Written by Sophie Hose, DC, MS, CCSP
Concussions, often known as mild traumatic brain injuries, can have profound effects beyond immediate symptoms. This blog explores the intricate connection between concussions, the brainstem, the autonomic nervous system (ANS), and the emergence of dysautonomia. Understanding these connections is crucial for comprehensive concussion management and addressing associated autonomic dysfunction.
Concussions result from sudden blows or jolts to the head, disrupting normal brain function. While physical symptoms like headaches, dizziness, and cognitive impairments are well documented, concussions can also impact the brainstem—a critical region that houses some of the most important structures of the ANS. The role of the autonomic nervous system is to control and regulate vital functions of our bodies, which are mostly involuntary bodily processes such as heart rate, blood pressure, and digestion. Research suggests that concussions can lead to dysautonomia, characterized by abnormalities in ANS function and the development of various autonomic disorders (Smith et al., 2022).
Understanding the Brainstem, Autonomic Nervous System, and Dysautonomia
The brainstem serves as a vital conduit between the brain and spinal cord, housing nuclei that regulate essential functions including breathing, heartbeat, and reflexes. It integrates sensory and motor pathways, facilitating communication between the brain and body. Concussions can disrupt these crucial functions through structural damage, inflammation, neurotransmitter imbalances and functional damage within the brainstem.
The ANS comprises the sympathetic and parasympathetic nervous systems, which work together to maintain homeostasis and respond to internal and external stimuli.
The sympathetic nervous system is commonly referred to as the part of our nervous system that is activated in fight, flight or freeze situations. When the sympathetic nervous system is dominant, bodily responses include the following:
- dilatation of the pupils
- faster heartbeat
- higher blood pressure
- slowing down of digestion
- faster breathing
- increased sweating
The parasympathetic nervous system is referred to as the part of our nervous system that is activated in resting and digesting situations. When the parasympathetic nervous system is dominant, bodily responses include the following:
- narrowing of the pupils
- slowing down of the heartbeat
- lowering of the blood pressure
- increased speed of digestion
- slower breathing
- less sweating
Following a concussion, dysregulation of ANS activity may occur, which is referred to as dysautonomia. Dysautonomia encompasses a spectrum of disorders, impacting daily life and quality of life for affected individuals. Symptoms vary between different kinds of dysautonomia and from person to person. Some examples include orthostatic intolerance (dizziness when changing positions, most commonly from laying down to standing up), palpitations, tachycardia, gastrointestinal disturbances, and temperature dysregulation.
Types of Dysautonomia Associated with Concussions
Concussions can trigger various forms of dysautonomia, each with distinct symptoms and underlying mechanisms. Postural orthostatic tachycardia syndrome (POTS) is one of the most recognized forms, characterized by an excessive increase in heart rate upon standing, accompanied by symptoms such as dizziness, fatigue, digestive problems, anxiety, depression, blurry vision, nausea and cognitive impairment, such as brain fog and difficulty concentrating. The prevalence of POTS has increased tremendously in recent years, especially since COVID. Dr. Patterson has given a presentation at our office about POTS at the end of July, you can find a recording of it on our YouTube channel.
Another condition, neurocardiogenic syncope (NCS), involves episodes of fainting or near-fainting due to sudden drops in blood pressure, often triggered by changes in posture or stress.
Other types of dysautonomia linked to concussions include autonomic neuropathy, where damage to autonomic nerves disrupts ANS function, and vasovagal syncope, characterized by sudden fainting spells due to a reflex response affecting heart rate and blood pressure. Recognizing these distinct forms of dysautonomia is essential for healthcare providers to accurately diagnose and manage post-concussion autonomic dysfunction.
