BRAIN INJURIES DEFINITION
Traumatic brain injury (TBI) is a nondegenerative, noncongenital insult to the brain from an external mechanical force, possibly leading to permanent or temporary impairment of cognitive, physical, and psychosocial functions, with an associated diminished or altered state of consciousness.
The definition of TBI has not been consistent and tends to vary according to specialties and circumstances. Often, the term brain injury is used synonymously with head injury, which may not be associated with neurologic deficits. The definition also has been problematic with variations in inclusion criteria.
BRAIN INJURIES CAUSES
In general, head injuries can be divided into two categories based on what causes them. They can either be head injuries due to blows to the head or head injuries due to shaking.
Head injuries caused by shaking are most common in infants and small children, but they can occur any time you experience violent shaking.
Head injuries caused by a blow to the head are usually associated with:
- motor vehicle accidents
- physical assaults
- sports-related accidents
In most cases, your skull will protect your brain from serious harm.
BRAIN INJURIES PATHOPHYSIOLOGY
Glasgow Coma Scale
The Glasgow Coma Scale (GCS) defines the severity of a TBI within 48 hours of injury.
See the list below:
- Spontaneous = 4
- To speech = 3
- To painful stimulation = 2
- No response = 1
See the list below:
- Follows commands = 6
- Makes localizing movements to pain = 5
- Makes withdrawal movements to pain = 4
- Flexor (decorticate) posturing to pain = 3
- Extensor (decerebrate) posturing to pain = 2
- No response = 1
See the list below:
- Oriented to person, place, and date = 5
- Converses but is disoriented = 4
- Says inappropriate words = 3
- Says incomprehensible sounds = 2
- No response = 1
The severity of TBI according to the GCS score (within 48 h) is as follows:
- Severe TBI = 3-8
- Moderate TBI = 9-12
- Mild TBI = 13-15
Ranchos Los Amigos Scale Of Cognitive Functioning
The severity of deficit in cognitive functioning can be defined by the Ranchos Los Amigos Scale.
- level I = No response
- level II = Generalized response
- level III = Localized response
- level IV = Confused-agitated
- level V = Confused-inappropriate
- level VI = Confused-appropriate
- level VII = Automatic-appropriate
- level VIII = Purposeful-appropriate
TBI DEFINED BY THE HEAD INJURY INTERDISCIPLINARY SPECIAL INTEREST GROUP OF THE AMERICAN CONGRESS OF REHABILITATION MEDICINE
The Head Injury Interdisciplinary Special Interest Group of the American Congress of Rehabilitation Medicine defines mild head injury as “a traumatically induced physiologic disruption of brain function, as manifested by one of the following:
- Any period of loss of consciousness (LOC),
- Any loss of memory for events immediately before or after the accident,
- Any alteration in mental state at the time of the accident,
- Focal neurologic deficits, which may or may not be transient.”
The other criteria for defining mild TBI include the following:
- GCS score greater than 12
- No abnormalities on computed tomography (CT) scan
- No operative lesions
- Length of hospital stay less than 48 hours
The following criteria define moderate TBI:
- Length of stay at least 48 hours
- GCS score of 9-12 or higher
- Operative intracranial lesion
- Abnormal CT scan findings
BRAIN INJURIES SYMPTOMS
Traumatic brain injury can have wide-ranging physical and psychological effects. Some signs or symptoms may appear immediately after the traumatic event, while others may appear days or weeks later.
Mild Traumatic Brain Injury
The signs and symptoms of mild traumatic brain injury may include:
- Loss of consciousness for a few seconds to a few minutes
- No loss of consciousness, but a state of being dazed, confused or disoriented
- Nausea or vomiting
- Fatigue or drowsiness
- Difficulty sleeping
- Sleeping more than usual
- Dizziness or loss of balance
- Sensory problems, such as blurred vision, ringing in the ears, a bad taste in the mouth or changes in the ability to smell
- Sensitivity to light or sound
Cognitive Or Mental Symptoms
- Memory or concentration problems
- Mood changes or mood swings
- Feeling depressed or anxious
Moderate To Severe Traumatic Brain Injuries
Moderate to severe traumatic brain injuries can include any of the signs and symptoms of mild injury, as well as the following symptoms that may appear within the first hours to days after a head injury:
- Loss of consciousness from several minutes to hours
- Persistent headache or headache that worsens
- Repeated vomiting or nausea
- Convulsions or seizures
- Dilation of one or both pupils of the eyes
- Clear fluids draining from the nose or ears
- Inability to awaken from sleep
- Weakness or numbness in fingers and toes
- Loss of coordination
Cognitive Or Mental Symptoms
- Profound confusion
- Agitation, combativeness or other unusual behavior
- Slurred speech
- Coma and other disorders of consciousness
Infants and young children with brain injuries may lack the communication skills to report headaches, sensory problems, confusion and similar symptoms. In a child with traumatic brain injury, you may observe:
- Change in eating or nursing habits
- Persistent crying and inability to be consoled
- Unusual or easy irritability
- Change in ability to pay attention
- Change in sleep habits
- Sad or depressed mood
- Loss of interest in favorite toys or activities
BRAIN INJURIES DIAGNOSIS
One of the first ways your doctor will assess your head injury is with the Glasgow Coma Scale (GCS). The GCS is a 15-point test that assesses your mental status. A high GCS score indicates a less severe injury.
