk they say focality but I think that it's important to say what you've looked at because that is key in the neurologic exam for that disorders of consciousness but it helps focus your your workup as well
Speaker: And same with the general exam, that the general exam, I think people are much better at documenting that than when they're approaching a patient with the disorders of consciousness or neurologic exam.
Speaker: And I think this is an important point that might be worth digging a little bit deeper.
Speaker: And Cheryl, you're trained in neurology and medicine and neurocritical care and medical, let's call it a critical care.
Speaker: So,
Speaker: you've seen things from both sides, but your clinical practice, I understand, is mostly in the neurocritical care world today.
Speaker: So you sometimes might get called in consultations and see this that you're expressing as a frustration.
Speaker: But the truth is, from my perspective as an internist, I feel that there's two areas that we need to get better at, and I want your thoughts.
Speaker: One is...
Speaker: Like you said, the physical exam, I mean, unfortunately, the physical exam has been undervalued, I think, lately.
Speaker: And there are parts of the physical exam that might be less helpful.
Speaker: But when it's related to these patients, being precise and being, like you said, complete can be done in an efficient way.
Speaker: And it does provide invaluable information.
Speaker: So I want some comments on that.
Speaker: And the second part is...
Speaker: using objective grades such as GCS or NIH stroke scale, four score appropriately, so that the fidelity of what I'm relaying to you as a consultant is there, right?
Speaker: I mean, are we talking about the same things?
Speaker: And I think that this is something that often, I think, unfortunately, contributes to not ideal care.
Speaker: That's an excellent point that often we think of those tools as something used in research, but it does give us
Speaker: And initially were developed to talk about also what is a change.
Speaker: I mean, although it was an objective tool for research, it also is an objective tool for helping our nursing team communicate to us when there's a change in a patient's examination.
Speaker: That's what the NIH Stroke Scale has been, that zero is normal.
Speaker: And for any neurologic change in the different systems, you get a point, additional point.
Speaker: So when we see a patient who's in the ICU who's changed from, say, 8 to suddenly a 12 or 14, that means that something needs to be evaluated very rapidly.
Speaker: It's within the inter-rater reliability issue.
Speaker: So we use that.
Speaker: Same with GCS when there's a drop, of course.
Speaker: There are typically protocols for nursing to communicate information.
Speaker: At the same time, when we're speaking to our colleagues, giving handoff or trying to get a consult, I think, like you said, that ability to explain in a very succinct manner, you know, the situation of what the change was rather than, you know, I want you to come see this patient or it's really much more helpful to understand what the impact.
Speaker: I guess the severity of change or the depth of change and having the same, being able to go back in a chart and review that chart and understand what somebody was seeing before often is lost in the, you know, we're often, you know, deaf by EHR, but we also need to make sure our piece, especially in examinations, especially in there.
Speaker: A lot of times people are using cut and paste, which is unfortunate too, that they,
Speaker: There are times where you see that something that couldn't possibly have been the case from looking at the nursing notes as reflected in the charting by our providers, you know, physicians and others is not always accurate or could not have been accurate.
Speaker: Perfect.
Speaker: And with regards to the exam, I don't have a lot of experience with the pipillometers, but I'm hearing more and more about that.
Speaker: And obviously, the eye has always been kind of a very particular window into the neuro exam.
Speaker: And we've lost the ability to look for papilledema.
Speaker: People, I mean, do a very sloppy exam with pupils description.
Speaker: Any comments there in terms of how that can be helpful?
Speaker: Yeah, so I'm a little bit of a hair tech because I definitely see the value of it, and we use it all the time, and I advocate for that in our patients that we're looking for these subtle changes.
Speaker: And so the pupilometer, for those who aren't very familiar with it, is an automatic way of looking at the pupils that take in the size of the pupils at start and whether there's antisicoriae.
Speaker: They look at the constriction velocity, so how fast it changes to get smaller, as well as the amount, the percent change, and puts it all into an algorithm and spits out a number called a neurologic pupillary index.
Speaker: And that number drops from a more normal number of four to less than three when, say, there's evidence of increased endocrinical pressure that there's maybe lower
Speaker: uncoherniation going on or something that's happening that's changing that third nerve velocity, or the third nerve and the velocity of the constriction of the pupil.
Speaker: So it can be extremely helpful when you're trying, you don't have an ICP monitor and you have a patient say with a large intracerebral hemorrhage or someone that you're worried about for other reasons of having increased endocrinial pressure.
Speaker: But one thing that
Speaker: when I said heretic that people cannot forget that just a flashlight can be helpful.
Speaker: I did have one resident once come up to me and say that the patient had a change and I said, so what was the pupil's size?
Speaker: And he said to me, well, I didn't have one of those funny machines.
Speaker: People forget that they could actually, you know, use the ambient light to look at the pupils if they don't have a flashlight or find a flashlight.
Speaker: You don't always have to have the most advanced, updated, you know, technology to be able to look at a simple thing.
Speaker: But it can be very helpful, especially the value of technology.
Speaker: I tell people in a neural ICU that the neural nurse is the most important person in that ICU, that we have oxygen monitors for the lungs, we have telemetry, cardiac monitoring for the heart, but the only real monitor we have for the neurologic change is our well-trained neural ICU nurse.
