Brain Death Testing

Welcome to the East Stroma Cast. Advancing science.

Welcome to another episode of the East TraumaCast. Thank you to Humanetics for their generous and unrestricted grant for the Educational Resources Committee and TraumaCast. I'm Zach Cassim, an associate professor of emergency medicine, critical care, and pre-hospital care at the University of Pennsylvania. Uh one of the less common but certainly more challenging aspects of critical care management can be the determination of brain death.

Given its legal implications, it remains imperative that we do this determination correctly. So to assist us, a recent consensus practice guideline was published in the journal Neurology in October 2023 that really consolidated and updated joint recommendations from the American Academy of Neurology, the American Academy of Pediatrics.

the Child Neurology Society and the Society of Critical Care Medicine. An additional summary document is available in the March 2024 issue of Critical Care Medicine, and we'll provide some links to these articles in the show notes. But I'm glad to say that we have two of my Philadelphia based colleagues here to discuss the intricacies of these updated guidelines, Dr. David Fisher and Dr. Matthew Kirchin.

So thank you so much for taking the time today to inform our listeners. And can you just please start by introducing yourselves? So yes, I'm David Fisher. I'm an assistant professor of neurology.

at the University of Pennsylvania. I'm a neuro intensivist and I spend most of my time in the neuro ICU. And so I can speak to this issue from the perspective of someone who does brain death determinations in adults on a semi-regular basis, and who has also written our local policy for adults in the pen medicine health system.

My name is Matt Kirschan. I'm an associate professor of anesthesiology and critical care medicine, neurology and pediatrics at the Children's Hospital of Philadelphia and the University. of Pennsylvania. I'm a pediatric neurointensivist, and I was one of the authors of the 2023 guidelines. Fantastic. Thank you again for being here for this. So why don't we start off with the definition of brain death? Is there a standardized definition that we should be using?

Brain death is medical and legal death. It occurs in patients after catastrophic brain injury. It is a clinical diagnosis and it is the Permanent loss of all functions of the entire brain, including the brainstem, as evidenced by coma, brainstem a reflexia, and absence of a respiratory drive and the setting of an adequate stimulus.

There's been a significant gap, almost a decade, I think, between the last consensus statement that's come out regarding brain death testing. Why did you decide that now's the time to bring a new guideline? So many clinical guidelines are updated every five to ten years, and so we felt like this was a natural time in order to revisit the scientific literature and revisit what had been

published in the brain death space. There had also been many advances in critical care medicine, including ECMO, the use of therapeutic hypothermia. uh strategies to treat intracranial hypertension, as well as some new things that had been written about in the bioethics literature, like brain death and pregnancy. We also realized that there was adult guidelines and pediatric guidelines

And of all things in medicine, determination of death should really be independent of age. And so we took this as an opportunity to combine the adult and the pediatric prior guidelines into a single document. so that we could have guidelines for death determination independent of age.

You mentioned age. I noticed in the guidelines there is a a small subcategory in the pediatric group that is excluded from these guidelines. Can you talk a little bit more about that? So the only group that is excluded from these guidelines is premature in And that is in part because there has been No literature published on the validity of these criteria for determining brain death in a premature infant.

Similarly, a lot of what the neurologic exam does When you are assessing a patient for brain death, is look at the cranial nerve reflexes, and those reflexes develop as Fetuses are developing. And so depending on how many weeks a premature infant is when they are born, they may not have developed certain of those primitive reflexes that we test in the

I'm sorry, cranial nerve reflexes that we test in the brain death evaluation. And because of that, infants less than 37 weeks correct digestational age are not appropriate to be evaluated by these criteria.

So with the significance of brain death testing and now having these guidelines there, it clearly provides us a roadmap for what to do and how to assess these patients. Anecdotally though, have you noticed or even in the published literature, has there been Problems that have arisen with regards to how brainstem testing has gone and perhaps not done the right way and ending up in inappropriate outcomes, shall we say?

So there have been no documented cases in the literature where the guidelines have been followed appropriately and there has been evidence of recovery or persistent neurologic function. There are several cases which are written about in the media and the popular press where somebody recovers from brain death.

And in those situations when, you know, the cases have been interrogated, usually one of the confounders has not been excluded. But if the guidelines have been followed as the way that they have been published, both the prior guidelines and the new guidelines, then there has not been a published case of somebody recovering neurologic function after an appropriate determination of brain death.

