TRAUMATIC BRAIN INJURY. Moderate and Severe Brain Injury

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1 TRAUMATIC BRAIN INJURY Moderate and Severe Brain Injury

2 Disclosures Funded research: 1. NIH: RO1 Physiology of concussion , Co-PI, $2,000, American Medical Society of Sports Medicine: RCT of Aerobic exercise, Co- PI,$400,000.

3 Purpose Provide diagnostic criteria for moderate and severe traumatic brain injury (TBI) To describe the mechanics and pathophysiology of traumatic brain injury Discuss the cognitive and behavioral implications of TBI

4 Definition Injury to the brain as a result of an external force Closed (acceleration/deceleration) injury Diffuse injury Coup contre coup injury Closed (blunt force trauma) Open Focal Gun shot/ Phineas Gage More likely to cause death Have better general outcomes Hypoxia

5 Diffuse axonal injury Most vulnerable to shearing are the long axons the ones that connect different parts of the brain End result is loss of higher order cognitive functions

6 Coup Contre-Coup Contusions Front and back will be injured if head was moving forward or backward at the time of injury Sideways coup contrecoup in side way injury

7 Coup contre coup Backward or Forward injury: Scraping of the cerebrum over the sphenoid bone and the sharp protrusions is especially damaging to the ventromedial portion of the prefrontal cortex: Emotion disregulation

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9 Rotational effect damages brain stem Probably the leading explanation for coma (alertness) and respiration difficulties

10 Brain swelling is rapid and severe Brain pushes through all openings especially the foramen magnum, and all other entrances for blood vessels Affects brain stem and blood supply Edema

11 Hypoxia/Anoxia Reduced blood/oxygen supply due to reduced respiration (brain stem involvement; chest injury) Reduced blood/oxygen supply due to edema Vascular contraction as a result of extra cellular potassium

12 Hemorrhage Usually the result of damage to the surrounding tissue May result from fracture Usually many tiny little hemorrhages

13 Acute Evaluation of Brain Injury Vital signs Glasgow coma scale Retrograde amnesia Post traumatic amnesia CT/MRI Rancho Scale

14 Glasgow Coma Scale The GCS is scored between 3 and 15, 3 being the worst, and 15 the best. It is composed of three parameters : Best Eye Response, Best Verbal Response, Best Motor Response, as given below : Best Eye Response. (4) No eye opening. Eye opening to pain. Eye opening to verbal command. Eyes open spontaneously. Best Verbal Response. (5) No verbal response Incomprehensible sounds. Inappropriate words. Confused Orientated Best Motor Response. (6) No motor response. Extension to pain. Flexion to pain. Withdrawal from pain. Localising pain. Obeys Commands.

15 Rancho Los Amigos Scale No response Generalized response Localized response Confused-Agitated (Patient is confused and agitated) Confused inappropriate Confused appropriate Automatic Purposeful

16 Medical Issues Nutritional status and requirements, with transition from enteral to oral feeding as dysphagia resolves and as protection of the airway during swallowing becomes consistently apparent Neuroendocrine complications (eg, inappropriate secretion of antidiuretic hormone, dysautonomia, cerebral salt-wasting) Pulmonary complications, including attempts to decannulate the patient with a tracheostomy, where feasible, along with prevention of static pneumonia and pulmonary embolism Balanced, regulated bladder and bowel function (achieved with a manageable routine for elimination) Late intracranial complications of traumatic brain injury (eg, posttraumatic hydrocephalus, subdural empyema, meningitis, traumatic aneurysm, dissection)(12) Posttraumatic seizure risk and hazards of anticonvulsant prophylaxis Complications that limit voluntary motility (eg, spasticity, contracture, impaired motor control) Behavioral and emotional dysfunction associated with brain injury (eg, excessive agitation, depression) Communication (sooner the better to have the individual begin to hear about the things that matter e.g family, news, sports) Attention systems (benefit from a quiet place).

17 Epidemiology Most common injury is closed head injury Most common cause is automobile crashes (Peek age is 16 to 36) 2 nd most common is falls especially for children and the elderly Good news is that serious brain injury rates are declining Most common cause of open head injury is gunshot (interpersonal crime) Bad news is that gun shot injuries are increasing Most common cause of hypoxia is heart failure, near drowning, attempted hanging, CO2 poisoning Males outnumber females 3 to 1 TBI is most common cause of death among people under 40

18 Outcomes Physical motor difficulties. Cerebellum is often damaged so one often sees a characteristic gait and inability to coordinate reaching. Somatosensory difficulties: Usually hypersensitivity to touch. Autoregulatory problems such as temperature. Disorientation. Cognitive problems: All aspects of cognition can be affected. Higher order cognitive skills most vulnerable e.g. Reading and comprehension. Memory and attention very vulnerable. Behavior problems: Impulse control issues, initiation issues, agitation, social inappropriateness. Executive Function issues: planning, problem solving, awareness, abstract thinking Personality changes: change in empathy. Big change in self confidence.

19 Predictors of Outcome GCS and length of coma is predictor of (a) survival, and (b) physical motor difficulties PTA is predictor of cognitive difficulties

20 Point After Damage is not random. Vulnerable structures include, Prefrontal cortex, especially the orbital-frontal lobe Temporal lobes Limbic system, including hippocampus Hypothalamus Long axons