Speaker: And so the pupilometer is a tool that helps augment their population
Speaker: their expertise in the ICU and helps give us some objective measure of change as well.
Speaker: So very helpful, just as when they do a GCS or an NIH or just a general neurologic exam, these are all really important for us to follow.
Speaker: Absolutely.
Speaker: And I believe the other aspect that's very important about this discussion of serial exams, objective scores, is that disorders of consciousness in adult patients is a very dynamic process.
Speaker: And this is true for all neuroemergencies.
Speaker: And these changes that can be measured are usually indicative of complications or worsening status that might require a different approach from a therapeutic standpoint.
Speaker: Exactly.
Speaker: I think the ability to follow and follow it objectively is a key element of how we're able to enact or make changes for that patient.
Speaker: Before we... Sorry.
Speaker: Absolutely.
Speaker: Sorry about that.
Speaker: No.
Speaker: Before we jump into a little bit more details on the evaluation of different types, you did mention in this framework of structural, functional, infectious, and inflammatory and pharmacological some examples.
Speaker: But I wanted to just ask you from an etiology if you can just give us a quick blurb or reminder of some of these that might not be as common for a general intensivist.
Speaker: So in the structural category, obviously stroke, intracerebral hemorrhage, sub-argonate hemorrhage are things that we see on a regular basis or hear about.
Speaker: But there's some that might require a little bit more of an index of suspicion, such as cerebral vein thrombosis.
Speaker: Any comments of what we should suspect there?
Speaker: Yeah, so that's something that
Speaker: Well, classically, we would see it in patients who were dehydrated.
Speaker: Patients also, pregnant women, are also a higher risk factor for that.
Speaker: The classic symptoms are someone who has headache with that decreased level of consciousness, then seizures.
Speaker: And when you get a scan, you'll see mostly that it will have, well, a
Speaker: venous infarcts so you may see areas of hypodensity but also you may see areas of hemorrhage and it's key to recognize this because when you look at it and you see a hemorrhage you think wow i would never anticoagulate yet on the the guidelines have looked at all the literature and show that when you have a cerebral vein thrombosis
Speaker: These are patients you absolutely need to anticoagulate because otherwise they are less likely to survive.
Speaker: So it's important to think about it.
Speaker: But classically, someone who's hypercoagulable or, as we mentioned, dehydration pregnant, and think about it when you see a scan, you see hypodensities associated with hemorrhage.
Speaker: And the way to make the diagnosis is getting a CT venous phase,
Speaker: or MR with the venous phase.
Speaker: Perfect.
Speaker: And in the functional category, I mean, obviously, extreme temperature being in Texas in the summer, I mean, we've had a huge heat wave.
Speaker: I'm sure some people have presented to the ICU with heat strokes throughout the state.
Speaker: But there's others that are very common, such as electrolyte problems, metabolic problems.
Speaker: But the one I wanted to ask you about, which is kind of a syndrome that has evolved over the last couple of years and keeps expanding its causes, is the PRESS syndrome.
Speaker: It used to be something we only thought of, hypertensive emergencies, but there seems to be more to that.
Speaker: And that might be something that maybe we don't get the right imaging people kind of miss.
Speaker: Any comments on that, Cheryl?
Speaker: Yes, I think we see it, and, you know, a classic is with seeing it with tacrolimus or some of the other medications that are used for immune modulation.
Speaker: It can be seen as well as that hypertensive patient.
Speaker: And it's typically, and they don't quite understand why it's,
Speaker: It is, and it's called posterior reversible because it usually shows up at the occipital lobes.
Speaker: People will present with headaches, seizures, again, change in level of consciousness.
Speaker: And then the classic finding, best seen, you may see it on CT scan if the edema is well-developed posteriorly, but the MR and with the flare signal is, again, probably the best way to see it.
Speaker: And it's something that needs to be suspected.
Speaker: There's not a lot you can do about it except remove the offending agent, if it is an agent, or control the blood pressure and then treat the patient, mostly medical management of just watching for increased intracranial pressure and supporting that patient.
Speaker: Perfect.
Speaker: So we mentioned that as your initial evaluation, obviously, it would start with history and physical exam and lab profiles.
Speaker: Like you said, the non-contrast brain CT is commonly utilized, probably overutilized in some cases, but in these patients with altered mental status or with any disorder of their consciousness, I think it's the to-go imaging test and some other exams that might be done depending on the state of the patient, such as portable X-ray and POCUS.
Speaker: But let's talk a little bit about, as we go through that framework, what are a little bit more directed testing that you might need for these patients and how you would approach it?
Speaker: And maybe we can start with a structural.
Speaker: I guess that the first question you have in the CAT scan is, is there blood, no blood?
Speaker: Is there a structural abnormality or not?
Speaker: And how would you proceed from there if you're thinking this could be a stroke?
Speaker: Right.
Speaker: So if there's a, if the patient has focal findings or even sometimes it's a basilar, it may be a basilar thrombosis.
Speaker: So you're looking for, you know, one side versus another, but the patient may present mostly with a decreased mental status, but that's why cranial nerves are important to look at.