Getting together this large group of people must have been quite a feat. Everybody in their own societies has varying opinions on on different issues. What was the process for getting everybody together to make these recommendations, which clearly have huge implications on our clinical management for this group of patients.

Yeah, so the American Academy of Neurology has a process for doing the guidelines. They were the organization that had done the prior adult guidelines, the prior pediatric guidelines. were a multi-society guideline of AAP, CNS, and SCCM. And so we felt like it was important to bring all of the stakeholders to the table, the critical care societies, the neurology societies, the pediatric society, who all have a stake in the care of critically ill patients with brain injury.

and the determination of brain death. And so we used the infrastructure provided by the American Academy of Neurology and their guideline development committee. We had representation from all of the different societies. And ultimately the document was approved by the boards of all of the partnering societies.

Well done on getting that group together and putting this out. It's a fantastic document. Doctor Fisher, can you explain to us who is qualified to do the brain death exam? Can it be Any of us in the intensivist realm or do you need to be specifically trained for this?

Yeah. Within our health system we do advocate for specific training and I I know a discussion Matt and I have had is what should that training look like? What should be the minimum amount of training that's required to do brain death testing? Right now there's specific guidance in the national guidelines as to who can and cannot do brain death testing. Matt, you can correct me if I'm wrong. I think locally we have felt like some kind of minimum competence, minimum training.

would be helpful to help reduce uh some of the errors you alluded to if you know the policy isn't followed by the letter of the law. It's a little bit of a balance because on the one hand, you want to be able to make people feel confident in doing brain death testing correctly. On the other hand, the more stringent you make the training,

the less accessible it potentially becomes. And if you're thinking about rolling out a brain death policy to a health system, that can become really challenging if you don't have enough people who are able to do that sort of testing. Ultimately, locally, we've developed a hybrid approach of having both virtual training modules. uh as well as in-person or didactic training that then allows any in intensivist, neurologist, or neurosurgeon to be able to perform brain death testing.

I will say that there are state laws that can sometimes become relevant here. Our health system spans across Pennsylvania and New Jersey. Pennsylvania law does not dictate who can and cannot determine brain death. However, New Jersey law does and does require

it to be an intensivist or neurologist. Whereas in our health system in Pennsylvania, in theory, say an internal medicine trained physician could undergo that training to do it in Pennsylvania, that would not be allowable in states like New Jersey. The two other things that I'll add is per the guidelines, it must be an attending physician. Trainees can participate, but they must be directly supervised.

Advanced practice providers who often work in many of our ICUs can be trained and competent in doing the brain death evaluation, but their ability to do it independently uh must be done in accordance with institutional policy and state laws. There are some institutions and some states that will allow APPs to do them independently and others will not. There are also some national

certification courses, particularly one through the Neurocritical Care Society. If there is not a local course at your institution, there are some national courses that you can sign up for that are available online. I think that nicely rolls into the next question I had. Especially I think overall we're in our practice we may not have the opportunity to be participating in this or see this. So for fellows in training in particular, can you elaborate a little bit more on those?

opportunities to train and perhaps even for or those working in the community who may also not have had to do this since their training, what refresher in addition to this document can they get to really feel confident in being able to do? So there's many of these online courses, there's many societies that offer simulation based courses at their annual meetings.

That are half-day courses where you can actually learn from an expert on a mannequin, which is actually the perfect environment to put yourself on a brain desk. examination. And so we encourage people actually to do the didactic portion, which can be online and then do an in person simulation based course in order to remind themselves of the mechanics of doing both the neurologic examination and the apnea test. That's fantastic.

And then going back to a little bit about the state to state variation, one of the questions that I wanted to ask both of you is As the intensivist undergoing or about to undertake the brain to death test in my patient, do I need to obtain consent to do this, especially given the implications of it? And does that vary from state to state? We can speak to this so yes, there is some state to state variation.

The national guidelines as a whole does not mandate that consent be obtained from family members in order to perform or declare brain death, the rationale being if you think about cardiopulmonary death, we do not typically ask a family's permission in order to establish that those patients have died. And so by a similar rationale, nationally there's not a feeling that consent is mandatory for these patients.

