NURC 424 Exam 3 Chpt 56 Questions And Accurate Answers
Acute Intracranial Problem - Answer Untreated elevated ICP → brainstem compression
and herniation (often irreversible). Compression of brain stem or cranial nerves may be
fatal. Brain stem compression that is not relieved causes resp arrest d/t medulla
compression.
Intracranial regulation-Answer Monro-Kellie doctrine = 3 components must remain at a
relatively constant vol. If the vol of any 1 of the 3 components increases and the vol from
another component is displaced, the total intracranial vol will not change.
Increased intracranial pressure-Answer hydrostatic force measured in the brain.
Increases risks of brain ischemia and infarction, and is associated with a poor
prognosis.
Mechanism of Increased Intracranial Pressure-Answer Edema distorts brains tissue ->
increased ICP -> hypoxia & acidosis. Increased blood in cranial compartment ->
increased ICP. Increased amount of CSF -> increased ICP.
Cerebral Edema-Answer Increased accumulation of fluid in the extravascular spaces of
brain tissue -> increased tissue vol -> increased ICP
Vasogenic Cerebral Edema - Answer Most common. Occurs mainly in white matter.
Large molecules leak from capillaries into surrounding extracellular space. Causes:
brain tumors, abscesses, ingested toxins. S/Sx: HA, Decreased LOC, coma, focal
neurogenic deficits.
Cytotoxic Cerebral Edema - Answer Integrity of cell membrane disrupted. Fluid and
proteins shifted into cells, yet the blood-brain barrier is intact. Causes: destructive
lesions or trauma to brain tissue leading to cerebral hypoxia or anoxia as well as SIADH
secretion.
, Interstitial Cerebral Edema - Answer This often occurs as a result of hydrocephalus.
Over production of CSF, obstruction of CSF flow, and/ or the inability to reabsorb CSF
result in ventricular enlargement
Clinical Manifestations of increased intracranial pressure - Answer Change in LOC
Pressure on reticular activating system RAS (brain stem) or cerebral cortex. Look for
changes in consciousness, resp, urination
· Change in Vital Signs Systolic HTN w/ widening pulse pressure, bradycardia full and
bounding, irregular respirations = Cushing Triad. Medical Emergency, not seen until
later w/ ICP
· Ocular Signs Papilledema- increased CSF -> swelling; Pupil, fixed and dilated- d/t
pressure on CN3 · Decreased Motor Function Contralateral hemiparesis; Decorticate-
internal rotation of arms w/ flexion of elbows, wrists, and fingers; Decerebrate- arms
stiffly extended, adducted, and hyperpronated; legs are hyperextended w/ plantar
flexion; Decerebrate= more serious damage.
• Headache Stretching or distortion of meninges or walls of large blood vessels. Morning
HA or nocturnal HA are of greatest concern.
• Vomiting Pressure on emetic center in medulla (often projectile and not associated w/
food). Not associated w/ nausea.
Complications of Increased Intracranial pressure - Answer Inadequate cerebral
perfusion and herniation
Diagnostic Studies for increased ICP VS, neuro checks, ICP measurements,
skull/chest/spinal XRay, Imaging, Labs CBC, coag, elec, creatinine, ABG, ammonia,
toxicology, CSF analysis of glucose/protein/cells
Indications for Intracranial Pressure Monitoring hemorrhage, stroke, tumor, infection,
TBI, GCS < 8, abnormal imaging results
Ventriculostomy - Answer cath interested into lateral ventricle and attached to external
transducer. Measures pressure, allows for aspiration, allows for drug administration.
Trasnducer must be at same level of foramen of Monro.
Acute Intracranial Problem - Answer Untreated elevated ICP → brainstem compression
and herniation (often irreversible). Compression of brain stem or cranial nerves may be
fatal. Brain stem compression that is not relieved causes resp arrest d/t medulla
compression.
Intracranial regulation-Answer Monro-Kellie doctrine = 3 components must remain at a
relatively constant vol. If the vol of any 1 of the 3 components increases and the vol from
another component is displaced, the total intracranial vol will not change.
Increased intracranial pressure-Answer hydrostatic force measured in the brain.
Increases risks of brain ischemia and infarction, and is associated with a poor
prognosis.
Mechanism of Increased Intracranial Pressure-Answer Edema distorts brains tissue ->
increased ICP -> hypoxia & acidosis. Increased blood in cranial compartment ->
increased ICP. Increased amount of CSF -> increased ICP.
Cerebral Edema-Answer Increased accumulation of fluid in the extravascular spaces of
brain tissue -> increased tissue vol -> increased ICP
Vasogenic Cerebral Edema - Answer Most common. Occurs mainly in white matter.
Large molecules leak from capillaries into surrounding extracellular space. Causes:
brain tumors, abscesses, ingested toxins. S/Sx: HA, Decreased LOC, coma, focal
neurogenic deficits.
Cytotoxic Cerebral Edema - Answer Integrity of cell membrane disrupted. Fluid and
proteins shifted into cells, yet the blood-brain barrier is intact. Causes: destructive
lesions or trauma to brain tissue leading to cerebral hypoxia or anoxia as well as SIADH
secretion.
, Interstitial Cerebral Edema - Answer This often occurs as a result of hydrocephalus.
Over production of CSF, obstruction of CSF flow, and/ or the inability to reabsorb CSF
result in ventricular enlargement
Clinical Manifestations of increased intracranial pressure - Answer Change in LOC
Pressure on reticular activating system RAS (brain stem) or cerebral cortex. Look for
changes in consciousness, resp, urination
· Change in Vital Signs Systolic HTN w/ widening pulse pressure, bradycardia full and
bounding, irregular respirations = Cushing Triad. Medical Emergency, not seen until
later w/ ICP
· Ocular Signs Papilledema- increased CSF -> swelling; Pupil, fixed and dilated- d/t
pressure on CN3 · Decreased Motor Function Contralateral hemiparesis; Decorticate-
internal rotation of arms w/ flexion of elbows, wrists, and fingers; Decerebrate- arms
stiffly extended, adducted, and hyperpronated; legs are hyperextended w/ plantar
flexion; Decerebrate= more serious damage.
• Headache Stretching or distortion of meninges or walls of large blood vessels. Morning
HA or nocturnal HA are of greatest concern.
• Vomiting Pressure on emetic center in medulla (often projectile and not associated w/
food). Not associated w/ nausea.
Complications of Increased Intracranial pressure - Answer Inadequate cerebral
perfusion and herniation
Diagnostic Studies for increased ICP VS, neuro checks, ICP measurements,
skull/chest/spinal XRay, Imaging, Labs CBC, coag, elec, creatinine, ABG, ammonia,
toxicology, CSF analysis of glucose/protein/cells
Indications for Intracranial Pressure Monitoring hemorrhage, stroke, tumor, infection,
TBI, GCS < 8, abnormal imaging results
Ventriculostomy - Answer cath interested into lateral ventricle and attached to external
transducer. Measures pressure, allows for aspiration, allows for drug administration.
Trasnducer must be at same level of foramen of Monro.
