Intro: Welcome to UAB MedCast, a continuing education podcast for medical professionals. Providing knowledge that is moving medicine forward. Here's Melanie Cole.

Melanie Cole, MS (Host): Welcome to UAB MedCast. I'm Melanie Cole. And today, our discussion focuses on disorders of consciousness. Joining me is Dr. Rachel Teranishi. She's a Physical Medicine and Rehabilitation specialist with a focus on Brain Injury Medicine. And she's an Assistant Professor at UAB Medicine.

Dr. Teranishi, thank you so much for joining us today. This is a really interesting topic and not one that gets talked about that much. So, why don't you start by setting the table for us. What are disorders of consciousness and how prevalent are these?

Dr. Rachel Teranishi: Hey, thank you so much for having me today. Disorders of consciousness, or DOC as we abbreviate, in very simple terms are individuals who have impaired consciousness. Consciousness can be defined as being both awake and aware. So, a DOC patient has some problem in one or both. DOC patients include those in a coma, a vegetative state, also known as an unresponsive wakefulness syndrome or UWS or a minimally conscious state, sometimes called MCS. Different types of neurological disorders may cause DOC, such as non-traumatic injury like stroke or anoxic brain injury.

However, for the purposes of this talk, I'm really going to be focusing mostly on the traumatic brain injury or TBI. As patients recover from their injury, they usually go through several stages of recovery, from coma to vegetative state, to minimally conscious, to confusional state. Recovery through these phases can be fast, slow, or stop, and some patients may not transition sequentially.

Coma is usually a self-limited stage, and vegetative state or UWS is typically considered chronic after 12 months after a TBI or three months after a non-traumatic brain injury. As many providers are probably aware, coma is defined as a lack of sleep-wake cycle, which returns in the vegetative state.

Minimally conscious, as the name suggests, means that there is some consciousness, but it's minimal and inconsistent. Usually when an MCS patient can demonstrate functional communication or functional object use, such as showing how to use a comb, we say they have emerged and then they enter the confusional state and go through even more stages of recovery.

In terms of the pathophysiology of DOC, there are a lot of complex pathways involved. The reticular activating system and the brainstem is important for arousal, and the cortico-thalamic system is very important in consciousness. As you can imagine, people in a DOC typically have quite severe injuries and they're at high risk for medical complications such as infection, dysautonomia, hydrocephalus, and neuromuscular dysfunction.

Melanie Cole, MS: Well, that was a comprehensive answer. Thank you so much. So as we think of assessing patients with disorders of consciousness, and given the complexities in diagnosing these, how have recent advancements in neuroimaging techniques and other advancements influenced diagnostic accuracy and treatment strategies? Tell us about assessment.

Dr. Rachel Teranishi: Not surprisingly, it's really hard to assess and properly diagnose these patients. There are also really high rates of misdiagnosis, which is usually around 40%. There are a lot of interest in different diagnostic tools like you mentioned, but there are a lot of challenges and limitations to those. So, really, behavioral assessment is actually the gold standard for diagnosis. Experts recommend using standardized assessment measures that are valid and reliable to improve the accuracy of diagnosis.

One specific example that we use a lot is something called the coma recovery scale or CRS, and it organizes consciousness into different categories, and it's a great protocol with specific details on how to elicit some of those responses and what to look for. So, for example, when you're looking at visual function and visual fixation, you're supposed to present an object in front of their face and move it in four different directions on four trials, and observe fixation on the object for at least two of the four trials. The CRS assigns a score to each section and then gives information on how significant that score is.

So going back to that visual function example, if you're looking for fixation, you get two points for that, and that means that somebody is actually in a minimally conscious state compared to a coma or unresponsive wakefulness syndrome. Compared to something a little bit less advanced, such as just visual startle, that's only one point, and that does not denote that they're in a minimally conscious state.

So for these patients, because they can't communicate normally and they're not following commands, it's really hard to assess them. But there can be those subtle signs of consciousness that can be picked up on that exam. Of course, it's helpful to do serial exams for these patients sometimes at different times of the day because their exam and their consciousness can really fluctuate.

Going back to the original question about some of the other technology, there's a lot of interest in things like functional MRI, transcranial magnetic stimulation, and I think there's a lot of promise. However, there's still a lot that's unknown about the diagnostic utility of those specifically in distinguishing minimally conscious from unresponsive or vegetative state.

There's lots of other tools that we still use though, such as a structural MRI and EEG. Those are also very important. We use them to obtain more information and potentially aid in prognosis. And as you can imagine, this diagnosis is a really important step, because IT affects the overall prognosis. And the consciousness, like I said, can really be easily missed if we're not taking the time to evaluate these patients.

Melanie Cole, MS: Well then, let's talk about treatment strategies and in the context of long-term care and rehabilitation, tell us about interdisciplinary, multidisciplinary approaches that have shown the most promising results for these patients. What do you do for them?

Dr. Rachel Teranishi: There are a lot of things we still don't know about this population, but there's a lot of research interest in DOC patients and there have been some helpful guidelines that have been developed. In particular, there's this practice guideline update that was created with different organizations, including groups from Neurology and Rehabilitation Medicine. And it was really cool to see this guideline because it's different specialties coming together and creating a standardized approach for these individuals.