However, the argument has been compellingly made that maybe that that's something we should be thinking about, right? So if you think this brain death testing is not risk-free. You know, if you think about the apnea test, for example, there can be complications of that. And when we think about conducting that in a patient who's still

medically legally considered alive, how do we think about taking those risks in terms of consent? But again, broadly, the feeling is that we do not necessarily need to be approaching these families for consent. That being said, a couple of caveats I would add to that is that does not mean that we should be avoiding communication with family. I think thorough, frequent communication with family to explain what we're thinking, what we're doing, what this means is extremely important.

And there are states that are exceptions to this. For example, in states like New Jersey, they accommodate religious objections to declaring brain death. So in the state of New Jersey, if the patient's family indicates that the patient would not believe in the concept of brain death religiously, if there's any documentation that indicates that, then physicians are not allowed to declare those patients as brain dead.

Now, those laws typically do not prohibit p physicians from doing brain deaf testing. But if that testing is ultimately compatible with brain death, physicians are legally not allowed to declare brain death if those patients are considered to have a religious objection. Yeah, that's very useful to know. So given all that, at what point do I say as the intensivist that my patient is ready to undergo brain death testing? What kind of criteria do I need to fulfill?

So I think and Zap, the question is when do I know what that's okay to start brain death testing or what is the actual criteria for brain death testing? Okay. From my perspective, brain death testing is appropriate at any point in which a physician feels that the patient may have permanent loss of all brain function as a result of their Acute catastrophic brain injury. If a physician feels like that has occurred,

and is sufficiently convinced that is not confounded in some way, then it is appropriate to start thinking about, are all my preconditions met and can I therefore move forward with brain death testing. It's whenever a physician intuitively feels that a benchmark has been reached. I will say that one of the things along those same lines that I teach in the brain death courses and we write about is that I have a pretty high bar for that definition of permanence. And you want

both a clinical exam that is consistent and neuroimaging, electrophysiology if you have it. And then you need to wait an appropriate amount of time in order to convince yourself that the patient is not going to have any recovery of function. And there are time intervals in the guidelines after cardiac arrest in particular when

is a common occurrence with hypoxic ischemic brain injury. We tend to wait longer in children than in adults, but this is one of the few decisions in medicine that we can't take back. And you wanna be a thousand percent certain that the patient is not gonna have any recovery of function. before you initiate that evaluation. So my mantra is when in doubt, wait longer, observe the patient longer to really be confident that they have permanent loss of brain function.

And I think what I think you'll allude to in the document too, and I think that's particularly relevant relevant in our population, certainly in Philadelphia and around the country, I believe, as well as the confounders from toxicological issues and things as well that may be present. And just to follow up on Matt's point, I think so the the guidelines say waiting twenty-four hours from the acute brain injury, and if it was a cardiac arrest.

uh 24 hours from return of spontaneous circulation or initiation of ECMO is the minimum as Matt alluded to, but there might be circumstances where it does make sense to wait longer. He mentioned that the pediatric circumstance, uh, a common situation in adults, might be if you've just relieved intracranial pressure by placing an EVD, for example, you intuitively might want to wait a little bit longer to see what the effect of that is before concluding permanence as well.

I was gonna come back to the confounder issue that you talked about and the intoxication. This is one of the most challenging aspects of brain death testing is really to know when you have reached that permanency bar.

And intoxication makes it very difficult. And it can be intoxication with drugs of abuse. It can also be intoxication with usual medications that we use as part of Clinical care, especially in patients that have some sort of renal or hepatic insufficiency or failure as part of their multi-system organ failure from whatever cause. their brain injury. It is absolutely crucial to make sure that you have complete clearance of all potential intoxicants.

and medications that can impact the central nervous system prior to doing brain death testing. if there is a way to measure the level of the intoxicant or the metabolite To ensure that they have adequately cleared, please do. If there are medications, we commonly use sedatives in the critical care and the emergency setting in a therapeutic context. There is now a very large table in the guidelines which talk about the half-life.

of the various medications and it's important to wait at least five half-lifes to know that those medications are adequately cleared out of your system. Most of us in the ICU work very closely with our pharmacists and we will ask our pharmacist to weigh in To ensure that Patients have adequate clearance of those medications. In circumstances where patients have had

quoted recovery of brain f function or there has been some evidence that there is a neurologic function after an exam has been consistent with brain death. In most of these situations the confounders have not all been adequately given appropriate time in order to make sure that Things like medications and intoxicants have totally cleared from the system. In my mind, doing this step of the brain death evaluation.

is the most important step. Yes, the exam is important and you've got to do it rigorously and the apnea test, you need to do it safely, but you really need to make sure that there are no confounders.

to the exam, particularly medications taking into things like temperature, obesity, renal and hepatic injury that I spoke about, and then also issues like temperature and blood pressure and other metabolic considerations to make sure that the validity of your exam is unconfounded by any of these things that can impact the central nervous system.

