Traumatic Brain Injury: Types, Symptoms, and Treatment

23 September,2024

The cranium or skull protects the brain and surrounding structures, including blood vessels, tissues, and the scalp. However, all these structures are susceptible to injury. Such injuries are collectively grouped under head injuries or acquired brain injuries. Acquired brain injuries can be of two types - traumatic or non-traumatic.

A traumatic brain injury happens due to external force to the head that causes some damage to the brain. They are one of the most prevalent causes of death or disability worldwide. As per the World Health Organization (WHO), around 69 million people encounter some form of traumatic brain injury annually. As a result, traumatic brain injuries are considered to be a “silent epidemic.” 

Any traumatic brain injury can prove to be life-threatening and requires immediate medical attention. The effects of these injuries can last for a short period or lifelong. Most traumatic brain injuries are treatable, but it is possible to prevent them from occurring in the first place.

This blog explains traumatic brain injury, its types, signs and symptoms, treatment options, and prevention in detail.

What is a Traumatic Brain Injury (TBI)?

A head injury that damages the brain, often as a result of an external physical force, is termed a traumatic brain injury (TBI). The damage can be caused by a sudden bump or jolt to the head or a foreign object penetrating the skull. In the case of skull fractures, the skull fragments themselves may penetrate the brain and cause injury. Based on the severity of the injury, it can cause temporary loss of function, permanent disability, coma, or even death.

How are Traumatic Brain Injuries Classified?

Traumatic brain injuries are of several types depending on the cause, severity, features, and other factors. Most traumatic brain injuries are classified into two broad groups -

• Penetrating TBI: A penetrating brain injury occurs when a foreign object pierces the skull and reaches the brain tissue. It is also known as an open TBI. Objects such as a bullet, knife, shrapnel, or bone tissue can penetrate the skull and damage a part of the brain.
• Non-penetrating TBI: In a non-penetrating TBI, the brain is injured, but the skull is intact. When the head suddenly jerks, the brain moves rapidly within the skull, bruising tissue and tearing blood vessels. It is also known as a blunt TBI or closed TBI. Non-penetrating TBIs occur in road traffic accidents, falls, and certain sports. Vigorously shaking a baby can also cause non-penetrating TBIs, known as shaken baby syndrome.

The Glasgow Coma Scale (GCS) helps determine the severity of a traumatic brain injury by scoring the patient’s reactions to stimuli on a scale of 3 to 15. Post-traumatic amnesia (PTA) duration and loss of consciousness (LOC) are also helpful in judging the severity. Depending on the severity, traumatic brain injuries are classified as -

• Mild TBI: When the patient has a GCS score of 13 or more, post-traumatic amnesia duration is less than a day, and loss of consciousness lasts from 0 to 30 minutes, the injury is adjudged as mild. Mild traumatic brain injuries are pretty common, and they can have adverse, long-lasting effects.
• Moderate TBI: A moderate TBI is when the patient has a Glasgow Coma Scale score between 9 and 12, post-traumatic amnesia duration of one to seven days, and loss of consciousness between 30 minutes and 24 hours.
• Severe TBI: For a severe TBI, the Glasgow Coma Scale score is below 8, the post-traumatic amnesia duration is more than seven days, and loss of consciousness lasts for over 24 hours.

How is Traumatic Brain Injury Differentiated Based on the Area of the Injury?

Based on the area of the injury, traumatic brain injuries are of two types - 

• Focal TBIs: When the injury affects a specific area of the brain, it is referred to as a focal traumatic brain injury. A focal injury usually occurs when there is a sudden blow to the head or due to a penetrating brain injury. Symptoms of a TBI correspond with the injury-affected area. These injuries are easily diagnosed using routine diagnostic methods.
• Diffuse TBIs: When an injury covers multiple areas of the brain, it is known as a diffuse or multifocal traumatic brain injury. Diffuse TBIs often occur due to acceleration/deceleration injuries or rotational forces. The damage caused by these injuries is difficult to detect by regular diagnostic methods.

