Traumatic Brain Injuries (TBI)

What Is a Traumatic Brain Injury?

A traumatic brain injury (TBI) is a type of brain injury caused by a hit to the head. Impacts of varying force can cause an injury; however, not all impacts damage the brain.

The degree of damage and disability will depend on several factors, including the force of the blow, whether the injury breaks the skull, and where on the head the impact occurred. The severity of TBIs is determined using the Glasgow Coma Scale, which considers the person’s ability to move, speak, and open their eyes. Scores range from 3 to 15 and are used to categorize the injury as mild, moderate, or severe.

The symptoms of a TBI are heavily dependent on the area of the brain that has been injured. Different areas of the brain are responsible for specific functions like speech, the ability to feel things on the skin, or vision. Some brain regions are more susceptible to injury, like the frontal cortex located at the front of the head and areas deep in the brain responsible for movement, posture, blood pressure and breathing rate, emotions, and memory. These include the basal ganglia, diencephalon, and hippocampus.

Are Traumatic Brain Injuries Common?

According to the Centers for Disease Control, in the United States alone, there are more than 200,000 hospitalizations annually due to TBIs, but this is likely an underestimate due to underreporting. A study published in Frontiers in Neurology reports approximately 55.5 million individuals are living with TBI-related disabilities. The incidence of TBIs varies based on many factors, including race and ethnicity, biological sex, and socioeconomic status.

According to the Centers for Disease Control and Prevention, men are 2.22 times more likely than women to have a TBI, with men accounting for about 59% of all TBI in the United States. Although men tend to sustain TBIs at a young age, women are more likely to have a TBI after 65 due to falls.

Types of Traumatic Brain Injuries

There are three main types of TBI: penetrating, non-penetrating or closed, and blast.

Penetrating

Penetrating TBIs occur when the skull and protective membrane of the brain, the dura mater, are broken and torn. The most common cause of penetrating TBIs is gunshot wounds. Other causes include:

• Falls
• Stabbings
• Accidents involving sharp or hard objects that can break the skull

Penetrating TBIs are also called open TBIs because the brain is exposed through the skull. People with penetrating TBIs often have bleeding on the head and may have clear liquid (cerebrospinal fluid, the liquid that protects the brain inside the skull) leaking from the wound.

Non-Penetrating

Non-penetrating or closed TBIs result from an impact that rapidly moves the head, causing the brain to hit the inside of the skull. Motor vehicle accidents and falls are the most common causes of non-penetrating TBIs. Non-penetrating injuries also include those that are caused by diseases or conditions like heart attacks, strokes, infections, or tumors that can interrupt the blood supply to the brain or cause pressure in the brain.

Blast

Blast injuries are less common in the general population but are caused by blast waves from an explosion. The waves cause rapid changes in pressure in the skull, damaging brain cells and blood vessels. These are seen most often in military personnel in combat zones.

What Are the Symptoms of a Traumatic Brain Injury?

TBI symptoms vary significantly based on the degree and location of the damage.

Mild and Moderate Brain Injuries

Mild brain injuries commonly cause the following symptoms soon after the injury occurs:

• Headache
• Nausea and vomiting
• Dizziness
• Slurred speech
• Difficulty with balance or coordination
• Difficulty focusing

Many of the symptoms of a mild TBI may resolve on their own after a few weeks or months. Some of the symptoms that can last longer include:

• Vision changes
• Balance issues
• Sensitivity to light or sound
• Ringing in the ears
• Sleep issues
• Irritability
• Fatigue

Severe Brain injuries

Severe TBIs can cause problems breathing, maintaining appropriate blood pressure, unconsciousness, loss of memory, and issues with speech or sensation.

The most serious TBIs, like penetrating TBIs, can result in prolonged unconsciousness and severe disability that requires intensive daily medical care. As with mild or moderate TBIs, some recovery is possible but is difficult to predict because every injury is unique.

What Are Complications of Traumatic Brain Injuries?