Really great points. So now that I've determined that it's appropriate to proceed, how many tests do I need to do? And is there a difference between adult and pediatrics? Yeah, so the national guidelines mandate at least two examinations for pediatric population, but just one for the adult population. That being said, there are still a lot of institutions like ours that have decided that it makes sense to implement two even for adults.

The idea being that as Matt said, you don't want to get this wrong, right? Out of kind of an abundance of caution to make sure that there aren't any kind of fluctuations in the examination that you might be missing, we and many other institutions have mandated two examinations for adults as well. And there's then the question that if you are one of those institutions that are implementing more than one examination, how long do you wait between examinations? Again, there's variability there.

In a pediatric population, the exams have to be at least twelve hours apart. In adults, again, because not war more than one examination is actually mandated, there's a lot of variability between institutions as to how long you wait. There's no rules around that. And again, it's really a balance between prioritizing rigor on the one hand by waiting longer between exams and also declaring brain death in a timely way.

I will reinforce, as Dave said, the time between those two exams is arbitrary. The most important interval is the time from the brain injury until you start. You have to establish permanency before you start. And so the time between the exams is not meant to be an extra cushion of observation. The important thing is, right, you've got two independent exams for the purpose of having two people conclude the same thing for reassurance.

But don't count on that time between exams as built-in extra time for observation. You have to be confident that the brain injury is permanent before you start. Really important point. I like how you

continue to emphasize that for our listeners. You highlight a number of c the components of the the testing and the document. I think one that's particularly relevant to our surgical and trauma critical care population is performing the Oculus of Falc or the doll's eye reflex in someone who

may have a suspicion of cervical spine injury or we've been unable to clear their cervical spine because they've not been able to participate in an exam. So does that preclude us from doing brain death testing? We need to make sure that we assess each one of the cranial nerves. And there are two different tests that can assess the eighth cranial nerve, which is the OCR and the OVR, the oculocephalic reflex and the oculovestibular reflex.

The oculocephalic one being the doll's eyes, where you rotate the patient's head. side to side that is potentially concerning if you have a known or suspected a cervical spine injury. And then there is the OVR, which is the oculovestibular reflex, and that is the one where you squirt the cold water in the patient's ear and look for eye movement. The OVR, the cold calorix, is actually a more potent stimulus to test the cranial nerves than the OCR.

And in the domain of assessing the eighth cranial nerve, in particular in this situation, if you are available, if you are able to do the OVR or the cold caloric, then you can not do the doll's eyes or the oculocephalic reflex and still be able to complete the clinical brain death testing. It is the only aspect of the clinical brain death examination

that can be deferred in the context of known or suspected C spine injury and still be able to make the clinical determination. There are some hospitals that because the two maneuvers both test the same thing, actually do not do the OCR. routinely. There are other hospitals like ours that say we want to be as conservative as possible. If you can do two tests

That assess the same reflex, then let's be extra certain that those cranial nerves have no function. And the guidelines recommend in most hospitals. include both the OVR and the OCR in their protocols while acknowledging that if the OCR can't be completed, if the OVR is completed and does not show any evidence of function, then a brain death determination can be made in that context. I was gonna switch topics saying completely unrelated. Please. Okay.

Zap, just to backtrack, one topic I want to make sure we don't miss because this is probably a question that I get asked more than all the other questions that we've discussed so far is this question of toxic metabolic derangements confounding the exam and what level of toxic d metabolic derangement precludes brain death testing? It's a very common question, it's a very tricky one.

So just to highlight the fact that there are it's really up to the clinician's judgment as to what levels of toxic metabolic derangements would be sufficient to confound the exam. The national guidelines have included a very helpful table on some rules of thumb as to what sodium levels or ammonia levels might might cause you to question whether or not to move forward with brain death testing, but it is ultimately left up to the judgment of the examiner.

