Traumatic Brain Injury - Lecture Part 1 (PDF)

PT 351 PT IN NEUROLOGY (1) Traumatic Brain Injury PART 1 Dr. Ali Bani Ahmed PT, DPT, CPT, CKTP, CES, CDNP, PhD Traumatic Brain Injury  Traumatic Brain Injury is… ▪ Injury to the brain caused by external force. ▪ Injury to the head from a blunt or pene...

PT 351 PT IN NEUROLOGY (1) Traumatic Brain Injury PART 1 Dr. Ali Bani Ahmed PT, DPT, CPT, CKTP, CES, CDNP, PhD Traumatic Brain Injury  Traumatic Brain Injury is… ▪ Injury to the brain caused by external force. ▪ Injury to the head from a blunt or penetrating object ▪ Injury from rapid movement of the head that causes back and forth movement inside the skull ▪ The injury is not caused by a degenerative or congenital condition.  Causes of TBI In DV Populations Blow to the head Pushed with any object against the wall or other Strenuous solid object shaking of body Punched in the face Falling and hitting your Use of firearms head Strangled Near drowning  Scope of the Problem ▪ 2 million people sustain a brain injury every year ▪ Every 15 seconds someone sustains a TBI ▪ Leading cause of death until age 44 ▪ 4th leading cause of death overall ▪ Each day 5,500 individuals sustain a TBI  TBI Ages Population incidence of 100/100,000 ▪ Peaks at below 5 years, 15-24 yrs, +70 yrs ▪ Maximum peaks are: ▪ 133/100,000 in the 15-24 years age group ▪ 165/100,000 in the 65+ years age group  TBI Gender Males are two times more likely than females to sustain a brain injury. The highest rate of injury is for males age 15-24.  Traumatic Brain Injury is… ▪ Brain injury results from: ▪ Direct injury to brain tissue ▪ External forces applied to outside of skull transmitted to the brain ▪ Movement of brain inside skull  Two varieties of TBI Open head injury Penetration of the head Common causes: severe fall, gunshot, assault, vehicle accident Closed head injury No open head wound; brain damaged internally Common causes: Falls, vehicle accidents, sports accidents  Two varieties of TBI Open head injury Penetration of the head Common causes: severe fall, gunshot, assault, vehicle accident  Two varieties of TBI Closed head injury No open head wound; brain damaged internally Common causes: Falls, vehicle accidents, sports accidents  Traumatic Brain Injury is… ▪ Thus the mechanisms of closed head injury are either due to: ▪ Contact-phenomena (usually resulting in focal lesions) ▪ acceleration/deceleration phenomena (principally causing diffuse axonal injury (DAI). ▪ It is important to realize that severe brain damage can occur in the absence of easily visible external injury and vice versa, and that focal and diffuse lesions may occur in isolation or be combined.  Two varieties of Injury Focal Injury Diffuse  Injury is highly concentrated  Injury is not pinpointable in a particular area  Usually from closed  Usually from open head head sudden rotational injury and/or brain deceleration. (e.g. Head penetration hitting the airbag)  Symptoms closely related  Symptoms may not be to functions governed by evident, since location of affected area of brain. injury is unknown.  Easier to detect using  Almost impossible to medical imaging technology detect Types of TBI Damage Types of TBI Damage (Primary brain damage)  Localized damage to the brain under the site of the impact (Local injury) or under the site of impact and the directly opposite site due to brain bouncing (Coup-countercoup injury).  Symptoms depends on the lesion site  Types of TBI Damage (Primary brain damage)  Primary injuries result immediately from the initial trauma.  Primary injury occurs at the moment of trauma and includes contusion, damage to blood vessels, and axonal shearing, in which the axons of neurons are stretched and torn.  The blood brain barrier and meninges may be damaged in the primary injury, and neurons may die Types of TBI Damage (Primary brain damage)  Types of head injury (Secondary Damage) Results from processes initiated by the trauma. Occurs in the hours and days following the primary injury and plays a large role in the brain damage and death that results from TBI. Unlike in most forms of trauma a large percentage of the people killed by brain trauma do not die right away but rather days to weeks after the event. In addition, rather than improving after being hospitalized as most patients with other types of injuries do, about 40% of people with TBI deteriorate. This is often a result of secondary injury, which can damage neurons that were unharmed in the primary injury  Types of head injury (Secondary Damage) ❑ Changes in the blood flow to the brain ▪ Ischemia (insufficient blood flow) cerebral hypoxia (insufficient oxygen in the brain) ▪ Hypotension (low blood pressure) ▪ Cerebral edema (swelling of the brain) ❑ Raised intracranial pressure (the pressure within the skull) ▪ If intracranial pressure gets too high, it can lead to deadly brain herniation, in which parts of the brain are squeezed past structures in the skull. Types of head injury (Secondary Damage)  Severity of TBI Moderate to Severe Mild ▪ 15% of all TBIs ▪ 85% of all TBIs ▪ Typically hospitalized ▪ Seen ER or MD office ▪ “Identified as a TBI” ▪ “Identified as a ▪ Known and followed concussion” by medical community ▪ Not followed by medical community in many cases  Moderate to Severe TBI ▪ Documented loss of consciousness ▪ Potential skull fractures ▪ Significant period (days to weeks) of coma ▪ Significant loss of information for a period of time post event (post-traumatic amnesia) ▪ Significant and chronic cognitive, physical and behavioral changes Moderate to Severe TBI  Mild TBI/Concussion ▪ Headaches ▪ Dizziness ▪ Slowed processing ▪ Forgetfulness ▪ Fatigue ▪ Sensitivity to noise and lights  Mild TBI/Concussion ▪ 85% have full recovery within 3-6 months post event ▪ 15% experience chronic symptoms which significantly interfere with their daily functioning How the brain works... How the brain might look after a TBI... How the brain works... How the brain works... What are the most common problems after TBI  Neuromuscular ▪ Abnormal tone ▪ Paresis/paralysis ▪ Impaired balance ▪ Sensory impairments  Cognitive Changes in “Executive Functioning” cognitive control of behavior Difficulty planning/ setting Difficulty problem goals solving Problems being Difficulty organized prioritizing Difficulty Impaired insight and being safety awareness flexible  Communication deficits ▪ Communication ▪ Impaired pragmatics: Difficulty finding the right words, naming objects ▪ Receptive/fluent aphasia (Temporal lobe) ▪ Expressive/non fluent aphasia (Frontal lobe) ▪ Dysarthria (cerebellum) ▪ Impaired reading comprehension ▪ Impaired written expression  Emotional/Behavioral/Social Changes Anxiety Increased Depression impulsivity Irritability/ agitation Difficulty with self initiation Socially (Apathy) inappropriate behavior Impatience Intolerant Inability to get Rapid loss of along with others emotional Before-after control contrasts (short fuse) Self-monitoring Increased self focus  Changes after a Brain Injury The most important things to remember: ▪ No two brain injuries are exactly the same ▪ The effects of a brain injury depend on such factors as cause, location and severity  Long Term Challenges Post TBI ▪ Vocational and/or school failure ▪ Family life/social relationships collapse ▪ Increased financial burden on families and social service systems ▪ Alcohol and drug abuse ▪ Chronic depression/anxiety