Speaker: So it is important to think about when you see nothing on the scan and there's no hemorrhage, is it still a stroke?
Speaker: And to then,
Speaker: The classic would be for the stroke, and most people have stroke teams, but we would be talking about going to a CT angio in that case, if we're thinking about a stroke and considering even perfusion studies to see if we would address this either with TPA.
Speaker: And in that case, there's a
Speaker: And I don't want to get into the details of all the stroke care, but now with the wake-up stroke in patients, we can sometimes, when they wake up, we don't know the time of onset, get an MRI, and there's no evidence of a flare change, meaning edema with dying brain, and there's only evidence of maybe a small stroke on the DWI we can give TPA.
Speaker: But otherwise, we might think about getting our endovascular team.
Speaker: Otherwise, we're going to more advanced imaging.
Speaker: If we're out of the realm of stroke, we're thinking about getting an MRI at that point and potentially an MRI to look at the vasculature.
Speaker: And when we see nothing there or something that seems unrelated, then we would be thinking about functional category.
Speaker: And this is
Speaker: Again, going on sometimes concomitantly, and some people say, well, I don't want to delay.
Speaker: I'm worried about other things.
Speaker: Of course, you'd be sending off laboratories thinking about, again, whether you need to get in, say, an EEG on that patient.
Speaker: Look for non-convulsive status epilepticus, which is one of the, what we call a functional category.
Speaker: Okay.
Speaker: I don't know if that's the focus you wanted me to take, but also on the CT scan, when you're looking at the CT scan and there's no hemorrhage, we also be thinking about edema, whether there might be something else like you talked about, where you might see something very subtle, like the posterior changes, the press, whether you might see
Speaker: something else that would lead you into thinking about some other small petechiae that may or what looks like petechiae or small punctate hemorrhages that may think make you think well maybe there was trauma that went on that you're not sure about maybe this is diffuse sexual injury so the imaging and looking at it yourself and not just and I think an important part sometimes
Speaker: is trying to understand a little bit of the details of what the radiologist might be reading.
Speaker: But just like you might look at your chest X-ray or should be looking at your chest X-ray yourself, I think looking at the understanding some of the basics of a general CT scan is sometimes really helpful as well, looking for shift.
Speaker: But the concomitant workup would include thinking about getting your tox screen in the different laboratories and moving on from there.
Speaker: Sergio, is that what you were driving at?
Speaker: Absolutely.
Speaker: And I think you touched on something that I wanted to dig a little bit more on, which is EEGs and non-convulsive status.
Speaker: So obviously in a neuro ICU where you're doing a lot of EEGs, you're probably finding a lot of non-convulsive status.
Speaker: But if you're not looking for it,
Speaker: you're never going to find it, right?
Speaker: So how should we think about this outside of a neuro ICU?
Speaker: When should we look for it?
Speaker: And then I also see a lot of discussion or promotion of the commercial EEGs that are easier to use, that are not full channel EEGs.
Speaker: How do those play into this story of non-convulsive status?
Speaker: So starting with your question about not being in the neuro ICU, there's an excellent article by Odo that shows that the rate of non-convulsive status is quite high in the septic patient.
Speaker: And in the general ICU, we see a lot of patients with sepsis.
Speaker: And we think that they have a septic encephalopathy and don't think about are they actually, could they actually be seizing?
Speaker: So I challenge people to actually start putting a non, you know, putting, thinking about non-convulsive status, putting an EEG even on their septic patients that have a impaired level of consciousness.
Speaker: because you may detect something that can when we know that non-convulsive status can cause brain injury, so it needs to be treated.
Speaker: So don't think that because you're not working with a patient with a tumor or an intracerebral hemorrhage or a known lesion in their head that they might not have non-convulsive status.
Speaker: When a lot of times we do get called from other hospitals saying, well, you know, we don't have a continuous EEG, we don't have epilepsy team here.
Speaker: There is, as you mentioned, these now more limited array EEGs that have been shown to have the ability to pick up not subtle changes or nuances on the EEG, but to
Speaker: status epilepticus, something that's generalized.
Speaker: There's good literature to support the use of these.
Speaker: They're called hairline arrays or limited arrays.
Speaker: They can be read by the team that's in the hospital.
Speaker: So say it's a hospital that doesn't have 24-7 coverage with a neurologist, has other neurologists that come in every so often, but not a 24-7 team.
Speaker: So it could either be using that team who doesn't want to typically be there 24-7 or read EEGs 24-7 or a service that's offered
Speaker: through the company that has a limited array that the hospital can contract independently with.
Speaker: I believe that's how it works.
Speaker: I'm not sure.
Speaker: It's called a subscription model where this technology is put in place and then the hospital decides how they want to have the reads be done, whether their own team or another team would be utilized.
Speaker: So it can be very helpful in sites that
Speaker: have a reasonably robust ICU but may not have the full 24-7 EEG coverage that's necessary to detect this because it is an important pathologic state that can be, that worsens outcome in patients.
Speaker: Perfect.
Speaker: Cheryl, the last question I want to ask you about evaluation before we move on to treatment is, again, something that is not new or fancy, but I think is often underutilized, which is the lumbar puncture.