There were a lot of big takeaways from that article, but one big one, as you alluded to, is that these individuals really benefit from specialized multidisciplinary care, including things like Speech Therapy, Physical Therapy, Occupational Therapy, Neuropsychology, Rehab, Nursing, you name it. And each discipline really has an important role in assessing these patients. So, Speech Therapy, a lot of time, is administering the CRS scale, looking for those signs of arousal. Physical Therapy is looking at cardiovascular status and their response to different mobility, occupational therapies, looking at range of motion. So, every discipline really has an important role in taking care of these patients. And of course, early on, right after their injury, their treatment is more directed at some of the acute complications such as providing respiratory support and things like that. So, multidisciplinary is very important for these patients and the care of them.

Other things that I did want to mention are there a lot of medications and different things that we can use. A lot of research going into those different options. Particularly for arousal, there was a really good medicine called amantadine. It was in a New England Journal of Medicine article. And amantadine was typically used as a Parkinson medication, but it found in severe TBI patients, it actually sped up the recovery of these patients. So in the study, there were almost 200 people enrolled four to 16 weeks from their injury, and they were randomly assigned to receive the amantadine or the placebo. They looked at some outcome scores and they found that both groups improved. But the amantadine group recovered significantly faster, thought to be related to the way that it works on dopamine in the brain. And beyond that, there's a bunch of other cool things that we can look at. There's some interest in neuromodulation techniques such as deep brain stimulation. So, I think there's a lot of promise for treatment for this population in the future.

Melanie Cole, MS: It's fascinating. Really mysterious and fascinating as well. And, Doctor, what about the patient's family and their loved ones? You're speaking to other providers. Give them some practical advice about what's happening with their loved one at this time, what we know to tell them to help ease what must be a very traumatic time in a family's life.

Dr. Rachel Teranishi: As always, there should be attention to stage of recovering time since injury, since advice will really need to be tailored to those things. And we always need to assess what information families want to hear and are prepared to hear. Generally starting with something simple like just educating them on the diagnosis and the stage of recovery, that's a good place to start. So, explaining the level of consciousness in very simple terms can be helpful for the family to hear. For example, somebody who is in a vegetative state or unresponsive wakefulness syndrome can be summarized as having generalized responses. So, I tell them what that means, things they might be seeing, such as waking up to a noise, grimacing in response to pain, or spontaneously moving their extremities. And I go over all that with the family.

The guidelines that I mentioned earlier also report level A evidence that clinicians should avoid statements of universally poor prognosis within the first 28 days. Prognosis discussions are always challenging. Of course, we need to communicate the seriousness of the diagnosis. So, that recommendation does not mean we're supposed to avoid prognosis discussions altogether, just to be aware that there's a lot unknown at this stage in their injury. And I'll go over some of that data and the reasons for that recommendation a little bit later.

But we provide a lot of education on ways to interact with these individuals too, while trying to avoid overstimulation. So, some very specific suggestions I give to families is things like avoid talking on the phone loudly near the patient, or having too many visitors at once since the disorders of consciousness patient can't say, "Hey, I'm getting overstimulated." We really counsel them on things to look out for, such as sweating, teeth grinding, restlessness, or agitation. We also tell families to give more time than they usually would for the patient to respond to commands. Offer one direction at a time instead of just a rapid fire of questions and commands.

Families are really encouraged to say who they are each day when they see the patient. Hang pictures of friends and family and keep a notebook. UAB actually has a lot of great resources and fact sheets on our website tailored towards family education because it can be an overwhelming amount of information for people. So, it includes a lot of education on DOC, but also resources for less severe injuries. And that website can actually be found from the uabmedicine.org page if you search for traumatic brain injury. So, that's a resource and a tool that other providers can really use.

Melanie Cole, MS: This is great information and so informative. As we get ready to wrap up, what do we know about the functional outcomes of these patients? And if you'd like to mention any emerging therapies or technologies that show promise in improving outcomes for patients and the implications for clinical practice, what would you like other providers to have as the key takeaways of this episode today?

Dr. Rachel Teranishi: There's a lot that we are still learning about the long-term outcomes of these individuals. As you can imagine, some individuals do not recover as well. Mortality rates can be quite high. Usually, those are associated with withdrawal of life-sustaining therapy. And there are certain individuals, like I mentioned earlier, that may not ever progress beyond certain stages of the recovery. But there are a lot of studies showing significant potential for recovery, and that's one thing that I really want to stick with other providers as we're ending the discussion today.

So, one study was looking at DOC patients admitted to inpatient rehab, and they found that 20% of those were actually able to become functionally independent, meaning they're walking, getting dressed on their own and actually able to return to work in some capacity at one or more followup intervals being one, two, and five years.

There was another study looking at individuals with DOC. And they found that almost half of them recovered to a level of daytime independence at home. So, these studies are really cool because they're looking at long-term outcomes and they really demonstrate the potential for recovery as well as the duration that recovery may occur.

While some patients may plateau earlier than others, there are some that are recovering for several years after their injury. Again, the road to recovery is challenging for some of these patients, even if they have a good outcome. So again, we still want to properly educate people on the severity of their diagnosis.

But this is the reason for that level A evidence that I mentioned previously. Not only do some of these severely injured patients get better, but some of them actually get to the level of being able to live independently, work and drive. And this is really the main reason why I enjoy working with this population so much and why my colleagues and I at Spain Rehab are so passionate about the field of brain injury.

Melanie Cole, MS: Beautifully said. So compassionate, Dr. Teranishi. I can really hear that in your voice for these patients. And thank you so much for joining us today and sharing your incredible expertise. For other providers and for more information, please visit our website at uabmedicine.org/physician. That concludes this episode of UAB MedCast. I'm Melanie Cole.