Brain Injuries

What Are Brain Injuries?

Brain injuries are a type of head injury that specifically impacts the scalp, skull, brain, and underlying tissue or vasculature. A brain injury that is not hereditary, congenital, degenerative, or induced by birth trauma is referred to as an acquired brain injury (ABI).

ABIs fall under two categories—non-traumatic brain injury and traumatic brain injury (TBI). Non-traumatic brain injuries commonly describe injuries caused by internal factors, while TBIs arise from an external force. Also, a person can suffer a closed (non-penetrating) or open (penetrating) injury to the head, which refers to whether the skull was breached.

Head injuries can range from mild (e.g., a cut, a bump, or a contusion) to moderate to severe (e.g., a concussion, internal bleeding, a deep wound, a fractured skull, or brain damage). Closed injuries can exhibit similar severity as open injuries, and many factors must be considered. Injuries to the head are common and can result in disability and even death.

Types of Brain Injuries

Head injuries can be confined to a local area or be widespread, which will influence the damage caused such as metabolic changes or inflammation. They can affect the skull, the fluid within the skull, the blood vessels present in the brain, or the brain itself, resulting in bone fractures, swelling, bleeding, or nerve damage.

Skull Fractures

Skull fractures are cracks or breaks in the bones that form the skull and can affect one or more bones. They usually occur because of a direct blow to the head and fall into four categories, including:

Linear Skull Fractures

Linear skull fractures are the most common skull fractures. This occurs when the skull cracks but does not move its position. People who experience these might undergo a brief observation at the hospital and normally have a fast turnaround without the need for medical intervention.

Depressed Skull Fractures

Depressed skull fractures may occur with or without a cut in the scalp, resulting in part of the skull becoming sunken from the trauma. Surgical intervention might be required depending on the injury severity.

Diastatic Skull Fractures

Diastatic skull fractures occur along the suture lines, or areas between the bones in the head that fuse during childhood, on the skull. When these types of fractures occur, normal suture lines are enlarged. Newborns and older infants usually experience these types of fractures.

Basilar Skull Fractures

Basilar skull fractures are severe types of skull fractures, usually involving a break in the skull bone at the base. These fractures typically require close observation in the hospital.

Typically, most skull fractures do not require surgery and resolve on their own. However, some skull fractures will require observation and treatment to resolve.

Hematomas (Blood Clots)

Intracranial hematomas (ICH) occur within or around the brain. Their classifications are based on their location in the brain and can range from mild to severe to life-threatening head injuries. Intracranial hematomas include four types:

• An epidural hematoma occurs when a blood clot develops below the skull but above the protective covering of the brain, the dura. They are normally a result of a tear in select blood vessels that run under the skull and are associated with skull fractures.
• A subdural hematoma occurs when a blood clot develops below the skull, below the dura, but remains outside the brain. It can form from a tear in the blood vessels between the brain and the dura or a cut on the brain itself. It may be associated with skull fractures.
• A subarachnoid hemorrhage occurs when there is bleeding between the pia and arachnoid mater of the brain.
• Intracerebral hematoma, or contusion, occurs when the brain itself is injured, resulting in bruising and swelling around the impacted area. Their occurrence may occur with skull fractures or other types of blood clots.

Depending on the location of the blood clots, the type and extent of damage can become severe if not addressed promptly.

Concussions

Concussions are TBIs that may cause sudden loss of awareness or alertness for a moment, ranging from minutes to hours. Concussions cause changes to brain functioning and can be caused by trauma to the head or body.  Concussions are considered mild traumatic brain injuries.

Diffuse Axonal Injury

A diffuse axonal injury (DAI), a very common TBI, is a severe injury that causes extensive damage to the brain and the communication system between brain cells. Common events that cause the back-and-forth shaking of the brain can be falls, car accidents, or shaken baby syndrome. This injury can alter brain chemicals and cause further damage. DAI can be temporary or permanent, which can affect the recovery period. This TBI is usually associated with a coma.

Risk Factors for Brain Injuries

Brain injury risk factors include age, activity type, and even gender.

• Children and older adults are more prone to falls due to modifications to their coordination or motor skills.
• Individuals who are involved in high-speed and contact (both close and distant) activities are at risk of traumatic brain injuries.
• Males of all age groups have a higher risk that could be attributed to partaking in riskier activities.

Altered muscle coordination, mobility skills, and judgment can also increase the risk of experiencing a brain injury. Individuals in at-risk groups should take extra precautions to prevent and protect against head injuries.

What Events Can Cause a Brain Injury?

Some common events that cause head injury in humans fall into categories such as vehicle-associated accidents, bodily collisions (accidental or intentional), sports-related injuries, combat-related injuries, and direct physical violence.

