What is Post-Concussive Dysautonomia?

Jul 28

Post-concussive dysautonomia is a disorder that involves dysfunction of the autonomic nervous system, or ANS, following a concussion or traumatic brain injury (TBI) (1). The autonomic system regulates critical involuntary bodily functions including heart rate, blood pressure, breathing, digestion, and a number of other reflexes that are critical to survival. Dysautonomia makes it challenging to regulate the autonomic responses needed to compensate for a postural change.

How Common is Post-Concussive Dysautonomia?

Concussions affect 1.8-3.8 million people annually and are likely underreported. As for post-concussive dysautonomia, it is not a well-recognized condition and is also severely underreported, despite being extremely common (16).

What Causes Post-Concussive Dysautonomia?

Post-concussive dysautonomia is caused as a result of the body's diminished ability to regulate proper blood volume through the, body through the changing of positions. What causes this lack of regulation is different in each case, and some people have multiple contributing factors. It is important that each individual living with post-concussive dysautonomia receives a thorough neurological assessment, as the correct treatment differs depending on the cause.

Regulation of the ANS involves several brain regions, including the cortical, subcortical and brainstem regions. Specific cortical regions, including the insular and medial prefrontal cortex, the amygdala, hypothalamus and brainstem regions have all been recognized as being important to the control of the autonomic nervous system (1). We also utilize the vestibular system in our inner ear to inform our brain of our head’s position relative to our body. This information travels to our brainstem where it needs to integrate with information from our cortex about where we are in space in order to signal to our blood vessels that they need to constrict and send blood to our brain (4). Dysfunction in one or multiple systems involved in this complex orchestration can lead to post-concussive dysautonomia.

What are the Symptoms of Post-Concussive Dysautonomia?

Symptoms of post-concussive dysautonomia differ from person to person. They may include any of the following constellation of symptoms: severe and long-lasting fatigue, sleep disturbances, lightheadedness or dizziness when changing posture, fainting, nausea, vomiting, headaches, “brain-fog” (thought and focus difficulties), excessive sweating, increased muscle tone in the neck or flexor muscles, sensation of powerful or irregular heartbeats, and pale face/discolored hands and feet.

Not all patients will have all symptoms, and not all symptoms listed are the only symptoms of Post-concussive dysautonomia. However, often post-concussive dysautonomia patients will have increased symptoms present when they are in warm environments (such as a hot shower), when they have decreased water intake, when they have increased salt intake or they have been standing for an extended period of time (3.

What Happens in the Brain with Post-Concussive Dysautonomia?

When someone goes from lying to standing, gravity pulls blood down towards their feet. The autonomic system needs to tell blood vessels to constrict, so that blood can be pumped back up to the brain. These reflexes work poorly in dysautonomia, and blood flow to the brain subsequently decreases.

The brain will normally increase the heart rate to compensate for this blood pressure drop. In some types of dysautonomia, the increase in heart rate is extreme, and thus the heart will beat before it has a chance to properly fill with blood. This leads to even less blood flow to the brain. These patients will suffer dizziness, often will faint, and frequently are injured as a result of these falls. Others may experience constant headaches, brain fog, light and sound sensitivity or lightheadedness as a consequence of their dysautonomia. The literature also demonstrates that consistently increased blood pressure and demand on the sympathetic nervous system can cause damage to the organs that process blood, such as the heart and kidneys (2).

When the brain does not receive sufficient blood flow, myriad symptoms may present. Your brain requires a great deal of energy to function properly, and when this is disrupted, a host of brain functions are disrupted. Simple cognitive tasks become profound challenges, simple physical tasks become exhausting. Emotional regulation can become extremely difficult. Everything your brain does depends on the ability to properly regulate blood flow. When this fails, virtually everything your brain attempts to do can become a struggle (3).

How is Post-Concussive Dysautonomia Usually Treated?

There is no known established cure for post-concussive dysautonomia. Most cases are treated through lifestyle changes, diet, and physical exercise (8,9). For some patients, medications that cause your kidneys to retain salt and thus increase blood volume are deemed appropriate. In other cases, medications that suppress the sympathetic nervous system output are prescribed. While these can help mitigate some of the symptoms of post-concussive dysautonomia, they generally do little to affect the impaired autonomic reflexes that are the underlying cause of the disorder (16).

