Introduction to Traumatic Brain InjuryJoe Rosenthal, MD

Clinical Assistant ProfessorTBI Fellow

11/1/10

Objectives

• Definition• Epidemiology• Severity of injury• Mechanisms/Types of Brain Injury• Symptoms/Treatment• Return to work and driving

Definition

• Nondegenerative, noncongenital insult to the brain from an external mechanical force, possibly leading to permanent or temporary impairments of cognitive, physical, and psychosocial functions with an associated diminished or altered state of consciousness

www.cdc.gov/features/dsTBI_BrainInjury/

National Center for Injury Prevention and Control at the Center for Disease Control

Survival in the USA

• Mild (80% of all TBI’s)– 100% (nearly) survive

• Moderate (10% of all TBI’s)– 93% survive

• Severe (10% of all TBI’s)– 42% survive

Risk Factors

• Young (15-24 year olds – Highest Risk)• Low income• Unmarried• Minority • Inner city• Male (2x more likely)• Substance abuse• Previous TBI

Common Causes in the United States

• #1 MVA– 50%– 2.4:1 Male

• #2 Falls– 20-30% (most common > 75 yo)

• #3 Firearms– 12% (age 25-34)– 6:1 Male

What is the Most Common INDIRECT Cause of TBI?

Most Common INDIRECT Cause

ALCOHOL

TBI Spectrum

Mild/Concussion Moderate Severe Death

Determining Severity

• Loss of Consciousness Duration

• Post Traumatic Amnesia & Confusion

• Wounds, Bruising, Swelling

• Tools:– Glascow Coma Scale (GCS)– Radiographic Imaging

Mild TBI

• Traumatically induced physiologic disruption of brain function, as manifested by one of the following:– LOC up to 30 minutes– Anterograde or retrograde amnesia not greater

than 24 hours– Altered mental status– Focal neurologic deficits

• Headaches, nausea, wooziness, etc.

Other Mild TBI Criteria

• GCS 13-15

• No Head CT abnormalities

• Hospital stay < 48 hrs

• No operative lesions

Complicated Mild TBI

• Mild TBI with small amount of bleed, bruising, swelling, or skull fracture seen on imaging

• Higher risk of more chronic symptoms

Moderate TBI

• GCS 9-12

• PTA>24hrs

• Coma duration 20 minutes to 6 hours

• Abnormalities on CT

• Operative intracranial lesion

• Hospital stay at least 48 hrs

Severe TBI

• GCS 3-8

• Coma duration 6+ hours

Why is the Brain so Vulnerable?

Brain Injury Types

• Contusion

• DAI

• Penetrating Injuries

• Intracranial Hemorrhage

• Secondary Injuries (including Hypoxia)

Contusion

• Low velocity impact

• Often symmetric (coup-countercoup)

• Not responsible for coma

• Focal deficits

• Recovery dependent on size and location

• Occasionally require resection

Injury Not Always Just atImpact Site

Diffuse Axonal Impact

• High velocity impact• Almost always has some time of

unconsciousness• Diffuse pattern of deficits• Recovery gradual

Diffuse Axonal Injury

• Widespread stretching of axons – Rotation on axis– Acceleration-deceleration

• Mild force - external

• Severe force - internal

• Often imaging is normal

http://braininjury.blogs.com/photos/uncategorized/closedheadinjury.jpg

Penetrating Injuries

• Missile (Gun shot wound)

• Non-missile (ice pick)

• Only primary mechanism on the rise

Penetrating Injuries

• GSW– Damage along track of bullet and embedded bone

fragments– Usually lead to focal deficits

• Energy = ½ mass x velocity squared– High velocity missiles cause most damage

Intracranial Hemorrhage

• Epidural Hematoma– Impact loading with laceration of dural arteries– Often with fracture of temporal bone and tear

of middle meningeal artery.– RAPID neurologic deterioration

Intracranial Hemorrhage

• Subdural Hematoma– Injury to cortical bridging veins most common– Slow collection of blood– “Lucid interval”

• Actress Natasha Richardson

– High mortality rate– Often need evacuation

Intracranial Hemorrhage

• Intraparenchymal hemorrhage– Cerebral parenchyma– Injury to deeper, larger cerebral vessels– Different mechanism and often more diffuse

deficits compared to CVA bleed

Intraventricular Hemorrhage

– Occur with very severe TBI– Unfavorable prognosis due to severity of

injury

Anoxic/Hypoxic Brain Injury

• Caused by lack of oxygen to brain

• Most common cause: Cardiac Arrest

• Other causes: near drowning, infection, respiratory arrest, choking, Carbon Monoxide poisoning, etc.

Wijdicks EFM, Campeau NG, Miller GM (2001)

Secondary Injuries

• Systemic– Hypoxia/Anoxia– Hypotension– Anemia– Hyperthermia– Hyper/hypocarbia– Fluid imbalance– Sepsis

• CNS– Brain swelling (Inc ICP)– Hemorrhage/Hematoma– Brain herniation– Seizures– Hydrocephalus– Ischemia– Infection

Journey to Recovery

Immediate Treatment

• Observation – alertness, confusion, Headache, nausea, etc.

