Neurological Disorders - Trauma Flashcards
Brains response to secondary injury
Swelling and decreases perfusion - hypoxia - swelling - decreased perfusion
Brains initial response to bruising
Vasodilation to increase blood flow
Increases ICP
Increased ICP causes decreased blood flow
Decreased CO2 levels will cause
Hypoventilation - cerebral vasoconstriction - cerebral Ischemia (hypoxia)
Increased CO2 levels will cause
Hyperventilation - vasodilation and edema (hypoxia)
What is CPP
Cerebral perfusion pressure (70-80)
What is MAP
Mean arterial pressure (70-100)
How to calculate CPP
MAP - ICP
Early signs of ICP
Shift CSF to spinal cavity
Effective until become hypoxia
Hypoxia triggers vasodilation which adds fluid volume
Cushing reflex
Increased BP
Decreased HR
Decreased RR
Why does the BP increase with ICP
Body responds to hypoxia and activates SNS, increasing BP and HR
Why does pulse decreased when increased ICP
Baroreceptors in carotid arteries respond to increased BP and slow the heart rate
Why are respirations irregular when ICP is increased
Chemoreceptors respond to low CO2 levels from accelerated systemic circulation, and pressure on brainstem
Cerebral herniation
Brain swells and forces tissues downward through foramen magnum
What is a concussion
Mild blow to the head that causes excessive head movement
S/S of concussion
Headache, dizzy, amnesia, tinitis, light sensitivity
Cerebral contusion S/S
Prolonged unconsciousness, altered LOC, personality changes, abnormal behaviour, focal neurological signs
Basilar fracture
Fracture at the base of the skull
Accompanied with discolouration around eyes and behind ears, leaking CSF
Diffuse axonal injury
Severe blunt head trauma that’s causes stretched, shearing and tearing of nerve fibres (axons).
S/S of diffuse axonal injury
Generalized edema, subarachnoid bleeding, seizure activity, coma, vomitting
usually ends up vegetable
Anoxic brain injury
Lack of oxygen to cells usually from cardiac arrest, airway obstruction, drowing
Contrecoup injury
Occurs when rebound causes brain to impact opposite side of skull
Spinal Cord injury
Results from a fracture or dislocation of the vertebrae which stretches, compresses or tears the spinal cord
Epidural hematoma
Between skull and dura
Head trauma with loss of consciousness, lucid interval with signs of increased ICP, then rapid death
Subdural hematoma
Between dura and arachnoid, more common than epidural hematoma