How is the NeuroRescue Program Different?

One of the main things your brain does, and maybe even the primary thing, is help you determine where you are in the world. Your brain uses inputs from your inner ear to figure out where your head is in relation to gravity and how it is moving. It uses inputs from your muscles and joints to figure out where your body is in relation to your head and what your body is doing. It uses inputs from your eyes to figure out where your body is in relation to the visual environment.

Your brain needs to put all of that together to make sense of where the world is, and where you are in relation to the world. It needs to be able to localize you effectively in the environment, in order for you to be able to respond to the environment properly.

Your brain organizes all of this information in terms of maps. There is a vestibular map from the inner ear, a proprioceptive map from muscles and joints, a vascular map of your blood flow, a visual map of the world from your eyes, and several others. Your brain needs these maps to be saying largely the same thing about where you are in the world at all times.

One often overlooked feature of post-concussive dysautonomia is that these maps usually fail to match. Your eyes, inner ear, and muscles are creating maps that say different things about where your head is in relation to gravity. When you go from lying down to sitting up or standing, problems in these maps can make it difficult for the brain to compensate for the postural shift.

If the brain does not understand the position of the head in relation to gravity, it cannot properly control the vascular system to send the appropriate amount of blood to the head (3). We utilize eye movements to activate the various cortical, subcortical and brainstem regions involved in the ANS to improve function and connectivity (10).

This is why many patients fail to fully resolve their post-concussive dysautonomia with most forms of treatment. Without addressing the problems in these maps, it will remain impossible for the brain to properly control blood flow, and the best they can hope for is to gain some control over their symptoms. We would much rather try to address the underlying cause.

How does the NeuroRescue Program work?

We design your unique NeuroRescue Program to be among the most comprehensive diagnostic and therapeutic protocols available today. We create individual NeuroRescue Programs based on a comprehensive analysis of every relevant neurological system and pathway, using gold-standard, cutting edge neurodiagnostic technologies and examination procedures and state-of-the-art therapies.

We begin with your Discovery Day, wherein we perform a comprehensive history of not only your condition, but your life on a timeline. This allows us to dive deeply into your case and see all of the factors that led to where you are now. It helps us uncover hidden problems and associated conditions that may be making it difficult for you to move your recovery forward.

Our examination allows us to identify the areas and pathways of your brain that have been impacted by your injury. We begin by precisely quantifying the function of your visual, vestibular, and proprioceptive systems through computerized analysis of your eye movements, your inner ear reflexes, and your balance in a host of different sensory conditions.

We employ technologies including Videooculography and Saccadometry to measure several classes of eye movements. We use Video Head Impulse Testing to measure the function of your inner ear, and Computerized Dynamic Posturography to assess your balance in different sensory conditions.

We use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and perception of vertical in a virtual reality environment.

We combine all of this with a comprehensive physical and neurological examination of your sensory, motor, autonomic, and cognitive systems. We also perform a passive tilt table test (7). We review any relevant laboratory testing, radiological imaging, and prior neurodiagnostic testing, and integrate that information with our findings.

We use this information to identify which parts of your brain are working properly, which systems are struggling, and the precise point at which your systems fatigue.

We can then design a NeuroRescue Program that is unique and specific to your brain, and yours alone. Your NeuroRescue Program works to rejuvenate and reintegrate the damaged neurons and pathways in your brain. It works to improve energy, endurance, and functional capacity within your fragile systems.

Our therapies may range from specific eye exercises (11), to specific types of vestibular therapy (12), to unique forms of electrical stimulation (13). We may employ laser and LED photobiomodulation (14), or even exercises in a virtual reality environment (15). All of our therapies will be specific to your unique case, based purely on your neurodiagnostic testing data and examination findings.

We use our technologies and procedures to not only see what we need to address, but also when it is time to stop and let you rest. We address your impaired neurological function from multiple angles of therapy, and provide metabolic support to improve neurological recovery.

While we cannot bring back neurons that have been lost, your NeuroRescue Program allows us to take the pathways that remain and maximize their efficiency and endurance. And by focusing on the integration of systems, we can do more than just get pathways working better, we can get them working together again. This gives us our best opportunity to get your dysautonomia under control, and return you to living a healthy, vibrant, and fulfilling life.