1. Primer on Moderate – Severe TBI
Incidence
Pathophysiology
Neuropsychological deficits
Outcome

2. Traumatic Brain Injury
According to the CDC, in 2013, there were 2.5 million ED visits for some type of TBI in the US.
In 2013, there were approx. 50,000 deaths due to TBI.

3. Traumatic Brain Injury
Causes: May occur in motor vehicle accidents, bicycle accidents, falls, assaults, contact sports, combat (blast injury).

7. Traumatic Brain Injury
Mechanism of TBI
(1) Direct blow or trauma to the head (the head being struck by an object; the head striking an object); (2) indirect blow: acceleration/deceleration forces transmitted to the head from physical trauma/blow; (3) external force (blast wave; atmospheric pressure waves) passing through or impacting the brain that results in various types of structural brain damage and physiological disruption of brain functioning resulting in various deficits and impairments in one’s neurological, physical, cognitive and behavioral status.

9. Traumatic Brain Injury
Moderate TBI
Glasgow Coma Scale score:
Post-traumatic Amnesia: > 24 hrs - < 7 days
Length of LOC: 30 min – 24 hrs
Brain abnormalities on imaging

10. Traumatic Brain Injury
Severe TBI
Glasgow Coma Scale score: 3 - 8
Post-traumatic amnesia: > 7 days
Length of LOC: > 24 hrs
Brain abnormalities on imaging

11. TBI
Pathophysiology involves two primary forms of structural damage: diffuse axonal injury, and contusions.
DAI refers to the stretching, twisting and/or tearing of axons that occurs throughout the brain that renders the axons (and by extension the neuron) either temporarily dysfunctional or permanently damaged.

12. TBI

13. TBI

14. TBI

15. TBI
DAI occurs from physical forces acting on the white matter within the brain.
Shearing force – unaligned forces pushing one part of the brain in one direction and another part of the brain in the opposite direction.
Rotational force (most salient) – the head and brain are being rotated, which causes the axons to twist resulting in either temporary or permanent damage to the axon and neuron.

16. TBI
Contusions (bruise): brain tissue damage due to diffusely spread microvascular bleeding. Occurs when the soft brain jars against the skull and bony ridges inside the skull.

18. TBI
Contusions occur most often in the prefrontal region and anterior temporal region

19. TBI Two other major pathophysiological effects of TBI
Diffuse (multifocal) vascular injury. Various physical forces (e.g., shearing and rotational forces) may cause tearing to small blood vessels, which result in multiple small hemorrhages.

20. TBI Widespread neurochemical and neurometabolic dysfunction.
Disruption/dysregulation of the chemistry involved in cellular functioning (sodium – potassium pump).
Disruption of ATP, fuel of cellular energy (adenosine triphosphate)
Disruption/dysregulation of glucose metabolism.

21. TBI
Chemical imbalances: For example, glutamate, an excitatory neurotransmitter, is released after TBI.
Too much glutamate will excessively stimulate neurons leading to metabolic exhaustion or to the formation of free radicals with toxic effects on the nerve cell.

22. TBI
In all cases of moderate and severe TBI, the primary pathophysiology include:
Diffuse axonal injury
Contusions
Diffuse micro/small vessel injury
Widespread cellular dysfunction, neurochemical dysregulation, neurometabolic disruption, neurotransmitter imbalances.

23. TBI
There can also be secondary or delayed consequences from a TBI, such as:
Hematoma
Infection
Anoxia/hypoxia: insufficient oxygen to the brain
Seizures
Raised intracranial pressure

24. TBI
It has been estimated that in cases of severe TBI there are hundreds of millions to a couple - few billion neurons that are directly temporarily dysfunctional or permanently damaged.

25. TBI
TBI is a diffuse, multifocal brain injury. There is widespread brain damage.

26. Neuropsychological Effects
Post-acute consequences
Wide ranging outcomes
Wide ranging patterns of residual cognitive-behavioral deficits.
In Moderate and severe TBI, there is some range and magnitude/degree of residual neurological, physical, functional, cognitive, and/or behavioral deficits.

27. Attention Shorter attention span Distractibility
Impaired divided attention
Impaired sustained attention
More prone to errors
Difficulty multitasking
Attention fluctuates per cognitive load and environmental demands

28. Memory Episodic memory impairment
Deficits in both encoding and retrieval
Free recall < cued recall < recognition

29. Language Typically do not see classic aphasia syndromes in TBI.
Less likely to see significant language deficits. Primary language zones are typically less damaged in TBI.
Word finding problems.
Need to re-read information
Need more time to comprehend info

30. Language
Difficulty writing lengthy or complex papers, owing to deficits in the interface of language and executive functions.

31. Speed of Information Processing
Slower processing information
Slower completing cognitive tasks

32. Cognitive Fatigue
Lowered cognitive stamina and endurance.

33. Executive Cognitive Functions
Deficits in
Abstract Reasoning
Problem solving
Organization
Planning
Decision making

34. Executive Behavioral Functions
Impaired self-regulation of behavior: A person’s ability to modulate, activate and/or depress cognitive, behavioral and emotional responses in order to achieve a desired outcome.
Impaired self-monitoring of behavior: A process of tracking, evaluating and correcting one’s actions and behavior.

35. Executive Behavioral Deficits
Behaviors of excess
Disinhibition
Impulsivity
Quick to get irritable or agitated
Social skills – Verbose, interruptions

36. Executive Behavioral Deficits
Behaviors of inaction
Apathy / Adynamia
Drive, motivation
Initiation
Follow through

37. Awareness
Unawareness may be defined as a global to discrete, severe to mild, lack of recognition, experience or perception of deficits that is neurologically mediated.
Thus, there is some degree of disparity between one’s self-appraisal vs their actual level of functioning.

38. Emotional – Psychological Issues
Depressed mood
Grief
Anger/frustration
Uncertainty
Change in self-identity
Loss of purpose and meaning

39. Outcome

40. Outcome