Your doctor will need to know the circumstances of your injury. Often, if you have suffered a head injury, you won’t remember the details of the accident. If it’s possible, you should bring someone with you who witnessed the accident. It will be important for your doctor to determine if you lost consciousness and for how long if you did.
Your doctor will also examine you to look for signs of trauma, including bruising and swelling. You’re also likely to get a neurological examination, in which your doctor will evaluate your nerve function by assessing your muscle control and strength, eye movement, and sensation, among other things.
Imaging tests are commonly used to diagnose head injuries. A CT scan will help your doctor look for fractures, evidence of bleeding and clotting, brain swelling, and any other structural damage. CT scans are fast and accurate, so they’re typically the first type of imaging you will receive. You may also receive an MRI scan, which can offer a more detailed view of the brain. An MRI scan will usually only be ordered once you’re in stable condition.
BRAIN INJURIES TREATMENT
Mild traumatic brain injuries usually require no treatment other than rest and over-the-counter pain relievers to treat a headache. However, a person with a mild traumatic brain injury usually needs to be monitored closely at home for any persistent, worsening or new symptoms. He or she also may have follow-up doctor appointments.
The doctor will indicate when a return to work, school or recreational activities is appropriate. It’s best to avoid physical or thinking (cognitive) activities that make things worse until symptoms have resolved. Most people return to normal routines gradually.
Immediate Emergency Care
Emergency care for moderate to severe traumatic brain injuries focuses on making sure the person has an adequate oxygen and blood supply, maintaining blood pressure, and preventing any further injury to the head or neck.
People with severe injuries may also have other injuries that need to be addressed. Additional treatments in the emergency room or intensive care unit of a hospital will focus on minimizing secondary damage due to inflammation, bleeding or reduced oxygen supply to the brain.
Medications to limit secondary damage to the brain immediately after an injury may include:
- Diuretics. These drugs reduce the amount of fluid in tissues and increase urine output. Diuretics, given intravenously to people with traumatic brain injury, help reduce pressure inside the brain.
- Anti-seizure drugs. People who’ve had a moderate to severe traumatic brain injury are at risk of having seizures during the first week after their injury.
An anti-seizure drug may be given during the first week to avoid any additional brain damage that might be caused by a seizure. Additional anti-seizure treatments are used only if seizures occur.
- Coma-inducing drugs. Doctors sometimes use drugs to put people into temporary comas because a comatose brain needs less oxygen to function. This is especially helpful if blood vessels, compressed by increased pressure in the brain, are unable to deliver the usual amount of nutrients and oxygen to brain cells.
Emergency surgery may be needed to minimize additional damage to brain tissues. Surgery may be used to address the following problems:
- Removing clotted blood (hematomas). Bleeding outside or within the brain can result in a collection of clotted blood (hematoma) that puts pressure on the brain and damages brain tissue.
- Repairing skull fractures. Surgery may be needed to repair severe skull fractures or to remove pieces of skull in the brain.
- Opening a window in the skull. Surgery may be used to relieve pressure inside the skull by draining accumulated cerebral spinal fluid or creating a window in the skull that provides more room for swollen tissues.
Most people who have had a significant brain injury will require rehabilitation. They may need to relearn basic skills, such as walking or talking. The goal is to improve their abilities to perform daily activities.
Therapy usually begins in the hospital and continues at an inpatient rehabilitation unit, a residential treatment facility or through outpatient services. The type and duration of rehabilitation varies by individual, depending on the severity of the brain injury and what part of the brain was injured.
Rehabilitation specialists may include:
- Physiatrist, a doctor trained in physical medicine and rehabilitation, who oversees the entire rehabilitation process, manages medical rehabilitation problems and prescribes medication as needed
- Occupational therapist, who helps the person learn, relearn or improve skills to perform everyday activities
- Physical therapist, who helps with mobility and relearning movement patterns, balance and walking
- Speech and language pathologist, who helps the person improve communication skills and use assistive communication devices if necessary
- Neuropsychologist, who assesses cognitive impairment and performance, helps the person manage behaviors or learn coping strategies, and provides psychotherapy as needed for emotional and psychological well-being
- Social worker or case manager, who facilitates access to service agencies, assists with care decisions and planning, and facilitates communication among various professionals, care providers and family members
- Rehabilitation nurse, who provides ongoing rehabilitation care and services and who helps with discharge planning from the hospital or rehabilitation facility
- Traumatic brain injury nurse specialist, who helps coordinate care and educates the family about the injury and recovery process
- Recreational therapist, who assists with time management and leisure activities
- Vocational counselor, who assesses the ability to return to work and appropriate vocational opportunities and who provides resources for addressing common challenges in the workplace