what is cerebral perfusion pressure (CPP)? ANS: pressure needed to ensure blood flow to the brain
CPP equation ANS: MAP-ICP
what is a normal CPP? ANS: 60-100 mmHg
a CPP <50 mmHg is associated with... ANS: ischemia
neuron death
a CPP <30 mmHG results in... ANS: ischemia --> death
_____ must be maintained when ICP is increased ANS: MAP
what maintains ICP? ANS: brain tissue
blood
CSF
what factors influence ICP under normal conditions? ANS: arterial pressure
venous pressure
,intraabdominal/intrathoracic pressure
posture
temerpature
blood gases
normal ICP ANS: 5-15 mmHg
what are the clinical manifestations of increased ICP? ANS: change in LOC
change in VS
ocular signs
decreased motor function
headache
vomiting
what is the most sensitive and reliable indicator of neurologic status? ANS: level of consciousness (LOC)
,why does increased ICP cause changes in vital signs? ANS: increasing pressure on thalamus,
hypothalamus, pons, and medulla
what vital sign change is seen with increased ICP? ANS: Cushing triad
what is Cushing triad? ANS: systolic hypertension with a widening pulse pressure
bradycardia with a full, bounding pulse
irregular respirations
systolic hypertension ANS: SBP >140 mmHg
what is a widening pulse pressure? ANS: distance between SBP and DBP is getting larger
Cushing triad usually does not appear until... ANS: ICP has been increased for some time
OR
is suddenly and markedly increased (EX: brain trauma)
Cushing triad is a... ANS: medical emergency
Cushing triad is a sign of ____ and _____ ANS: brainstem compression;
impending death
, Cushing triad is a sign of... ANS: severely increased ICP
ocular signs of increased ICP include... ANS: alterations in pupil size/reaction to light
blurred vision
diplopia
changes in extraocular eye movements
papilledema
ptosis
what is diplopia? ANS: double vision
what is papilledema? ANS: swelling of the optic disc
what is ptosis? ANS: drooping eyelid
why is headache a manifestation of increased ICP? ANS: compression of intracranial structures
nocturnal headache and/or a headache in the morning may indicate... ANS: tumor