And that can be tricky. The way I try to counsel physicians through this is A lot of physicians have seen a wide array of toxic metabolic abnormalities and have seen their clinical manifestations. I think the question that physicians should have in their mind, is this a toxic metabolic derangement that I believe could realistically contribute to a combination of unconscious, unresponsiveness and brainstem a reflexia?

Um for example I think, for example, a lot of physicians might start to get nervous around sodiums in like the high 150s, 160-ish. But how many physicians have really seen a patient with a sodium of one sixty? lack all of their brainstem reflexes. That doesn't happen very commonly, arguably ever. So just to make the point that ultimately that is a clinical judgment. It can be a tricky one, but I find that to be a helpful kind of rule of thumb for how to think through that.

Fantastic, very useful.

So let's move on to apnea testing. There's been some variability in the number of tests required for apnea testing as well. What does the new guidance say? And is there any difference again between adults and pediatrics? So similar to the neurologic exam, in adults, a minimum of one apnea test is required. in pediatrics, a minimum of two apnea tests is required. The way I see it is really the apnea test is part of the

neurologic examination, right? It's testing the respiratory centers and the lower brainstem. And so as part of our neurologic exam, our goal is to assess the entire brain, including the brainstem. And so the acne test Is just an extension of the neurologic exam and a test for spontaneous initiation of respirations in the context of a hypercarbic and acidotic stimulus.

And if we have a patient who we certainly get patients, especially in the adult community, that has C O P D and chronic hypercarbia, but sometimes we just don't know whether they're chronic hypercarbic patients. A lot of our trauma patients, for example, We just aren't able to get any history from them at all or find any families. So what do we do in that situation in terms of adjusting the interpretation of the apnea test?

So yeah, there is a little bit of a clinical judgment to make, right? For a lot of our patients, we don't know their entire history, but if you have no reason to believe that they have chronic hypercarbia, then you can move forward with apnea testing with kind of the usual parameters. But if you have some clinical reason to believe that they that they may have chronic hypercarbia, but you don't know their baseline PCO two.

Then you can give it your best guess. You have to normalize pH and CO2 prior to initiating the apnea test. So if you have a patient who you suspect to have chronic hypercarbia. Then you make your best guess for what their PCO2 is and ensuring that their pH is at a normal level between 7.35 and 7.45 will help provide some confidence to that.

And then you proceed with the apnea test as usual. But because there is this uncertainty about what their baseline PCO2 is, and because there's a possibility that you haven't given them a proper PCO2 stimulus. that even if that apnea test is ultimately compatible with brain death, you then need to do ancillary testing afterwards to provide additional confirmation of it.

Got it. So that's great for the clinical points. But w when do we decide to use ancillary testing? Is there any guidance on that? With the apnea test specifically or in No no it's it's uh ancillary testing in general, uh in terms of uh determining brain death. So the new guidelines have really de-emphasized ancillary testing. that the goal is to do is to make a clinical diagnosis of brain death using the neurologic exam.

And the apnea test, although we realize that there are some situations in which no matter how long you wait, you're not going to be able to resolve a confounder. For example, in a trauma patient, if they've got an ocular injury, no matter how long you wait, the pupil is not going to be able to be assessed and you're not going to be able to look at ocular movements accurately. And so that is a situation where you could move on to use ancillary testing in order to support the diagnosis.

If you have somebody whose ARDS is uh so severe that you are unable to safely do the apnea test, then you can defer the apnea test out of concerns for safety and do an ancillary test. instead. I don't like to think of it in terms of the ancillary test is uh replacing. the neurologic exam in these situations you have done the neurologic exam to the extent possible and it is consistent with brain death, but you need since you can't do the entire exam, you need an additional piece of data

that uh gives you information about the severity, the irreversibility, and the permanence of the neurologic injury. And in those situations, you can use ancillary tests. Specifically, the guidelines call out that you can not use ancillary testing. in situations where waiting longer, particularly with respect to medications, intoxicants, hypothermia, those types of things, will get better with time. The guidelines recommend waiting more time.

rather than doing ancillary testing in those circumstances. If I can just highlight a few of those points,'cause this is a very common question that I get as well about ancillary testing. Just to echo what Matt said, ancillary testing should only be done If the brain death evaluation cannot be completed, or if the brain death evaluation yields uncertain findings.