• Vehicle-associated accidents are caused by collisions involving automobiles, motorcycles, or other types of transport vehicles. A pedestrian struck by a vehicle falls under this category.
• Bodily collisions (accidental or intentional) such as falling, tripping, or being pushed could result in head injury.
• Sports-related injuries are caused by physical trauma to the head and can be observed in a variety of sports including soccer, boxing, football, baseball, hockey, and other high-impact sports.
• Combat-related injuries are caused by explosives, direct blows to the head with debris or shrapnel, or even bodily collisions.
• Direct physical violence causes brain injury due to direct violent blows to the head from physical abuse (child or domestic), fighting, gunshot wounds to the head, or shaken baby syndrome.

Some immediate warning signs of moderate or severe brain injury caused by any of the above events are:

• Enlarged pupils
• Slurred speech
• Persistent and unrelenting headaches
• Seizures or convulsions
• Nausea or vomiting
• An inability to wake up
• Loss of coordination
• Weakness or numbness in extremities
• Agitation, confusion, or restlessness

The duration and strength of these warning signs vary depending on the severity of the injury.

Symptoms of a Brain Injury

There are a range of physical and psychological effects resulting from brain injury. Some symptoms are immediate, while others can be delayed for days or even weeks. A person experiencing a head injury might exhibit some or all the following symptoms in these three categories with different magnitudes (i.e., mild, moderate, or severe):

Potential physical symptoms of brain injury include:

• Headache
• Nausea or vomiting
• Lethargy or fatigue
• Slurred speech
• Dizziness, light-headedness, or loss of balance
• Bruise, bump, open wound, or object penetrating head
• Changes in skin coloration

Potential sensory symptoms include:

• Blurred vision
• Ear ringing (tinnitus)
• Sensitivity in taste
• Changes in the ability to smell
• Sensitivity to light or sound

Potential cognitive, behavioral, or mental symptoms of a brain injury include:

• Loss of consciousness (for seconds to a few minutes)
• Being dazed, confused, or disoriented
• Memory or concentration problems
• Alterations to mood
• Feeling depressed or anxious
• Changes in sleep pattern and length
• Difficulty with balance
• Coma

The strength and duration of symptoms experienced after a brain injury depend on many factors.

How Are Brain Injuries Diagnosed?

Several diagnostic testing tools are used to determine whether brain injury occurred and to what extent. They are often used in conjunction with a comprehensive medical evaluation, which allows medical personnel to obtain complete personal and family medical history and gain a better understanding of the event.

Diagnostic tests may include:

• Blood tests measure the amount of a specific protein in the blood after a traumatic brain injury event.
• A computed tomography (CT) scan is a diagnostic imaging procedure that combines X-rays and computer technology to produce horizontal, or axial, images of the body. It shows detailed images of any part of the body, including the bones, muscles, fat, and organs, and is usually more detailed than an X-ray.
• Electroencephalogram (EEG) is a technique that reports the brain’s continuous electrical activity using electrodes attached to the scalp.
• Magnetic resonance imaging (MRI) is a diagnostic procedure that combines large magnets, radio frequencies, and a computer to produce detailed images of organs and structures within the body.
• X-rays are diagnostic tests that employ invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs on film. They are particularly useful for cases of
  penetrating head trauma and gunshot wounds.

A brain injury can result in further neurological problems and may require future medical arrangements.

How Are Brain Injuries Treated?

Numerous factors will guide the treatment approach for a head injury by a clinician:

• Your age, overall health, and (personal and family) medical history
• Type of head injury
• Extent of the head injury
• Location of the head injury
• Your response to specific medications, procedures, or therapies
• Your view or predisposition

Depending on the severity of the injury, immediate care treatment options may include:

• Ice or cold press
• Rest
• Topical antibiotic ointment and adhesive bandage
• Observation by caregiver
• Immediate medical attention
• Stitches to protect the impacted area
• Hospitalization for observation by clinician
• Medication

Depending on the severity of the injury, long-term care treatment options may include:

• Hospitalization for treatment
• Sedation to promote healing
• Breathing assistance (with a breathing machine, mechanical ventilator, or respirator)
• Medication
• Surgery

Treatment options for brain injury are personalized to an individual as there are many variables to consider, such as the initiating head injury event, a person’s response to treatment, the status of other injuries sustained, and other existing comorbidities. It might be necessary to monitor for other events, such as brain swelling, increased intracranial pressure, or fluid volume changes, which can lead to additional brain damage.

How to Prevent Head Injury

You can take steps to promote a safe environment for children and adults to prevent head injury events:

• Use available protective equipment present in vehicles, such as seat belts and airbags, and secure cargo safely when traveling in vehicles, aircraft, locomotives, or watercraft. Children should always be secured in the appropriate safety or booster seat based on their weight class and size.
• Do not operate transportation vessels (i.e., motor vehicles, aircraft, locomotives, or watercraft) while under the influence of alcohol or drugs (including prescription medication), which can impair one’s ability.
• Wear protective equipment for the head while partaking in physical activities such as bicycle riding, in-line skating, skateboarding, riding a motorcycle, or operating a snowmobile or all-terrain vehicle (ATV). Wearing the appropriate head protection gear while playing sports, skiing, horseback riding, etc., will help prevent or minimize brain injury.