In several cases, focal and diffuse TBIs may be present at the same time as a result of the same traumatic event.

What are Primary and Secondary Brain Injuries?

Post a traumatic brain injury, the time taken for brain damage to occur leads to two types of injuries -

• Primary: Primary brain injuries are physical injuries that occur during impact. These injuries damage brain structures such as blood vessels, axons, neurons, the blood-brain barrier, and meninges. Primary injuries often occur due to road traffic accidents, falls, and gunshots.
• Secondary: Secondary injuries refer to the delayed effects of a primary brain injury. They are changes in the brain that take place over a prolonged duration of several hours or days. In around 40% of traumatic brain injury cases, brain damage occurs due to secondary injuries, thus further deteriorating the patient’s condition.

Other Types of Traumatic Brain Injuries 

Apart from primary, secondary, mild, moderate, and severe traumatic brain injuries, there are several other types too. These are - 

• Coup-contrecoup injury: When the head hits a stable surface or object, the injury that occurs right below the impact site is known as a coup injury. The injury occurring on the exact opposite side is a contrecoup injury. These injuries may be present independently or at the same time. When they occur during the same event, it is known as a coup-contrecoup injury. A coup injury is more likely if the head is stationary and the object is moving. Conversely, a contrecoup injury is more common if the head is moving and the object is stationary.
• Concussion: A concussion is a type of mild TBI that damages the brain temporarily and causes short-term changes in brain function. It occurs when there is a sudden jolt or blow to the head. A person with a concussion displays symptoms including headaches, temporary loss of consciousness, memory loss, blurred vision, nausea, vomiting, dizziness, and problems with balance, thinking, and concentration. These symptoms may appear at the time of injury or within a few days.
• Contusion: A brain contusion or cerebral contusion is the bruising of brain tissue caused by a sudden blow to the head. This injury occurs when the brain moves back and forth within the skull. A contusion causes bleeding and swelling of the brain. Symptoms of a contusion depend on the area of the brain injured.
• Skull fractures: The skull consists of eight bones. When any one or more of them incurs damage, it is known as a skull fracture. Skull fractures result from blunt force trauma to the head. Types of skull fractures include linear fractures, depressed fractures, diastatic fractures, and basilar fractures.
• Diffuse axonal injury (DAI): A DAI causes the tearing of the brain’s long connecting nerve fibers, or axons. It affects a widespread area of the brain, mainly the white matter tracts. It is a form of severe traumatic brain injury and is most often seen in motor vehicle accidents. A DAI is one of the most common types of brain injury and can lead to coma, permanent vegetative state, or even death.

What Causes a Traumatic Brain Injury?

Traumatic brain injuries have several causative factors, including - 

• Falling: The leading cause of a traumatic brain injury is falls. Falling from a height, in the bathroom, and other types of falls lead to a TBI. Older adults and children sustain TBIs due to falling most often.
• Accidents: TBIs caused by road traffic accidents, motor vehicle crashes, car accidents, bicycle accidents, and pedestrian accidents are common. TBIs can also happen due to workplace accidents in certain occupations.
• Violence and Assault: TBIs can occur as a result of violent attacks in cases of domestic violence, child abuse, or gunshots. Children often sustain TBIs when shaken violently, known as shaken baby syndrome.
• Sports and Recreational Activities: Sportspersons who play contact sports such as boxing, martial arts, or rugby and other sports such as football, hockey, skiing, or skateboarding are prone to TBIs. Extreme recreational activities also significantly contribute to traumatic brain injuries.
• Military Activities: Military personnel in war zones sustain TBIs due to blast injuries from firearms and explosives. Traumatic brain injuries are the most common reason for death and disability among the armed forces.

What Signs and Symptoms Indicate a Traumatic Brain Injury?

