Traumatic Brain Injury (TBI)

Traumatic Brain Injury (TBI)

Brain tissue contacting a firm surface causing an alteration in consciousness

Acquired Brain Injury

Term sometimes used interchangeably with TBI in literature

TBI Incidence US

Approximately 2.9 million TBI-related ED visits annually

Mild TBI Survival Rate

Nearly 100 percent survival

Moderate TBI Survival Rate

Approximately 93 percent survival

Severe TBI Survival Rate

Approximately 42 percent survival

Major Contributors to Improved Survival

Advances in medical technology and prevention of secondary injury

Common TBI Causes

MVAs falls assaults sports and recreational accidents

Substance Use and TBI

Highly associated with alcohol or drug use

High-Risk Age Groups for TBI

Infants young adults and older adults

Infant TBI Causes

Child abuse and falls

Young Adult TBI Causes

Motor vehicle accidents and risky behaviors

Older Adult TBI Causes

Falls

Sex Differences in TBI

Men affected more frequently than women

Typical TBI Demographic

Men aged 15 to 24 years

Primary Injury

Direct mechanical damage to brain tissue at time of impact

Secondary Injury

Delayed injury processes occurring hours to months after TBI

Secondary Injury Mechanisms

Excitotoxicity hypoxemia hypotension ischemia edema and elevated ICP

Excitotoxicity

Excess neurotransmitter release leading to neuronal cell death

Acceleration-Deceleration Injury

Rapid movement causing contusions lacerations and hematomas

Rotational Forces

Cause shearing of axons leading to DAI

Contusion

Bruising of brain tissue with surface vessel hemorrhage

Coup Lesion

Brain injury on the same side as the impact

Contrecoup Lesion

Brain injury on the opposite side of impact

Traumatic Axonal Injury (TAI)

Shearing and stretching of axons due to rotational forces

Diffuse Axonal Injury (DAI)

Widespread axonal injury associated with severe TBI and poor prognosis

DAI Imaging

Often not visible on CT and may require MRI

Decerebrate Posturing

May result from brainstem disconnection in severe DAI

Hemorrhage

Bleeding within or around the brain requiring stroke-like management

Petechial Hemorrhages

Small hemorrhages often at gray-white matter junction seen in DAI

Midline Shift Threshold

Greater than or equal to 5 mm may indicate surgery

Contraindications to Hemorrhage Surgery

GCS of 3 fixed pupils basal ganglia hemorrhage IVH or uncontrolled ICP

Increased Intracranial Pressure (ICP)

Elevated pressure in the skull risking brainstem herniation

ICP in Coma Patients

Present in approximately 80 percent at admission

Timing of ICP Elevation

Most common within the first week after TBI

Common Signs of Increased ICP

Decreased responsiveness headache vomiting papilledema and vital sign changes

Cerebral Perfusion Pressure (CPP)

Net pressure of blood flow to the brain

CPP Formula

MAP minus ICP equals CPP

Impaired Autoregulation

Loss of cerebral blood flow regulation after brain injury

MAP Below 50 mmHg

Risk of cerebral ischemia

MAP Above 150 mmHg

Risk of increased intracranial pressure

Open TBI

Penetrating injury with disrupted meninges and focal deficits

Closed TBI

Brain injury without skull penetration and intact dura

Anatomical TBI Classification

Based on open versus closed injury

Etiologic TBI Classification

Based on cause such as MVA or blunt trauma

Level of Consciousness Classification

Uses GCS or Rancho levels

Glasgow Coma Scale (GCS)

Measure of arousal and cortical function ranging from 3 to 15

GCS Components

Eye opening motor response and verbal response

Severe TBI (GCS)

Score of 8 or less on GCS

Moderate TBI (GCS)

Score of 9 to 12 on GCS

Mild TBI (GCS)

Score of 13 to 15 on GCS

Disorders of Consciousness (DOCs)

Spectrum of impaired consciousness after brain injury

Brain Death

Irreversible cessation of all brain and brainstem function

Criteria for Brain Death

Coma absent brainstem reflexes and apnea

Coma

Unarousable unresponsive state lasting up to 3 to 4 weeks

EEG in Coma

Shows no sleep-wake cycle differentiation

Unresponsive Wakefulness Syndrome (UWS)

Wakefulness without awareness and intact brainstem reflexes

Vegetative State

Older term often used for UWS

EEG in UWS

Demonstrates distinct sleep-wake cycles

Spontaneous Eye Opening

Common in unresponsive wakefulness syndrome

Persistent Vegetative State

Defined as UWS lasting one year or longer

Minimally Conscious State (MCS)

Inconsistent but purposeful responses and awareness

Awareness in MCS

Demonstrated inconsistently but clearly

Concussion (mTBI)

Functional brain disturbance without structural damage

mTBI Structural Imaging

Typically normal despite symptoms

TBI Severity Classification

Uses imaging LOC PTA and GCS criteria

Posttraumatic Amnesia (PTA)

Time from injury until continuous memory formation returns

Retrograde Amnesia

Loss of memory for events before injury

Anterograde Amnesia

Impaired ability to form new memories

Rancho Los Amigos Scale

Scale assessing cognitive recovery stages after TBI

Rancho Scale Use

Patients may demonstrate behaviors from multiple levels

Transition Between Rancho Levels

Occurs gradually not abruptly

Anoxic Brain Injury (ABI)

Diffuse brain injury caused by lack of oxygen rather than trauma

Vulnerable Areas in ABI

Hippocampus cerebellum and basal ganglia

Cheyne-Stokes Breathing

Seen in severe TBI with brainstem involvement

Cranial Nerve Damage in TBI

May result from compression or direct trauma

Paroxysmal Sympathetic Hyperactivity

Autonomic storming seen in severe TBI

Storming

Another term for paroxysmal sympathetic hyperactivity

Heterotopic Ossification (HO)

Abnormal bone formation in soft tissue after neurologic injury

Nonverbal Communication Methods

Eye blinks head nods and finger movement

Reliable Communication

Must be confirmed before use for decision-making

Behavioral Deficits Duration

Often the longest lasting impairment after TBI

Common Behavioral Changes

Disinhibition aggression apathy and low frustration tolerance

Orientation Strategies

Use explanation repetition and environmental cues

Orientation Boards

Visual aids such as calendars and whiteboards

Memory Book

Compensatory strategy used by OT and SLP

Attention Deficit Management

Simple commands limited syntax and timers

Problem Solving Impairment

Abstract reasoning commonly affected

Topographic Disorientation

Difficulty navigating environments

Pathfinding Activities

Used to assess problem solving in PT

Musculoskeletal Screening in TBI

Assess for fractures ligament injury and soft tissue damage

Integumentary Screening

Road rash and skin trauma

Cardiopulmonary Complications

Pneumothorax and other thoracic injuries

SCAT5

Standardized assessment tool for concussion

ACE Tool

CDC Acute Concussion Evaluation

Routine Imaging in mTBI

Not recommended without red flags or cervical injury

Concussion Management

Initial rest with gradual return to activity

Initial Concussion Rest

24 to 48 hours of physical and cognitive rest

Return to Activity Protocols

Used for return to work school and sport

ICP Medical Management

Head of bed elevation ventilation and osmotic agents