Traumatic brain injuries can be clinically complicated because the brain controls nearly all bodily functions. After an injury occurs, secondary symptoms may develop as the brain attempts to re-establish stability. In mild TBI, sleep disorders and mental health issues, including depression and anxiety, are common. The following complications can also develop:

• Ventilator-associated pneumonia: People with severe TBIs can be put on mechanical ventilation or a respirator to assist with breathing. Up to 30% of people in this situation develop ventilator-associated pneumonia.
• Intracranial hypertension: Blood pressure changes after a TBI can cause pressure to increase in the brain. This pressure can cause secondary brain injury and is managed by medicines that reduce blood pressure.
• Acute kidney injury: About 10% of people with severe TBIs will develop kidney injury. This complication is associated with longer hospital stays and breathing assistance (tracheostomy).
• Trauma-induced coagulopathy: Difficulty with clotting occurs in approximately 25% of people with severe TBIs, especially those caused by motor vehicle accidents.

These complications are most commonly associated with severe TBIs.

How Are Traumatic Brain Injuries Diagnosed?

TBIs are diagnosed using a combination of function testing and imaging. A healthcare provider will initially evaluate whether the person can speak, open their eyes, and move. Other cognitive tests may also be performed. Function is scored on the Glasgow Coma Scale, with higher numerical values indicating more severe impairment.

Imaging tests are important to determine what in the brain has been damaged. These tests often include:

• Computerized tomography (CT) scans can show bleeding or bruising as well as other damage to brain cells.
• Magnetic resonance imaging (MRI) produces more detail about injured tissue. Because MRIs take longer to evaluate than CT scans, they are typically used in longer-term follow-up exams.

What Are Treatments for a Traumatic Brain Injury?

Mild TBIs, like concussions, are not typically treated, but a healthcare provider may recommend rest and refraining from using electronics, such as computers and televisions. These recommendations aim to allow the brain to heal as much as possible and are highly successful in preventing long-term symptoms. Over-the-counter pain relievers may be taken for symptoms like headache.

When a more severe TBI is suspected due to a motor vehicle accident or a gunshot wound, treatment is focused on stabilizing the person to reduce the risk of oxygen deprivation and blood loss.

Medicines are often administered, including:

• Anticoagulants to prevent blood clots
• Anticonvulsants to prevent seizures
• Diuretics to reduce the amount of fluid in the blood that can increase pressure in the brain

Other medicines that may be given to a person with a TBI are muscle relaxants and anti-anxiety medications.

Longer-term treatments focus on improving the person’s independence, as people with TBIs may also need to relearn skills. Rehabilitation may include physical and occupational therapy, cognitive therapy to improve memory and attention, and speech therapy to help people regain communication.

People with severe TBIs may experience permanent disability that requires home care services to help with activities of daily living, like bathing, cooking, cleaning, and managing finances.

Can You Fully Recover from a Traumatic Brain Injury?

Fortunately, the brain has an amazing ability to adapt after mild injuries. Still, it’s important to follow all recommendations from a healthcare provider to maximize recovery after a mild TBI. Recovery takes time, so patience and rest are critical after a mild injury.

With the assistance of longer-term therapies, people with more severe injuries can also see improvements over time.

Can Traumatic Brain Injuries Be Prevented?

The risk of traumatic brain injury can be reduced by:

• Using protective equipment for sports
• Wearing a seat belt in motor vehicles
• Taking measures like utilizing grab bars in bathtubs and handrails for stairs to prevent falls, especially for older adults
• Avoiding the use of illicit drugs or alcohol when operating a motor vehicle

While these factors can reduce the chances of having a TBI, they can’t fully prevent one from happening.

When Should People With a Traumatic Brain Injury Go to the Emergency Room?

You should go to the emergency room if you have sustained a head injury and experience headache or vomiting or have difficulty staying awake. Other symptoms that signal an issue are when one pupil of the eye is larger than the other, a seizure occurs, or coordination problems develop. TBI warning signs can be subtle, so when in doubt, you should go to the emergency room, as early diagnosis and treatment can be beneficial to recovery.

What Questions Should I Ask My Healthcare Provider?

If you have experienced a head injury, information from your healthcare provider can help improve your clinical outcomes. Here are some questions that might be helpful to ask:

• What kind of injury do I have?
• What kinds of symptoms should I expect, and for how long?
• What medicines are safe to take while I recover?
• What kinds of activities are safe while I recover?
• Should someone stay with me?
• When can I return to work?

Depending on your symptoms, it may be helpful to have a loved one with you while at the doctor’s office.

Navigating Injury and Recovery

If you or a loved one has experienced a TBI and are on the road to recovery, there are steps you can take to support your healing journey.

Following treatment recommendations, being aware of changing symptoms, and communicating with healthcare providers can all help maximize recovery.