Symptoms of traumatic brain injury vary according to the severity of the injury. However, mild, moderate, and severe TBIs cause physical, cognitive, behavioral, and sensory alterations that manifest as symptoms of the injury.

Symptoms of Mild TBI

• The most common physical symptoms of a mild TBI include headache, nausea, vomiting, drowsiness, and fatigue.
• A person with a mild TBI may also experience dizziness, balance issues, and vision problems such as blurred or double vision. They also exhibit increased sensitivity to light and sound.
• Several sensory symptoms are also present, such as a ringing sound in the ears (tinnitus), changes in smelling ability, and an unsavory taste in the mouth.
• Patients experience cognitive and behavioral symptoms such as short-term loss of consciousness, problems with memory and concentration, anxiety, depression, irritability, mood swings, disorientation, and sleep issues.

Symptoms of Moderate and Severe TBI

• In moderate or severe traumatic brain injuries, several advanced symptoms are present, along with the symptoms of a mild TBI.
• Physical symptoms of moderate and severe TBIs include long-term loss of consciousness that lasts for several minutes or hours, worsening or persistent headaches, unequal pupil sizes (anisocoria), seizures, clear fluids leaking from ears or nose, and weakness in arms and legs.
• Cognitive and behavioral changes seen in moderate and severe TBIs include issues with communication and memory, inability to think clearly, increased confusion, slurred speech, inability or difficulty to wake up from sleep, aggressiveness, agitation, impulsive behavior, and coma.

Symptoms of Traumatic Brain Injury in Children

When children experience a traumatic brain injury, they might not be able to express the symptoms they are dealing with. To determine a TBI in children, adults can look for symptoms such as - 

• Altered eating or nursing habits
• Inconsolable crying
• Irritability
• Crankiness
• Lack of interest in favorite activities
• Loss of skills
• Seizures
• Changes in sleeping pattern
• Alteration in mood, such as sadness or depression
• Altered ability to pay attention

How are Traumatic Brain Injuries Diagnosed?

If a traumatic head injury is suspected, the doctor will advise some diagnostic tests to confirm the injury and judge its extent. They will also attempt to determine the injury’s circumstances and causative factors. Tests used to detect a traumatic brain injury include - 

• Medical examination, where the doctor will obtain specific information about the injury and related details.
• Neurologic examination to judge the patient’s mental status, reflexes, motor function, sensory perception, coordination, balance, and other vital functions.
• Imaging tests, including CT scans and MRIs, to check for bleeding, swelling, and other changes in the brain.
• Glasgow Coma Scale score to determine the severity of the injury.
• Other tests include blood tests, angiography, electroencephalography, and neurocognitive tests.

How is a Traumatic Brain Injury Treated?

The severity of a traumatic brain injury dictates its treatment. The doctor will administer the appropriate treatment once the injury is diagnosed and classified correctly.

Treatment of Mild TBI

• Usually, a mild traumatic brain injury does not require any treatment.
• The doctor might prescribe over-the-counter pain-relieving medication to manage headaches.
• The patient should rest for a few days, but completely stopping mental and physical activities is not recommended.
• The doctor will monitor the patient’s condition to check for new symptoms or the worsening of existing ones. If this happens, the patient should seek immediate medical help.

Treatment of Moderate and Severe TBI

Moderate or severe traumatic brain injuries are deemed medical emergencies. In this case, the doctor will ensure that the patient receives oxygen and blood supply and stabilize the patient to prevent further injuries.

In most cases, patients will require emergency surgery for various purposes. A surgeon will perform surgery to -

• Relieve pressure inside the skull (intracranial pressure)
• Repair skull fractures
• Remove hematomas (blood clots in the brain)
• Remove foreign objects that have entered the skull
• Remove damaged or dead brain tissue

Medications for Treatment of TBI

The doctor will prescribe certain medications for symptomatic relief from a traumatic brain injury and to minimize secondary damage to the brain. Some medicines used in the treatment of TBIs are - 

• Pain medications
• Anticonvulsant medicines to control brain damage due to seizures
• Coma-inducing medicines to put the patient in a coma temporarily to reduce the oxygen requirement of the brain
• Diuretics to reduce pressure in the brain
• Anticoagulants to stop the formation of blood clots
• Stimulants to keep the patient alert and attentive
• Antianxiety and antidepressants to stabilize the patient’s mood and reduce fear and nervousness

How Do Traumatic Brain Injuries Cause Complications?