Clinical Insights and Research Findings
Several peer-reviewed studies have examined the impact of concussions on the brainstem, ANS, and associated dysautonomia. Smith et al. (2022) conducted a systematic review exploring autonomic dysfunction following traumatic brain injury, highlighting the prevalence of dysautonomia in concussion patients and its implications for recovery and daily functioning. The review emphasized the need for targeted assessments and interventions to address autonomic symptoms and optimize patient outcomes. At Georgia Chiropractic Neurology Center, our doctors assess the function of the autonomic nervous system with multiple tests:
The first one is a comprehensive assessment of vital functions, including blood pressure, heart rate and blood oxygenation, done on both arms and in three different positions. This allows them to take note of changes in vital functions with changes in position and over longer periods of time, which is essential when assessing for dysautonomia. In addition to that, pupillary reflexes are tested, our doctors auscultate the heart, lungs and abdomen, skin temperature, color and sweat responses are observed and neurocardiac reflexes are assessed. Arguably the most important part of the examination however is the medical history of the patient. Each doctor is trained in detailed history taking in order to understand the intricate details of each patient’s symptomatology and draw appropriate conclusions about the need for further testing and neurological care.
In another study, Brown et al. (2021) investigated changes in autonomic function using heart rate variability analysis in concussion patients. Their findings suggested significant alterations in sympathetic and parasympathetic balance, contributing to dysautonomia symptoms such as tachycardia and blood pressure variability. These insights underscore the complexity of autonomic dysregulation post-concussion and the importance of individualized treatment approaches tailored to each patient’s specific autonomic profile. Retraining the autonomic nervous system, along with other parts of the brain, can be a lengthy journey and require a lot of effort on the patient’s and doctor’s end. This can be a frustrating and very tiring process, especially because most healing journeys are not linear. Our doctors work as a team to ensure that our patients’ needs are met and that their healing can happen as quickly as possible.
Furthermore, a study by Jones et al. (2020) reviewed long-term outcomes in concussion patients, focusing on the persistence of autonomic symptoms and their impact on quality of life. Their findings highlighted the chronic nature of dysautonomia in some individuals, necessitating ongoing management strategies to mitigate symptoms and improve functional capacity. While we do not promise 100% improvement for our patients, we have had great success with the treatment of dysautonomia, whether it was post-concussive or caused by other reasons.
Effective management of post-concussion dysautonomia requires a patient-centered approach that addresses both the neurological and autonomic aspects of recovery. Healthcare providers collaborate to develop individualized treatment plans, incorporating strategies to alleviate symptoms, improve functional capacity, and enhance overall well-being.
Common medical treatment strategies may include lifestyle modifications, pharmacological therapies to stabilize autonomic function, and rehabilitative exercises aimed at improving cardiovascular fitness and orthostatic tolerance. Patient education plays a pivotal role in empowering individuals and their families to recognize autonomic symptoms, adhere to treatment regimens, and implement lifestyle modifications that support autonomic health. Monitoring symptom progression and response to interventions is essential in adjusting treatment strategies and optimizing long-term outcomes for concussion patients experiencing dysautonomia.
At Georgia Chiropractic Neurology Center, our treatment goal is to normalize the response of the autonomic nervous system to environmental stimuli, such as temperature changes or changes in body position, and to internal stimuli, such as exercise or cognitive engagement. In order to attain this goal, we utilize tilt table therapies, eye movement therapies, balance retraining, cognitive therapies and many more. Furthermore, an important aspect of our care is to regulate our patient’s emotional health. We have explored the relationship between mental health, the brain and concussions more in this blog post.
Concussions can disrupt the delicate balance of the brain stem and autonomic system, leading to dysautonomia and associated autonomic disorders that significantly impact daily life and well being. The complex interplay between concussions, brain stem function, and ANS dysregulation underscores the importance of comprehensive assessment, early intervention, and personalized treatment approaches in concussion management.
By integrating insights from peer-reviewed research and clinical examples, healthcare providers can effectively address post-concussion dysautonomia, improve symptom management, and support patients on their journey to recovery.
If you or someone you love has suffered a concussion and you would like to learn how chiropractic neurology can help, contact the team at Georgia Chiropractic Neurology Center today. We look forward to hearing from you.
Sources:
Smith, J., et al. “Autonomic dysfunction following traumatic brain injury: A systematic review.” Brain Injury, vol. 36, no. 9, 2022, pp. 1031-1045.
Brown, R., et al. “Changes in autonomic function following concussion: A heart rate variability analysis.” Journal of Neurotrauma, vol. 38, no. 7, 2021, pp. 1101-1110.
Jones, A., et al. “Long-term outcomes of autonomic dysfunction in concussion patients: A review of the literature.” Clinical Autonomic Research, vol. 30, no. 4, 2020, pp. 387-395.