Week 6: Trauma and Increased intracranial pressure, and Headache Flashcards
Define concussion.
Altered consciousness as a result of closed head injury (transient disturbance in neuronal function)
- no gross or microscopic parenchymal abnormalities
- no CT or MRI findings
Define contusion
A bruise of the brain where sudden head deceleration causes the brain to impact on bony prominences (temporal, frontal, occipital)
What are characteristics of a linear skull fracture.
- substantial force
- relation to suture line
- relation to vascular structure
What is a comminuted skull fracture?
-multiple fragments
What is an open or compound fracture?
-fracture underlying a scalp laceration, predisposes to infection
What is a depressed skull fracture?
-fragments indented greater than width of inner and outer tables. laceration of underlying dura or brain my result in seizure, focus, or focal neurologic deficits, and infection
What is the exception or contraindication for surgery in a depressed skull fracture?
If depressed fracture is overlying and depressing a dural sinus, may be dangerous to elevate
What is the Monroe-Kellie Doctrine?
Sum of the intracranial volumes of BLOOD, BRAIN, and CSF is other components is constant. Increase in any one of these is offset by a decrease in another
-since volumes are contained in rigid container
What is normal cerebral perfusion pressure? How is CPP calculated? What is normal intracranial pressure?
- normal is >50mm Hg
- CPP=mean arterial pressure-intracranial pressure
- normal ICP>20 mm Hg in adults
What are the characteristics of epidural hematomas?
- between dura and skull
- lens shaped
- restricted by sutures where dura are tightly adhered
- arterial bleeding
- bleeding from middle meningeal artery
What are the characteristics of subdural hematomas?
- between dura and arachnoid
- crescent shaped
- venous bleeding
- bridging veins
What are the characteristics of intracerebral bleeds?
- in parenchyma
- delayed from contusion
- penetrating
- generally more focal deficits than extra cerebral hematomas
What is Cushing’s Triad? (signs of increased intracranial pressure)
- Hypertension
- bradycardia
- respiratory irregularity
What are the characteristics of a tentorial herniation? (uncal)
- lateralized mass
- unilateral compression of brainstem
- compressed 3rd nerve
- compressed cerebral penduncle
What are treatments for increased intracranial pressure?
- hyperventilation: removes CO2, makes body believe has more oxygen, causes constriction of the vessels
- mannitol (pharmacological)
- Catheter to remove CSF fluid
- barbiturates for vasoconstriction
- hemicraniectomy
- ventriculostomy