A traumatic brain injury can lead to several complications, both short-term and long-term. These complications depend on the severity of the injury.

Complications of Mild TBI

• The complications that occur after a concussion are termed post-concussion syndrome. A person with this condition experiences symptoms such as headaches, dizziness, increased sensitivity to noise, memory and concentration problems, anxiety, depression, irritability, and mood swings.
• There is an increased risk of second impact syndrome after a mild TBI, where the brain swells rapidly if a second injury happens before the first injury heals completely.

Complications of Moderate and Severe TBI

More severe forms of traumatic brain injuries have adverse effects on consciousness, physical complications, cognitive abilities, sensory functions, and emotional well-being.

The patient may experience varying levels of consciousness after a traumatic brain injury, such as -

• Stupor
• Coma
• Persistent vegetative state
• Minimally conscious state
• Locked-in syndrome
• Brain death

TBIs cause impairment of cognitive abilities and communication problems, including-

• Problems with memory
• Learning disabilities
• Attention and concentration problems
• Difficulty with speech or writing
• Impaired social skills

Sensory complications of TBIs include - 

• Impaired hand-eye coordination
• Ringing sound in the ears (tinnitus)
• Tingling or itching sensation on the skin
• Foul taste
• Impaired sense of smell
• Vision problems

Physical complications of TBIs include infections, seizures, hydrocephalus, hematomas, and vertigo.

Emotional and behavioral changes as a result of TBIs are depression, anxiety, mood swings, irritability, apathy, impulsiveness, insomnia, and drug or alcohol abuse.

TBIs also increase a person’s risk of degenerative brain diseases, such as Alzheimer’s disease, Parkinson’s syndrome, and dementia pugilistica.

What is the Recovery Process for a Traumatic Brain Injury?

Patients with extensive traumatic brain injuries require rehabilitation to resume regular activities after the completion of treatment. Rehabilitation may include - 

• Physical therapy
• Speech therapy
• Occupational therapy
• Respiratory therapy
• Psychological therapy
• Cognitive therapy
• Vocational counseling

The prognosis of a mild to severe traumatic brain injury depends on multiple factors, such as the type of the injury, the area of the brain affected, access to emergency treatment, the patient’s age and overall health, and existing comorbidities.

How to Prevent a Traumatic Brain Injury?

In most cases, traumatic brain injuries are entirely preventable by taking some precautionary measures, such as -

• Wearing seatbelts while driving a car
• Wearing helmets while riding bikes or bicycles
• Avoiding driving motor vehicles under the influence of drugs or alcohol
• Not using a phone while driving or walking on roads
• Wearing appropriate protective gear and helmets while playing sports

The risk of falling, especially for older adults, can be minimized by - 

• Installing handrails in bathrooms and staircases
• Removing rugs or mats that might pose tripping hazards
• Improving lighting around the house
• Getting regular eye tests

TBIs in children are also preventable by taking steps such as -

• Placing non-slip mats in the shower
• Installing safety gates on staircases
• Installing shock-absorbing materials in playgrounds
• Continuously supervising children to prevent falls

Takeaway

A traumatic brain injury happens when there is a blow to the head, leading to brain damage. They are one of the most common causes of death and disability. Although traumatic brain injuries can have catastrophic consequences and lead to complications such as coma or death, they are almost always preventable by adopting some safety measures. TBIs of all severities must be treated as medical emergencies. If someone is experiencing signs of a traumatic brain injury, they must seek medical help immediately to prevent further complications.