Speaker: What will you tell our intensivist, or when should we get a lumbar puncture?
Speaker: I think we're determining more frequently that
Speaker: patients who have a little bit more prolonged typically, and maybe we should be picking up sooner, but often it's a prolonged change in their psychological state that the family's thinking, well, they're acting kind of odd.
Speaker: And actually some of these patients end up going to the psychiatric ward and end up coming to acute critical care by seizing, going to, you know, with potentially status epilepticus or
Speaker: That's the classic way that they get to the ICU.
Speaker: But there is an inflammatory process that could be either perineoplastic or an immune-mediated, non-infectious process.
Speaker: encephalitis.
Speaker: And so that needs to be thought about in addition to the one that we always think about, of course, the patient with the stiff neck, the patient with fevers, white count, where we think, well, you know, and potentially exposure history, where you think about getting an NLP.
Speaker: So what we're thinking about in the classic one, of course, with the fevers and the stiff neck or the bacterial meningitis, but viral meningitis with
Speaker: not only the atypical rickettsial or other type of diseases, and also HSV, which will show up on the MRI as well as medial temporal changes.
Speaker: We're finding that it's quite frequent that we're picking up a cause that is due to a perineoplastic process, potentially, or from a channel of
Speaker: antibody that's occurring.
Speaker: So it's something that I think we, as they've looked at it further, and Dalmo had done most of this work in the antibody mediated encephalitis, that it's more common than infectious encephalitis.
Speaker: So there's an autoimmune encephalitis alliance clinicians network that has looked at this and found that the estimated prevalence rate is higher with this autoimmune encephalitis.
Speaker: than even infectious.
Speaker: So it needs to be thought about when patients have, and it can affect these antibodies to either the intracellular or surface antigens of the neurologic system can be in different places.
Speaker: So it can be limbic where we get these patients with the
Speaker: change in their mental status, their psychological state, or their psychiatric state, in addition to those that have seizures and brainstem and even cerebellar findings.
Speaker: It can affect very
Speaker: very varied areas.
Speaker: So it's important to think about.
Speaker: And the treatment is typically after a workup, which usually includes an MRI where you may see these diffuse changes and an EEG looking for seizure and the LP would be thinking about also looking for perineoplastic causes.
Speaker: So looking at a chest CT, abdomen and pelvis.
Speaker: And then
Speaker: When you're also sending that LP, it needs to go to a laboratory.
Speaker: Typically, it's Mayo.
Speaker: That's the laboratory, I think, nationally that most are sending it to and that does this nationally for us, but blood needs to be sent as well.
Speaker: And then we have to think about the immune treatment.
Speaker: Typically, steroids might be the first way we go, then either IVIG or plasma exchange.
Speaker: So it's important to think about
Speaker: Those who write about it talk about the fact that there are probably many people in the psychiatric wards who had an autoimmune encephalitis and probably so burnt out at this point that there's nothing that can be done, but should be thought about when people have a very rapid and odd change in their mental status.
Speaker: So it's psychiatric status.
Speaker: So something to think about.
Speaker: Perfect.
Speaker: Let's talk a little bit about treatment.
Speaker: And obviously, there is a group of interventions that are common rescue therapy interventions for all patients who present with acute disorders of consciousness that are important for the ICU.
Speaker: So maybe we could start with those or ABCs of what you would consider as a neurointensivist when you're seeing these patients initially.
Speaker: So elaborate a little bit more because it depends on
Speaker: when you're, what you're seeing and what you're treating.
Speaker: Fair.
Speaker: I was thinking of what are the considerations you would have for airway management and hemodynamic management in the critical ill patients that present with altered mental status or disorders of consciousness?
Speaker: Yeah, the basics, right?
Speaker: So what you're talking about is thinking about making sure, and with
Speaker: With an altered mental status, we typically use that GCS of eight to intubate.
Speaker: Not always necessary.
Speaker: If you know that this is something that's transient, like a patient who has a seizure, sometimes you could put them in a rescue position and stop the seizure and wake them up.
Speaker: We see this often where a patient comes in from the emergency department and they have a single seizure and end up intubated.
Speaker: So I think that just, I've also heard where a patient who
Speaker: has a small intracerebral hemorrhage and gets intubated because the image showed a intracerebral hemorrhage, even though the patient had a GCS of 14 is fully awake.
Speaker: So I think that looking at the patient overall and using all the things that you're seeing in the examination, whether they look like they're not managing the airway.
Speaker: In the medical world, of course, we typically intubate because of the inability to oxygenate or ventilate.
Speaker: And so it's a pulmonary reason, but for the neurologic patient,
Speaker: It's typically things like if you do think that that patient's imminent to have problems with, of course, herniation, that's the easier one.
Speaker: But I think that the patient who can't manage their secretions very well, so someone who looks, that's why we use that GCS of 8, because typically when they're getting to that level, their swallow mechanism is not working as well or adequately to support them.
Speaker: The patient
Speaker: patient with neuromuscular disease that has potentially hypercarbia as their cause, obviously they're intubating them for ventilation.
Speaker: It's looking at the entire patient, but airway first, make sure they're breathing adequately.
Speaker: And then for blood pressure, that's always the question, right, for the neurologic patient is what's adequate.
