the central nervous system is made up of:
1
2
the brain
the spinal cord
plates of large, flat bones that are fused together to form a helmetlike covering is called the ________.
cranial skull
the floor of the skull, made up for many seperate pieces of bone and is the weakest part of the skull.
basilar skull
within the skull, the brain is cushioned in a dense, serous substance called _________. produced by the brain, this fluid protects the brain and spinal cord against impact.
cerebrospinal fluid CSF
layers of tissue protecting the brain. they include the duramater, the arachnoid, and the pia matter.
meninges
outermost layer of tissue that encloses the brain and is composed of a double layer of tough, fibrous tissue.
dura mater (“hard mother”)
layer of tissue that is in contact with the brain.
pia mater (“soft mother”)
bleeding that occurs between the dura mater and the skull is called ______ and usually involves the brains outermost arteries.
epidural
the largest part of the brain, comprises three-fourths of the brains volume. responsible for most conscious and sensory functions, the emotions, and personality.
cerebrum
part of the brain that controls equilibrium and coordinates muscle activity.
cerebellum
the most primitive and best protected part of the brain. controls most automatic functions of the body, including cardiac, respiratory, vasomotor (blood pressure), and other functions vital to life
brainstem
injuries to the brain that result from shearing, tearing, and stretching of nerve fibers is called a _______ (DAI)
diffuse axonal injury
causes some disturbance in brain function ranging from momentary confusion to complete loss of responsiveness, and it usually causes h/a.
concussion
s/s:
momentary confusion
confusion that lasts several minutes
inability to recall the incident and, sometimes, the period just before it and right after it
repeated questioning about what happened
mild to moderate irritability or resistance to treatment
combativeness
inability to answer questions or obey commands appropriately
n/v
restlessness
concussion
s/s: decreasing mental status or unresponsiveness paralysis unequal pupils vomiting alteration of vital signs profound personality changes
brain contusion
a collection of blood between the dura mater and the arachnoid layer of the brain.
subdural hematoma
s/s: weakness or paralysis to one side of the body deterioration in level of responsiveness vomiting dilation of one pupil abnormal resp or apnea possible increasing systolic bp decreasing pulse rate h/a seizures confusion personality changes
subdural hematoma
bleeding between the dura mater and the skull
epidural hematoma
s/s loss of responsiveness followed by return and the rapid decline decreasing mental status severe headache fixed dilated pupil seizures increasing systolic bp decreasing hr vomiting apnea or abnormal breathing systolic hypertension and bradycardia posturing
epidural hematoma
s/s dilated or sluggish pupil on one side weakness or paralysis sever alteration in consciousness abnormal posturing abnormal ventilation pattern crushing reflex ( increased systolic and decreased HR)
brain herniation
same or similar reaction of the unstimulated pupil when the other pupil is stimulated, as when a light is shined into one pupil and both pupils contract
consensual reflex
a protective reflex by the body to maintain perfusion of the brain in a head-injured pt with increased intracranial pressure. the systolic BP increases, HR decreases, and the resp pattern changes. this syndrome indicates severe head injury.
cushing reflex
s/s AMS decreasing mental status irregular breathing patteren cushing reflex obvious signs of injury visible damage to skull pain, tenderness, or swelling at site of injury blood CSF battle sign absent motor function n/a unequal pupil size with AMS diplopia - double vision possible seizures nonpurposeful response to painful stimuli retrograde amnesia antegrade amnesia
head injury