What Is a Traumatic Brain Injury?
There’s a lot of confusing vocabulary to describe traumatic brain injuries. To be sure we’re on the same page in this article, we’ll define some terms that are commonly used to describe TBIs, what causes them, and how we evaluate their severity.
Defining Traumatic Brain Injury
A traumatic brain injury is brain dysfunction caused by an outside source. Very simply: damage occurs to the brain, and the brain doesn’t function normally after that.
We refer to a brain injury caused by an outside source as an acquired brain injury, meaning it happens after birth. To be clear, there are other scenarios that can result in brain damage that don’t come from an outside source. A non-acquired brain injury is a brain injury caused by genetic or hereditary factors, birth trauma, or from a degenerative cause, such as Alzheimer’s disease or Parkinson’s disease.
The medical community further divides the term “acquired brain injury” into the terms “traumatic” and “non-traumatic” acquired brain injuries for clarity. A traumatic brain injury is the result of some kind of outside force, such as an object hitting the head. A non-traumatic brain injury is the result of a “closed head injury,” such as a stroke.
We don’t like the term “non-traumatic” because it implies the injury and its consequences are somehow less frightening and distressing than a traumatic injury. Either kind of brain injury is traumatic to the person experiencing it, and they can both result in the same unpleasant, long-term symptoms.
Note for the curious: The medical use of the word “traumatic” comes from the definition of trauma meaning, “a serious injury to a person’s body,” not the one meaning, “a very difficult or unpleasant experience that causes someone to have mental or emotional problems usually for a long time.” This is why blunt injuries are described as “traumatic,” even though an injury like a stroke would also be distressing.
When we refer to TBIs in this article, we’re talking about both “traumatic” and “non-traumatic” acquired brain injuries.
What Causes Traumatic Brain Injury?
Traumatic brain injuries (TBIs) have been on the increase since 2006 according to the Centers for Disease Control and Prevention (CDC). The CDC reported 2.53 million emergency department (ED) visits and 56,800 deaths related to TBI in the year 2014 alone. That’s a staggering number of brain injuries, and it doesn’t even include mild traumatic brain injuries (mTBI), commonly known as concussions, that didn’t result in a trip to the ED.
The majority of traumatic brain injuries are labeled as “mild concussions” that will hopefully resolve within a week or two of the injury. Moderate to severe TBIs might require hospitalization, surgery, and rehabilitation.
Most of our patients at Cognitive FX have suffered from long-term problems from a traumatic brain injury, but we can treat those with non-traumatic brain injuries as well.
Sources of Traumatic Brain Injuries
A traumatic brain injury often happens because of a direct blow to the head, but it can result from any jarring movement that causes the brain to smash into the skull. Inflammation and swelling inside the brain often damage nerves and prevent areas of the brain from receiving the oxygen and glucose it needs to perform. These effects of the injury disrupt the normal function of the brain.
Some of the most common sources of traumatic brain injuries are falls, motor vehicle accidents, assault, and sporting accidents. Military service members have a fairly high rate of TBI. A TBI can even be a byproduct of a life-saving operation such as neurosurgery.
Sources of Non-Traumatic Brain Injuries
Non-traumatic brain injuries usually damage the brain by a lack of oxygen as a result of internal bleeding, clotting, or toxins, or as a result of pressure being placed on areas of the brain from a tumor. This results in damage or even death of brain tissue.
Common sources of non-traumatic brain injuries are stroke, aneurysm, and near-drowning.
Others that involve toxins include carbon monoxide poisoning, chemotherapy, and lead poisoning. Bacterial and viral infections (including COVID-19), meningitis and encephalitis, and similar conditions can also cause destructive inflammation.