Speaker: And that is, it varies depending on
Speaker: what the disease process is.
Speaker: For the stroke patients with the acute stroke that aren't needing TPA, we typically, at least the guidelines had recommended, you know, treating it when it's greater than 220.
Speaker: I think most of us feel uncomfortable when it's quite that, you know, it's that high unless we know the patient is, you know, severely hypertensive at baseline, but, you know, maybe less than
Speaker: with the TPA, it's less than 180.
Speaker: And I think that's where many feel more comfortable with for stroke patients.
Speaker: For ICH, again,
Speaker: A little in debate still, we know that we want to be controlled.
Speaker: So some say less than 180, less than 160.
Speaker: The guidelines really are saying target between 140 to 150, but not less than 140 because of the risk of acute kidney injury when you tighten the blood pressure too much.
Speaker: So we don't want to over control it for ICH.
Speaker: For the TBI patient,
Speaker: The guidelines differ when you don't have an ICP monitor in.
Speaker: We know that you want the cerebral perfusion pressure, which is MAP minus ICP, greater than 60 when you have an ICP monitor in.
Speaker: But the most recent guidelines now state when you have just systolic blood pressure to look at that you want to target between 100 or greater than 100 patients.
Speaker: or greater than 110.
Speaker: And they were very confusing, and people might want to close their ears because it's too crazy to think about, but what they did was, and I think of it as a smiley face, when you're at the extremes of, the semi-extremes of age.
Speaker: So when you're greater than 69, you should be greater than 110, or you're less than, I think they used 18,
Speaker: No, I think it was, sorry, I'm trying to remember what the number was.
Speaker: I think it was less than 50 or 49 and lower, you would also be greater than 110.
Speaker: But in between that, you want to be at the lower part of the smiley face between ages 50 to 69.
Speaker: They said you should be 100.
Speaker: So I think that you should just be greater than 100 to 110.
Speaker: But those are the guidelines, which are a little bit confusing for people.
Speaker: But making sure you have adequate blood pressure is key to, of course, our cerebral perfusion.
Speaker: And sometimes we need to target a little bit higher and push things.
Speaker: Often people think about trying to push it to make sure that you're well perfused.
Speaker: And it just depends on whether your CTA might have shown some stenosis.
Speaker: And again, this is something that doesn't have a lot of literature behind it, but people have tried to do that.
Speaker: So those are the basic management of the ABCs.
Speaker: After that, we're thinking about if your patient has intracranial pressure, we're thinking about ways to lower that.
Speaker: So ahead of the bed up, which should be the case in most patients, especially when you're intubated.
Speaker: Of course, we keep our head of the bed up for VAP reasons.
Speaker: And then making sure that we're also giving medical, just giving the patient
Speaker: Fluid, when you're thinking about management of fluid, if they're an ICP issue, would you use hypertonic saline, potentially if they're dry.
Speaker: If they're very wet, fluid overloaded, mannitol might be a reason we can use those interchangeably.
Speaker: Otherwise, just even stroke patients, people forget.
Speaker: I see quite often patients come up from the emergency department without even IV fluid running.
Speaker: And you know that you want to make sure that patient has good perfusion and there should be an IV fluid running.
Speaker: People forget about those kind of basic things besides all the other usual prevention of harm that we do in the ICU, like putting on our SCDs and all the prophylactic things that we need to think about.
Speaker: Excellent.
Speaker: And you did mention ICP.
Speaker: And I believe that especially in the early phases when general intensivists are evaluating these patients, that might not be on the top of their list of looking for.
Speaker: So maybe we can talk a little bit more about it, Cheryl.
Speaker: Once you have obviously a way to measure it, you have, I mean, an intraventricular device or something, it's a lot easier to manage.
Speaker: But what should prompt us to think about this?
Speaker: What findings, edema, the type of structural abnormalities, findings in the eyes?
Speaker: What are the things that should prompt us to question, is the ICP elevated?
Speaker: Yeah, that's a great point.
Speaker: And actually, I mean, just putting together a lecture for our new fellows and residents, a reminder that, you know, that you don't need
Speaker: the tools always and the things that you should be thinking about, you know, the signs and symptoms.
Speaker: So if we have patients who are awake, they might have been complaining of headache before.
Speaker: But someone who often comes to us and we think that with increased level of, increased intracranial pressure, most people assume that they're going to have a depressed level of consciousness.
Speaker: But I can tell you, and especially in young people, people start getting agitated.
Speaker: They start kind of thrashing about, becoming, becoming,
Speaker: difficult to manage.
Speaker: And the first thought for people is to actually sedate them, which is the worst thing because they're partly protecting themselves by hyperventilating, you know, kind of sitting themselves up, trying to do these things.
Speaker: But the first thought is to sedate them.
Speaker: But
Speaker: You know, it is like you mentioned before that people are often looking at, you know, for papilledema.
Speaker: And, you know, with a history of long term headache, I think it is reasonable to still look at that in the ICU.
Speaker: It's not something we do frequently because we usually have some clue what's going on, but it's just something that could be there.
Speaker: But it's really headache.
Speaker: And then the agitation, but then blood pressure.