So again, if the clinical evaluation is compatible with brain death, it is not appropriate to just throw in an ancillary test for additional confirmation. It really is reserved for those situations where you cannot complete the examination. an apne test or they yield uncertain findings. The second thing that I wanted to highlight is that as Matt alluded to,

If you know you need to move to ancillary testing, you still must complete the clinical evaluation to the fullest extent possible. And I see this. as a common misstep is that if you're doing the first examination and that you can't you're not able to open one of the eyes, or even before you even start the examination, that the patient has some kind of injury that would confound the exam.

There is sometimes an impulse to say, okay, I know that this clinical examination is not going to give me what I want. Let's just move directly to the ancillary test for the sake of efficiency and time. That's not appropriate. You still must do however many clinical examinations is mandated by your local institution, you still must do the apnea test if it is considered safe. And only after those have been completed to the fullest extent possible.

Is it appropriate to then do ancillary testing last? And the logic for that is there still may be some other finding on the examination that is incompatible with brain defense. Right? You might know in advance that you're not gonna be able to check the patient's pupils, but you may find that they have a little bit of a cough. And therefore you've saved yourself the effort. You've saved the patient from whatever risks might be associated with that ancillary testing. Really useful info.

Two patient populations that you discussed in the guidelines that are relevant to us in particular, one is the patient on ECMO. So that was a new patient group that was included in this guideline. Can you talk a little bit about what considerations we need to have for those patients? So for patients on ECMO you should have exactly the same considerations as you do for patients not on ECMO.

They still need to meet all of the same criteria including catastrophic brain injury and need to be observed to make sure their brain injury is permanent, and they need to have a neurologic exam that has evidence of brainstem a reflexia and coma. The only thing that is different in patients on ECMO is completing the apnea test.

For patients on VV ECMO, the apnea test is completed the same way that it is for patients not on ECMO, and you can adjust the sweep flow in order to allow their CO2 to rise for serial blood gases. It gets a little bit more complicated for patients on VA ECMO. The goal is that you want to estimate the pH and the PACO2 and the cerebral circulation. And if you have patients with ECMOFLOW and native myocardial output, then there may be a mixing point somewhere in the aortic arc.

And so you often need to send multiple simultaneous blood gases from different locations based on the d whether the patient has intrinsic myocardial function and the location of your ECMO cannulas. And then all of those blood gases need to be consistent with the criteria. But everything up until acne testing is exactly the same. And the guidelines very explicitly lay out how to do the acnea test if a patient is on VA ECMO, including differences for cannula location.

It's very useful to know, especially as we're using this modality more commonly. And then the second group is that I think that probably challenges all of us are those with primary posterior fossa injuries, which can be a real clinical challenge to determine. So w what's your advice on that group of patients? I think this can be really confusing for a lot of clinicians, neurologists and neurointensivists included.

You asked at the early on, when do we know it's appropriate to proceed with brain death testing? And our answer was whenever you are sufficiently convinced that there has been permanent loss of all brain function. And that does not really include someone who has isolated posterior fossa injury, by which we're talking about someone with, say, an isolated brainstem infarct or bleed.

Uh because the rest of their brain might ac actually be operating okay. Or it might not be operate operating normally, uh, but it is operating to some extent. But it's important to know because uh a patient with an isolated brainstem lesion. could fulfill all of the practical criteria for brain death, right? They may be unresponsive, they may lack all of their brainstem reflexes, they may have apnea.

And so if you're not careful and you're not really asking yourself the question of has this patient really lost all of their brain function, you might fool yourself into declaring brain death in someone who has not really met the conceptual definition. of brain deaf. And I think a helpful thumb is Majority of our patients who pr progressed to brain death.

have what we call cerebral circulatory arrest, meaning that there is a catastrophic brain injury that is sufficiently widespread that the entire brain swells to the point that intracranial pressure exceeds mean arterial pressure. And whatever little islands of brain may have been spared by that initial injury, then become irreversibly infarcted as a result of no blood getting into the skull.

And I think it can be helpful to ask yourself that question. If you have a patient with a brain injury, you're looking at their scan, ask yourself, am I sufficiently convinced? that cerebral circulatory arrest has occurred. And if you're not convinced by that, if you still see, for example, gray white differentiation on one side of the brain between the cortex and gray matter, if that whole brain does not s appear to be wiped out.

as in the example of isolated posterior fossa injury, then it is not appropriate to even start with that brain death evaluation. It's really useful.