• Blood Pressure & other vitals monitoring

• Imaging

• Surgery

• Intracranial Pressure Monitoring

Traumatic Brain Injury Sequela• Agitation• Mood Disorder• Sleep Disturbance• Motor Dysfunction• Cognitive Deficits• Headaches• Decreased Arousal• Bowel & Bladder Dysfunction• Pain Syndromes• Seizures• Denial of Disability

Amnesia

http://braininjuryrx.com/2009/06/misconceptions-made-by-nursing-students-about-amnesia-in-tbi/

Posttraumatic AmnesiaDefinitions

• period of impaired consciousness after brain injury

• “ending” at the time the patient can give a clear, consecutive account of what is happening around them

• absence of continuous memory or inability to retain new information

• broader syndrome of disorientation, confusion, diminished memory, reduced capabilities to attend to and respond to environmental issues

Post- Traumatic Headaches

• Very common, especially after Mild-Mod TBI• Different Types:

– Migraine– Tension– Related to Neck injury/pain

• Treatment– Time– Medications

Sleep Disorders

• Trouble Falling Asleep– Common after TBI– Often treated with good sleep hygiene and/or meds

• Trouble Staying Awake– Decreased arousal during the day– Tx: good sleep hygiene, medications

• Nightmares– Associated with PTSD

Cognitive Changes

http://www.braybray.co.uk/cms/photo/misc/head_injuries.gif

Other Cognitive Deficits

• Short Term and Working Memory Problems

• Decreased Attention

• Cognitive Fatigue

• Problem Solving difficulties

Emotional/Personality Changes

• Depression• Anxiety• Irritability• Anger/Aggression• Obsessive/Compulsive

• Often pre-injury psychiatric conditions are exacerbated after injury

Incidence of Anxiety and Depression after

Traumatic Brain injury

• Depression 61%

• Anxiety 17%

• Anxiety and depression 60%

Frequent Complaints with TBI related Depression

• Frustration 81%

• Restlessness 73%

• Boredom 66%

• Sadness 66%

Treatment

• For the most part, same as non-injured pts– Counseling– Anti-depressants– Other medications– Monitor for other conditions that can cause

Depression (i.e. low thyroid)

Movement Disorders

• Weakness

• Spasticity

• Abnormal movements

• Difficulty coordinating movements

Visual Deficits

• Blurry Vision

• Double Vision

• Trouble opening and closing eyelids

• Blindness

Dizziness & Vertigo

• Inner ear damage -- ringing in ears• Lightheadedness from blood pressure

problems• Injury directly to brain resulting in these

symptoms

• Tx

Other Senses

• Taste change

• Loss of smell

• Numbness/tingling

Post Concussive Syndrome

Persistent, chronic symptoms after the expected time of recovery-Headache, dizziness, fatigue, irritability, sleep disturbance, mood changes, etc.

Controversial-Definition-Timing (1 month vs 3 months)-# of symptoms

RehabilitationMulti-Disciplinary Approach

• Physicians– Medication– Monitoring labs– Managing therapies– Clearance for return to

work/drive

• Nursing (in-patient)– Bowel and bladder– Wound Care– Family education

• Therapists– PT/OT/ST/Rec

Therapy– Community re-entry,

assist with return to work/driving

• Neuropsychologist– Testing– Counseling

• FAMILY/FRIENDS

Return To Work

• Dependent on multiple factors– Severity of injury– Cognitive functioning– Type of job– Symptoms– Physical limitations

Return to Work

• Tools to assess readiness– Physician visits– Therapy reports– Neuropsychological testing

Epidemiology of Traumatic Brain Injuryin the United States

Return to Work

• mild 90-100%

• moderate poor data

• severe 10-25%

Return to WorkPossible Accommodations

• New position (less demanding, safer)

• Frequent rest breaks

• Return Part Time

• Work Conditioning/Hardening with therapy

• Vocational Training (BVR)

• Memory Aids

Return to Driving

• Again, dependent on multiple factors– Severity of injury– Cognitive functioning– Symptoms– Physical limitations– Seizures

• Tools to assess readiness– Therapy results– Vision evaluation– Driver’s Evaluation

Questions

References• Brain injury medicine. Principles and Practice. 2007.• Physical medicine and rehabilitation: Principles and practice. Fourth

edition.2005.• Physical medicine and rehabilitation board review. 2004.• Pharmacologic enhancement of cognitive and behavioral deficits after

traumatic brain injury. Olli Tenovuo. Current Opinion in Neurology 2006, 19:528-533.

• High-Yield Neuroanatomy. Second Edition. 2000• Traumatic brain injury diagnosis and outcome. W. Jerry Mysiw, M.D.• eMedicine – Traumatic brain injury: Definition, epidemiology,

pathophysiology. http://www.emedicine.com/pmr/topic212.htm• Sleep disturbances following Traumatic Brain Injury. Rao V & Rollings P.

Current Treatment Options in Neurology. 2002, 4:77-87.