Speaker: So when the patient's agitated, also the blood pressure is going up and people often think, well, they're agitated, so the blood pressure is high.
Speaker: But remember, and I mentioned cerebral perfusion pressure equals MAP minus ICP.
Speaker: So when a patient's ICP is elevated, which you can't see because you don't have a monitor in, the MAP is going up to match that ICP to keep the cerebral perfusion pressure.
Speaker: Typically 70 is more what our normal is.
Speaker: In the TBI, we want it greater than 60, but the normal person, say MAP, is 75 because your ICP is 5.
Speaker: So you're keeping your cerebral perfusion pressure 70.
Speaker: But if your ICP goes to 20,
Speaker: all of a sudden you're going to move your map up to keep that CPP equal.
Speaker: But if you drop your map, like say someone says, oh, I just want to sedate the guy and put him on propofol, that will defeat the autoregulation.
Speaker: It'll drop the patient's blood pressure, and you haven't changed the ICP, and you've now decreased the CPP in that patient to something that's causing brain damage.
Speaker: Yeah.
Speaker: So I would caution people that when they're seeing a, they get, they hear a score, get a scan and sees an ICH, intracerebral hemorrhage or tumor, patient starts getting agitated and thrashing about.
Speaker: Think about ICP before you think about sedation and think about maybe whether you want to give
Speaker: either a dose of menatol or hypertonic saline, again, depending on what you think the patient's fluid status is.
Speaker: People think, well, I need a central line for hypertonic saline.
Speaker: But if it's a medical emergency, you'd probably rather have a sclerosed vein than a dead patient.
Speaker: So a large antecubital vein can be used with a large-bore IV and run it maybe over a half hour or so of a hypertonic saline, 250 of 3%.
Speaker: or of course, just giving mannitol in that situation rather than thinking about just sedating the patient.
Speaker: In those cases, of course, you might be thinking about other things like, well, if I intubate the patient, I need to be worried about also spiking their ICP.
Speaker: We have seen patients herniate when they get intubated.
Speaker: So thinking about giving preemptive lidocaine, which a lot of people aren't aware of.
Speaker: Our neuroanesthesiologists are quite aware that
Speaker: It's been shown to give a cardiac dose basically of one milligram per kilo of IV lidocaine can help blunt the ICP spike that occurs with endotracheal intubation.
Speaker: So that is an important factor as well as your usual RSI drugs that you might use.
Speaker: Again, trying to avoid the longer acting ones just so that you can follow an exam is important as well.
Speaker: Perfect.
Speaker: And you did mention, obviously, herniation, which would be the one thing we absolutely want to prevent and we want to save that patient.
Speaker: Any telltales of impending herniation that we can refresh our intensivist on?
Speaker: So the impending herniation, as I mentioned, the autonomic changes, the hypertension that occurs.
Speaker: Some people are waiting for the Cushing's triad.
Speaker: So with the hypertension, you might get the bradycardia.
Speaker: And then, of course, the ataxic breathing is the medulla is being compressed.
Speaker: I tell people not to wait for that.
Speaker: So watch for the hypertension.
Speaker: Of course, you may have early signs like we talked about.
Speaker: The pupilometer might pick it up.
Speaker: But even you might pick up that there's a very subtle...
Speaker: and isochordia, so that's a sign of impending herniation as well.
Speaker: So those examinations, so if I see a patient starting to thrash around, you know, just
Speaker: shine a light in that patient's eyes and see what's going on there and sit the patient up as well as thinking about securing the airway and giving them osmonics.
Speaker: And of course, we didn't talk about, but hyperventilating, which is felt to be best around 30 to 35 millimeters of mercury and PCO2.
Speaker: So we talked about the general approach with the ABCs and some specifics of thinking about ICP.
Speaker: And ultimately, the goal here with these patients is to try to identify the etiology and that will dictate what are the specific therapeutic interventions that would benefit that patient.
Speaker: And
Speaker: It would be, I mean, beyond the scope of today's conversation to dive into each one of those.
Speaker: But the last thing I wanted to talk about, Cheryl, regarding treatment is our approach to care in terms of transfers, location.
Speaker: A lot of our listeners might work in hospitals that just have a general medical surgical ICU.
Speaker: Some might work in a place that has a neurocritical care ICU, but also in terms of, I mean, a lot of these patients will be managed in surgical or medical or medical surgical ICUs, but when should we start of involving our neurocritical care colleagues or when should we think of transferring patients either inter-facility or inter-facility and those that have that expertise?
Speaker: Yes.
Speaker: And that is a tricky part.
Speaker: We,
Speaker: There were standards created for neurologic critical care units back in 2018 to kind of give an idea of what you can expect if you're looking to send a patient to different neuro-ICUs so that you have a clue of what you're going to get by sending the patient there.
Speaker: But I think that looking at it from a general standpoint, it would be where your modalities for evaluation may not be adequate.
Speaker: different type of imaging technology that is needed.
Speaker: Say your facility doesn't have, and this isn't the case for the most part now, but for an MRI, many do send patients for monitoring where they are aware that their patient probably is in status and cannot adequately monitor them
Speaker: with continuous CEG.
Speaker: So some is for technology, whether it's for imaging and workup or for continuous monitoring for treatment.