Further reading: Treatment for chemo brain and Patient story: recovery from carbon monoxide poisoning and The long-lasting effects of transient ischemic attack & it’s treatment
Mild, Moderate, or Severe: Understanding How We Describe Brain Injuries
Traumatic brain injuries are usually categorized as mild, moderate, or severe. These terms don’t necessarily indicate the severity of what patients experience long-term as a result of a brain injury though. A “mild concussion” can still disable a person. Cognitive FX frequently treats patients who are unable to work or are homebound from their persistent concussion symptoms.
However, we can still explain how the medical community differentiates these brain injuries.
A mild traumatic brain injury is commonly called a concussion. Someone with an mTBI may or may not have lost consciousness, but if they did, it was for a very short time. (In fact, less than 10% of people with a concussion lose consciousness.) There is usually no bleeding in the brain and no skull fracture.
With a moderate traumatic brain injury, we might see a skull fracture, such as a fracture under the eye. There could be a visible sign of injury on the head. There might be a loss of consciousness with this injury (less than 24 hours in duration). Any bleeding is not life-threatening. A person with a moderate TBI might be kept under observation for a short time, but the injuries usually heal on their own. They don’t usually require surgery but may require follow-up at a neurology practice.
Someone with a severe traumatic brain injury must experience an extended loss of consciousness or even be in a coma. The skull may have a serious fracture, or some object might have penetrated it. Severe TBIs often require intensive care and emergency neurosurgery:
- A craniectomy removes a portion of the skull to relieve intracranial pressure on healthy areas of the brain due to bleeding or swelling in the brain.
- If there is a cerebrospinal fluid leak, surgery might be needed to install a shunt to drain the fluid or to repair the leak.
- Two types of bleeding within the brain after a TBI can be life threatening: epidural hematomas and subdural hematomas. Occasionally, these bleeds are small and don’t cause swelling. In this case, they can be watched and might not require surgery. However, if the bleed continues and causes swelling within or on the brain, emergency surgery is necessary. It is important to note that those 60 years of age and older have the highest death rate after experiencing a TBI. In this population, even a minor fall could cause lethal bleeding.
Again, just because an injury isn’t categorized as “severe” doesn’t mean it won’t have very serious and real consequences in your life.
What Are the Acute Signs of a Traumatic Brain Injury?
Sometimes it’s clear that someone has experienced a traumatic brain injury and needs to get to a hospital immediately. For example, if someone is bleeding and unconscious after a car accident or a fall from a ladder, we know to call emergency responders right away.
Very often, however, people are unsure. Depending on where you live and what medical coverage you have, visits to the emergency department are expensive; people don’t want to overreact. To make things even more confusing, sometimes a person seems fine right after an incident, but alarming symptoms develop over the next few hours or days.
While this list isn’t exhaustive, here are some guidelines to determine if someone might have a concussion or a moderate to severe brain injury. If you’re unsure about the severity of the injury, it’s best to get checked out by a medical professional.
Signs that it might be a concussion:
- Difficulty balancing or dizziness
- Blurry vision
- Confusion about where they are or what day it is
- Slowness in thinking or acting
- Neck pain
- Ringing in the ears
- Sensitivity to light or sound.
In addition to any sign of a concussion, signs of a moderate or severe TBI are:
- Alteration in consciousness
- Person becomes unresponsive
- Eyes aren’t tracking properly
- Pupils are dilated
- Convulsions or seizures
- Vomiting or nausea.
The Brain Injury Association of America reports that brain injuries are the leading cause of death and disability in children and teenagers.
Children’s brains are different from adults. Sometimes their injuries aren’t immediately evident, and children can’t always verbalize what they’re experiencing.
Additional signs of TBI in children are:
- Nausea and vomiting
- Being unresponsive or losing consciousness
- Being excessively sleepy
- Trouble walking or problems with balance
- Weakness on one side of the body
- Slurring their speech
- Blood or a clear fluid draining from the ears or nose.
Unfortunately, the damaging effects of a brain injury on a child might not be evident until later in life, so it’s important to get a possible injury checked out and treated by a health care provider if there’s any question.