Secondary prevention entailed avoiding a second injury or the reoccurrence of the same or similar injuries. The issue of secondary prevention arose in the case of Mario, the patient with severe TBI. For athletes who feel the pressure to return to play before completely recovering from a concussion, second impact syndrome (SIS) can be their fate. Today, the entire sports medicine world is involved in preventing SIS, and clinicians have become sensitive to this issue. Experiencing a second injury before the brain fully recovers can cause a devastating cascade of physiologic events that ultimately result in massive brain swelling with the death of critical brain cells (McCrory 2001, Prins 2013).
Neuroprotection through secondary prevention
| Image # 8 – Secondary prevention |
Secondary prevention measures are also utilized to prevent the worsening of a current injury, and this includes the administered treatment interventions. Whenever there is an injury, our most important early treatment goal should be aimed at preserving the brain hierarchical organization, utilizing various methods to allow for neuroprotection. This can be achieved by the timely implementation of interventions that prevent the death of nerve cells by reducing the impact of the cascade of negative physiological events that occur after brain injury.
Various measures can be implemented per emergency and on an ongoing basis to prevent further injury or to prevent the negative cascade of physiological events that occur in the brain following injury. These secondary prevention methods also include early rescue measures to prevent or reduce further injury. In the case of Mario, his friend removed him from the water to prevent drowning and then made the critical phone call to the emergency medical response team. The paramedics were the first medical responders; they instituted early life-saving measures to protect and preserve the brain cells and brain architecture important for maintaining the hierarchal organization of Mario’s brain.
Let us now examine the events as they transpired to provide secondary prevention and neuroprotection in the case of Mario.
The “first responder” in the field were paramedics, and they performed the following secondary prevention measures:
• Early intubation measures to ensure adequate oxygen going to the lungs
• Intravenous (IV) fluids to support his blood pressure
• The administration of life-saving medications to stop his seizures
Despite the early intervention by the first responders, the emergency medical management team in the trauma center, neurosurgical intervention and management in an ICU equipped to handle critically ill neurosurgical patients, and neuroprotection measures to restore cerebral blood flow and oxygen and manage the increased intracranial pressure, Mario’s brain function couldn’t be sufficiently restored. Without those measures, however, he would not be alive today.
Even with all the measures taken, Mario’s brain was severely disorganized with the functional disruption that rendered him to stay in an unconscious comatose state, as he was not responsive to the external or internal environment. When I first evaluated him some three months after the initial injury, his nervous system was disrupted to the degree that he could not maintain physiological homeostasis. Physiological homeostasis refers to the body systems working together in a balanced manner.
In neuroscience we say, “Time is brain,” and the faster we provide definitive intervention, the more likely we are to preserve nerve cells, thus preventing cell death. With the preservation of nerve cells, the likelihood of recovery and preservation of function and hierarchical organization significantly improve.
Understanding BHET? From head to tail…
FOR JUST AS long as I have practiced medicine as a neurologist, I have been involved in the evolution of the information technology industry in health care. I have run companies involved in software development, data center operations, and connectivity between data systems. Our computer engineers and programmers would often be surprised that as a neuroscientist, I could understand the inner workings of computers and use that understanding to help troubleshoot certain dysfunctional challenges at our data center. Based on my experience in the fields of computer science and neuroscience, I have realized that computer developers and designers must have understood the inner workings of the nervous system in order to design computers. Computers at their core have a hierarchical design and function in a similar manner to the nervous system.
Except for in the movies, the one thing computers do not possess, and humans do is a higher cortical function that we call emotions. Emotions are what make us human, and they include experiences such as falling in love, expressing certain forms of judgment, sadness, happiness, pain, and suffering. To understand how computers are set up and operated, what happens when things go awry, and how to fix them, computer scientists hierarchically organize the computer system in terms of “computer dimensions.” Example of computer dimensions include terms such as software (e.g., Microsoft Word), hardware (e.g., Dell Computer Hardware system), communication (Cisco routers), operating system (e.g., Microsoft \windows 2000), processors (computer microprocessors called chips), and storage (hard drive). Neuroscientists have ironically utilized the term “dimensions” in a similar manner to help understand the complexity of the human nervous system and its operation, what happens when there is injury, and how to treat the results of such injury. The concept of the Brain Hierarchical Evaluation and Treatment (BHET) method is based on nervous system dimensions. Here are just a few dimensions to compare and contrast the human nervous system and computer systems:
Table # 8 – Brain and computer systems
| Categories | Computers dimensions | Human nervous system dimensions |
| Input | Keyboard | Sensory system (touch, sight, hearing, etc.) |
| Processors | Micro-processors | Brain systems (frontal lobe processors – executive function) |
| Output | Printer or monitor | Motor function (moving an arm or leg) |
| On–off switches | Plus, and minus switch organization | Stimulation and inhibition switches |
| Operating system | Set of organized rules and systems that give instructions | Physiologic instructions of the nervous system |
| Language system | Codified systems to communicate | Codified system – humans utilize to communicate |
| Storage system | Hard drive | Memory storage system in the temporal lobes – hippocampus |
| Power system | Power supply | Mitochondria in each cell |
| Booting system | Computer power switch | Reticular activating system (wakes up and puts the brain to sleep) |
| Reporting system | Report generation for decision making | Report generation – systems that draw conclusions to make decisions |
Simply put, the BHET protocol is a way to evaluate and treat TBI/concussion based on the hierarchical organization of the nervous system, the changes that occur in such a hierarchy following injury, and the subsequent recovery process and treatment methods. A “head to tail” approach establishes the hierarchal organization that makes us human. Symbolically, structurally, and physiologically, the tail refers to the spinal cord, the lower portion of the brain, and all of the nerves that connect to the brain and spinal cord, carrying messages to (input) and from (output) the nervous system while