Speaker: And then others for expertise, you know, it's often centers that when you have a more advanced neurocritical care, it's the neurosurgeon that you're going to need to be able to, and that's probably the most common reason why patients get transferred is that
Speaker: it's clear that the patient has a mass lesion or something that it needs to be.
Speaker: And I know that that's a pretty simple bar to recognize is that this sounds like it may need a neurosurgeon.
Speaker: The only thing is that many people try to think that even a small intracerebral hemorrhage needs transferred because of the need to evacuate that.
Speaker: A lot of the
Speaker: data have so far supported that trying to evacuate a deep intracerebral hemorrhage does not necessarily improve outcome.
Speaker: Now, recent, there's a new study that's coming out that may show that minimally invasive ways of extracting the hemorrhage might be helpful, but for the most part, and a consult, and it's, I think, really important to have potentially using tele-ICU or tele-consultation
Speaker: with a neurocritical care team that might be down the road or in a closed state would help you determine whether that patient is going to benefit from leaving the center that they're at where their family can be around them to a place that's more remote and more difficult for family and support systems.
Speaker: to come to.
Speaker: So if there's definitely technology, you know, and I forgot to mention things like plasmapheresis is another reason why, but going back to the people, it's really the neurosurgeon.
Speaker: And then, of course, the neurointensivist, we do have extra training that allows us to not only know our general critical care, but help
Speaker: add the neurologic evaluation and decision making that can be helpful as well.
Speaker: So that's the time that you would think about potentially transferring the patient.
Speaker: With our new technology, though, I think that there are more and more cases of using telecritical care or tele-neurocritical care or trying to, and not just for monitoring, but even just for consults to get that input when it's not going to be very feasible for a patient to be transferred.
Speaker: They don't need the technology necessarily that's at the other site, but more the input process.
Speaker: and assistance in working as a team and helping out that way.
Speaker: So sometimes we don't have to transfer the patient for that particular act unless it requires the technical aspects of that specialist.
Speaker: Excellent.
Speaker: Well, I think that ultimately the take-home message really is to use, I mean, a systematic approach to these patients, right?
Speaker: I mean, I think the framework that you presented of us thinking of structural, functional, infectious, inflammatory, and pharmacological categories is a great place to start, and that will help organize and make our evaluation of these patients much more efficient.
Speaker: And once we have a diagnosis, I think that it's a lot easier to figure out what the next steps are within treatment.
Speaker: But like we said, Cheryl, I think this is a very common and important topic.
Speaker: So I appreciate your expertise in sharing all this with us.
Speaker: And it is customary for us to close the podcast with some questions unrelated to the clinical topic.
Speaker: Would that be okay?
Speaker: Yes.
Speaker: So my first question relates to books.
Speaker: And are there any books or books that have influenced you or that you have gifted often to other people?
Speaker: So it changes with time.
Speaker: So in the beginning, you know, and depending on where someone is in their training, I think those key core textbooks like LEN or DEMO,
Speaker: Dr. Perillos and Dr. Dellinger's, you know, those big textbooks, but people don't learn very much by big textbooks so much anymore as being able to go into the Internet, search and review different topics.
Speaker: For me, some of the books, if you're interested in the neurologic aspect, the one that I found most useful starting out and the one that I've gifted and even now gift to our APPs that are starting in neurocritical care is...
Speaker: Steven Goldberg's clinical neuroanatomy made ridiculously simple, starting at the basics, because as I talked about, a neuro exam doesn't have to be difficult.
Speaker: And the fun thing about, I think, the neurologic system is by evaluating, examining the patient, you can figure out where the pathology is and know where you need to target.
Speaker: So that is a book.
Speaker: But I think in general critical care, and actually one of the ones that I found most helpful, and at one point,
Speaker: had asked that the nurses all read this because it really helps, I think, it helped me with empathy, also was a book that was called Bed Number 10.
Speaker: I think the author is Sue Bayer, and I think she wrote it with someone else.
Speaker: But it was about a Guillain-Barre patient.
Speaker: It's her experience of being in an ICU bed,
Speaker: not being able to communicate, but being aware and not being able to, so she couldn't move anything.
Speaker: And, you know, this is kind of the nightmare.
Speaker: And even, you know, the patients you hear about that have paralysis without adequate sedation.
Speaker: I mean, that's the nightmare of not being able to move.
Speaker: So she brilliantly describes how
Speaker: I'm very poignantly how like a fly is buzzing around and lands in her nose.
Speaker: She can't do anything.
Speaker: Or when she was hot and the nurse didn't try and communicate her, she covered her with all these blankets.
Speaker: And so it made me more empathic of recognizing how important it is to try and communicate with patients or determine whether they have their conscious under this decreased level of consciousness that we're perceiving.
Speaker: Because I think that's really important that the patient may be more aware than we think also.
Speaker: and trying to find ways to communicate.
Speaker: There are different tools and technology that for patients who are, say, quadriplegic, or in a patient like this where she can't even move her eyes, it's even more difficult.
Speaker: But I think being aware, trying to be very cognizant of evaluating that patient every day to see if there is consciousness is so important.