So a final question for primarily you, Matt, going back to the development of this fantastic effort and putting together this guideline, what recommendation or issue raised the most concern or controversy amongst the group in making a recommendation? That is a challenging question. I think the thing that raised the most controversy amongst the group was really one versus two examples. And I say that because the exam is intended to be objective.

And if it is done by a trained and qualified person, then one exam should be sufficient. However, I have the mantra that we need to do brain death 100% right a hundred percent of the time. And this is one of the few decisions in medicine that we can't take back. And there are other situations in medicine where we require two independent physicians to come to the same conclusion when the gravity of the decision is

sufficient such that it warrants extra confidence and extra scrutiny. And I think that this is one of those situations that having two independent physicians conclude the same thing, given the gravity and the implications. of a brain death determination is important. And we had people express both of those views on the panel that one exam and apnea test is sufficient.

and other people that said, yes, it should be, but given the fact that we are all human, we want to be extra confident in what we are doing. And so having a second provider confirm our findings. gives us all some level of reassurance that yes, in fact, this brain injury was permanent. They had no brainstem reflexes. Their apnea test was consistent. And so that's why, at least in the adult population, we came to the conclusion that a minimum of one exam.

was sufficient, giving each individual institution the ability to choose whether they wanted to do one or they wanted to do two. However, in pediatrics, consistent with both prior guidelines and the extra degree of confidence that we want to have doing this in the pediatric population that we maintained the two exam criteria. And just to piggyback on that, I think for any listeners who find that they don't have the time to read the national guidelines to the letter, which is understandable.

I think the way I summarized the updates is that it is in general more stringent than the guidelines before it. And I I think a lot of it is in line with that the spirit that that Matt just articulated, which is that Th there have been reports of people doing this incorrectly and so I think the spirit of the new guidelines are really to apply

additional rigor to this problem to minimize that possibility and hence the the two examinations, at least for pediatrics. And for example, whereas before it was sufficient to just give some kind of central noxious stimulation with a sternal rub, now uh there is a series of noxious stimuli that have to be delivered that you have to stick rigid q tips into the nose and

Apply noxious stimulation to different parts of the face. For the listeners, I would just say that the general spirit of the new guidelines is to be more rigorous and stringent. I will add to that for the listeners and I apologize one last thing is that if you are at an institution that has not updated your institutional protocol since the publication of the 2023 guidelines. I urge everybody to take that initiative at your institution.

There are checklists available. We design the guidelines in such a way that hopefully you can print them and very easily convert them into a hospital protocol. You can make a template for your EMR to easily document. the findings of the exam. There is an online tutorial that guides you through the various aspects of the exam and helps you determine whether you need ancillary testing.

Or not, please take this as an opportunity that if your institution has not taken that step to update the guidelines and has not had providers go through one of the educational courses since the update of the guidelines. Please take the initiative at your institution to make sure that you are compliant with the guidelines and that we are all doing this 100% right 100% of the time.

And to piggyback on that, I also make another point which is that reminds me of, because this can be a point of confusion. if your institution has not updated your local policy to reflect the new national guidelines, or if they have and there's some discrepancy between what the national guidelines say and your local institution says.

Follow your local institution's policy. That is what physicians are legally obligated to do. And th if there was a lawsuit, there might be a question as to why your local institution's policy does not reflect the national guidelines, but that will not be on the physician. The physician's responsibility is to follow your local policy whenever appropriate.

That's really sound advice, especially given the implications of this exam. So listen, thank you so much to both of you, Doctors Fisher and Kirshen, for your efforts in putting together this guideline and disseminating the education surrounding it. And more importantly, spending part of your day with me and our listeners and discussing

what can be a very challenging part of critical care practice. I will emphasize that those two documents, neurology and critical care medicine, are very well worth reading, very well laid out, and we will include those in the show notes. But until then, thank you again. I appreciate your time and I'm sure this will be very useful to our listeners. Thank you. Thanks for having us. Thanks, Seth. That wraps up another episode of Brought to you by the Educational Resources.

Of the Eastern Association. Educational and Networking and career development. Remember.