Anterior spinal cord injury
Caused by ischemic injury to the anterior aspect of spinal cord due to occlusion of anterior spinal artery, which is most commonly occur as a consequence of non traumatic process, although it can be traumatic. The anterior two-thirds of the spinal cord contains corticospinal and spinothalamic tracts, which are affected in this syndrome.
Brown-Sequard cord injury
Result of a hemicord lesion (i.e damage or impairment to the left or right side of the spinal cord).
Central cord injury
The most common type of incomplete spinal cord injury, accounting for ~10% of all spinal cord injuries.
Most often occurs in older persons with degenerative disk disease; however, it may also be seen in younger persons who sustain trauma to the cervical spine, typically after an athlete spears another with their head, or a diving injury.
Cerebral perfusion pressure is calculated
CPP = MAP - ICP
Increasing ICP is most easily seen with what clinical change?
Changing level of consciousness
What is Doll’s eyes reflex? What does it indicate?
Ability to stay fixed on a point when head is turned (eyes move opposite of head direction)
Absence indicates midbrain/pons injury
What is Brudzinski’s sign? What does it indicate?
A stiff neck that causes knees/hips to bend when neck is flexed.
Meningitis or subarachnoid hemorrhage
A trauma patient with hypotension, normal HR, and pink/dry skin may have what type of shock?
Signs of uncal herneation include
(1) Abnormal posture and poor GCS. There may be pupillary dilation and loss of light reflex due to direct compression of the oculomotor nerve.
What is a transcalvarial herneation?
(4) The brain herneates through an open skull fracture (or surgical site)
What is a cingulate (subfalcine) herneation?
(3) The brain (frontal lobe) is scraped under part of the falx cerebri, the dura mater at the top of the head between the two hemispheres of the brain.
This can cause abnormal blood flow, leading to a dangerous increase in ICP
Vomiting from a head injury is due to increased pressure on what structure?
The area postrema in the medulla oblongata
Normal cerebral perfusion pressure is
Normal ICP is
What two “electrolytes” are most important to maintain in a head-injured patient
glucose and sodium
Cushing’s triad typically has what findings?
Hypertension / wide pulse pressure
Abnormal respiratory pattern
An epidural hematoma usually involves what type of blood vessel
A subdural hematoma usually involves what type of blood vessels?
A subarachnoid hematoma typically involves what type of blood vessels?
Usual presentation for a subarachnoid hemorrhage is
Sudden, severe headache
Usual presentation for an epidural hematoma is
Loss of consciousness followed by a lucid period
What is Babinski’s reflex? What does it indicate?
- Plantor extensor reflex
- Is present/absent, not normal/abnormal
- Indicates upper motor neuron (brain stem) injury (age >2)
Bell’s Palsy affects what cranial nerve?
How does Bell’s palsy differ from acute CVA?
Bell’s Palsy always affects upper and lower face without other symptoms.
CVA affects lower face with other, associated symptoms.
What cranial nerves controls eye movement, pupil dilation, and pupil accomodation?
CN III (oculomotor)
CN IV (trochlear)
CN VI (abducens)
What cranial nerve transmits visual informaition?
CN II (optic)
What cranial nerve controls the sense of smell?
CN I (olfactory)
What cranial nerve controls facial sensation and chewing?
CN V (trigeminal)
What cranial nerve controls movement of the facial muscles?
CN VII (facial)
What cranial nerve controls hearing and position/balance?
CN VIII (vestibulocochlear)
What cranial nerve controls taste and salivation?
CN IX (glossopharyngeal)
What cranial nerve controls the ability to swallow, as well as parasympathetic innervation to much of the body?
CN X (vagus)
What cranial nerve controls the ability to raise the shoulders and turn the head?
CN XI (accessory)
What cranial nerve controls the ability to move the tongue?
CN XII (hypoglossal)
What is Guillan-barre syndrome and how does it typically present?
Acute inflammatory demyelinating polyneuropathy - an infectous process of the peripheral nervous system that causes ascending paralysis
What is myasthenia gravis and how does it typically present?
An autoimmune disorder that destroys acetylcholine receptors in postsynaptic neuromuscular junctions, causing transient weakness and fatigue
excessive pupil dilation
excessive pupil constriction
How does decorticate posturing present, and what does it indicate?
Damage to cerebral hemispheres, thalmus, or midbrain
How does decerebrate posturing present, and what does it indicate?
Damage to midbrain, brainstem, or cerebellum
Progression from decorticate to decerebrate posturing often indicates
uncal (1) or tonsillar (6) herneation