Consider the following to prevent head injuries in children:

• Install safety gates (on stairs or rooms with dangers) for children.
• Secure large furniture to help children avoid head injuries.
• Install window guards to prevent accidents.
• Place a nonslip mat in the shower or bathtub.
• Remove or secure area rugs.
• Discourage play in dangerous areas such as stairs, balconies, fire escapes, chimneys/fireplaces, or other places.

Consider the following to protect elders and prevent falls:

• Install handrails in bathrooms and on staircases.
• Place a nonslip mat in the shower or bathtub.
• Remove or secure area rugs.
• Install appropriate lighting to aid in increased visibility.
• Remove clutter from stairs and walkways.
• Maintain regular vision checkups.

What Complications Can Arise Due to Brain Injury?

Sometimes, complications can arise from any step in the process of a brain injury, starting at the initiating event step, through diagnosis, understanding symptoms, treatment, and eventual outcome. For a brain injury, the severity of the injury correlates to the severity of complications.

Moderate to severe brain injury can develop into prolonged or permanent changes in one’s state of consciousness (the state of being awake and aware of one’s surroundings) or responsiveness.

Effects on Consciousness

Coma is the state of loss of consciousness when you are unaware of anything and unable to respond to any stimulus to awaken. Comas vary in their level of severity and can be caused by various conditions. Some comas are reversible and treatable and resolve over time.

A vegetative state occurs when a person is awake but unaware of their surroundings. Their movements and actions are unintentional, and they are not aware of them. A vegetative state will be termed a “persistent vegetative state” if it lasts at least three months when not trauma-related and at least twelve months when trauma-related.

A minimally conscious state is a condition of altered consciousness where the person shows noticeable but limited signs of awareness and responds to stimulation.

Brain death, also referred to as brain stem death, occurs when a person who is on an artificial life support machine no longer has any brain functions and is not likely to regain consciousness or the ability to breathe without external support. Brain death is used as an indicator of legal death.

Effects on Physical Health

Brain injury can cause headaches which can begin within a week after the injury and can continue for several months. It can also cause damage to the blood vessel network, which can lead to a stroke, blood clots, or other problems dependent on the location.

Hydrocephalus (fluid buildup in the brain) can develop when cerebrospinal fluid accumulates in the spaces in the brain of some people who have had TBIs, resulting in increased pressure and swelling in the brain.

Some people develop seizures (or bursts of uncontrolled electrical activity between brain cells that cause momentary abnormalities in muscle tone or movements, behaviors, sensations, or states of awareness).

Infections can arise in areas affected by skull fractures or penetrating wounds that cause tears in the layers of protective tissues surrounding the brain. This can allow bacteria to enter the brain and cause infections resulting in meningitis that can spread to the rest of the nervous system if left untreated.

Brain injury can lead to the development of vertigo, feeling as if the environment around you is spinning in circles, causing dizziness. Individuals with brain injury may have an increased likelihood of developing degenerative diseases like Parkinson’s and Alzheimer’s disease.

Long-Lasting Symptoms

Brain injury can cause long-lasting symptoms that affect the senses, language, communication, emotions, or behaviors. Some people experienced the following effects:

• Senses: Tinnitus, balance impairments, difficulties in object recognition, vision issues, and alterations to taste buds.
• Language: An inability to organize thoughts and ideas or speech impairments; problems with writing and understanding speech, or impairments in following and participating in conversations.
• Communication: Difficulty understanding nonverbal cues or problems with changes in tone, pitch, or subtle differences in meaning. Some people might experience trouble with reading cues from listeners or with starting or stopping conversations. Others encounter an inability to use the muscles needed to form words (dysarthria).
• Emotions: Insomnia, mood alterations, anxiety, depression, irritability, lack of empathy, and anger.
• Behavior: Verbal or physical outbursts, lack of awareness of abilities, challenges with self-control, and even difficulty managing in social situations.

Combatting complications might require long-term medical and rehabilitative therapy. The scope of one’s recovery depends on several factors, including the type of brain injury, concurrent injuries, and other comorbidities. It is important to ensure a support system is in place for the transition back to home or to the community. Promoting a positive mindset will help encourage independence and build confidence.

The Bottom Line About Brain Injuries

Brain injuries can have a profound effect on one’s life. They are scary to experience, and the uncertainty of the outcome can be heavy. However, they are preventable if the appropriate measures are taken. If they do occur, there are effective treatment options to have successful outcomes, and if complications arise, they can be overcome with resources and a strong support system.