Speaker: And then, and
Speaker: helping that patient as much as possible, being able to communicate.
Speaker: Because I think that for many of our patients, if you ask them, the most frustrating thing is not being able to communicate with their nursing or medical team and family to say what their needs are.
Speaker: So that bed number 10, I think, is probably the most...
Speaker: important book throughout my career that I've shared with nurses and other, um, other people who, who manage patients in the ICU.
Speaker: Excellent.
Speaker: And we'll definitely, I mean, put a link in the, in the show notes.
Speaker: I have not read that book, but definitely interested in picking it up.
Speaker: There is a similar, not maybe similar, but I think along the same lines, a book that has made me rethink a lot of our approach to end of life, but also to our patients.
Speaker: Um,
Speaker: called The Diving Bell and the Butterfly, which is about a locked-in syndrome patient who was basically thought to be done.
Speaker: And he wrote the book after surviving that neurocatastrophe.
Speaker: He eventually did die.
Speaker: But I think, again, just, I mean, empathy, it seems that there's always opportunity for us to be a little bit more empathetic, right?
Speaker: I mean, and really put ourselves...
Speaker: in the position of our patients and understand what it means.
Speaker: So I definitely will, we'll look for this.
Speaker: Thanks Cheryl for, for, for sharing that.
Speaker: Just to mention with that book, he, he blinked through the alphabet.
Speaker: They figured out an alphabet way of, uh, and using the most common letters first, you know, for one blank, two blanks.
Speaker: It's just incredible book.
Speaker: You're right.
Speaker: It is.
Speaker: The second question relates to, to beliefs and what do you believe to be true in medicine or in life that most people don't believe or act like they don't believe?
Speaker: I don't know if they don't act, but I think we forget sometimes.
Speaker: And I think I'm somebody who's very curious that my big word is always why.
Speaker: And I think that's true in the topic we're talking about is why is this happening?
Speaker: When we look at our notes,
Speaker: Sometimes people see a problem and go straight to their plan, and you're looking at what the why is, and the why drives everything.
Speaker: And it's not that people don't believe it, but they forget to either clarify that or sometimes don't go into the why.
Speaker: They focus or target in on one thing without asking, really, why is this happening?
Speaker: Why would that happen?
Speaker: Why does this patient look like this?
Speaker: and go through a differential.
Speaker: I think people often anchor in a single thing that often is a reason to make mistakes.
Speaker: But I challenge people to stop just going straight to a plan and go really into the whys of things, even a drop, a little drop in the, say, the hemoglobin.
Speaker: It's like, why did that happen?
Speaker: You say, oh, that's hemodilution.
Speaker: Well, is it really?
Speaker: Or just different changes that occur,
Speaker: that are very subtle that, you know, sometimes a patient can have a PE and you think, and you're focusing on that when you miss the pneumothorax, the very tiny or enlarging pneumothorax and people are going down the road of a, you know, PE.
Speaker: So I think just thinking about why's and, and
Speaker: and not forgetting that when we're addressing a patient and not just anchoring on one thing, which is why it's going back to our topic here is that structural, you know, that different approach of starting with structural, but going through a framework of not just anchoring on one thing, but looking across a framework to look at the whys of this, why this might be happening to somebody.
Speaker: I think it's an excellent point.
Speaker: And it reminds me of one of my mentors in residency would always say that the best medicine is more often about good questions and having the answers, right?
Speaker: And really probing and probing, I mean, to try to understand a little bit more.
Speaker: That's a great point.
Speaker: So our final question is, what would you want every intensivist who's listening today to know?
Speaker: Could be a quote, a fact, or just a thought.
Speaker: So my favorite quote, and the people who know me best, and
Speaker: and I just recently changed institutions, and I met a lot of people coming in from different institutions, and knowing that evidence base is changing is a quote that I heard from the late Rear Admiral Grace Hopper, who, she was a computer scientist and made a lot of changes in computing, but she said the most dangerous phrase that we can use is, we've always done it that way, and I think that
Speaker: sometimes even though it's just standard practice to try and be safe, make sure things are doing, you know, being done the same way, that we need to always think about how we use our evidence base, how we use exploration and changing the way we do things to be better.
Speaker: And so always doing things that way doesn't mean that's the way we should always do it.
Speaker: It means that we use our, you know, our
Speaker: Our literature is full of people exploring new things and looking at different ways of doing things.
Speaker: And I think we need to be change agents and be willing to make changes in our practice and not always do things the way we've done it.
Speaker: I agree, and I think that's a perfect place to stop.
Speaker: Cheryl, thank you so much for sharing your expertise and your time with us.
Speaker: I look forward to having you back to talk about other neurocritical care topics, and I hope you have a great summer.
Speaker: Great.
Speaker: Thank you, and you too, and thank you for asking me to participate, and this is a great service you're giving to the critical care community.
Speaker: Greatly appreciate it.
Speaker: Thanks.
Speaker: Thank you for listening to Critical Matters, a sound podcast.
Speaker: Make sure to subscribe to Critical Matters on Apple or Google Podcasts and share with your network.
Speaker: Sound's transforming the way critical care is provided in hospitals across the country.
Speaker: To learn more, visit www.soundphysicians.com.
