NURC 424 Exam 3 Chpt 56 Study
Guide
Acute Intracranial Problem - Answer Untreated elevated ICP -> brainstem compression
and herniation (often irreversible). Compression of brain stem or cranial nerves can 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.
Mechanisms 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 Disruption in integrity of cell membrane. Proteins
and fluid shifts into cells, but blood brain barrier is intact. Causes: destructive lesions or
trauma to brain tissue, resulting in cerebral hypoxia or anoxia and SIADH secretion.
Interstitial Cerebral Edema - Answer Usually a result of hydrocephalus. Excess CSF
production, obstruction of flow, or inability to reabsorb CSF cause 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)
, · Decrease in Motor Function Contralateral hemiparesis. Decorticate (internal rotation of
arms w/ flexion of elbows, wrists, and fingers) and Decerebrate (arms stiffly extended,
adducted, and hyperpronated; legs are hyperextended w/ plantar flexion) posturing.
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 - Answer 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 - Answer 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.
Fiberoptic Cath - Answer has transducer in tip of cath. Placed in ventricle and measure
pressure.
Air pouch/pneumatic technology - Answer has air pouch in cath which measures the
pressure changes. If CSF drain is in place, must be closed for 6 min to get accurate
reading. Normal ICP looks like downward staircase. If increased ICP, P2 raises above
P1. Infection is serious complication to ICF monitoring. Contributing factors =
monitoring > 5 days, using ventriculostomy, CSF leak, concurrent system infection.
Cerebrospinal Fluid Drainage - Answer Done if ICP > 20mmHg. Rate is set by provider,
can be continuous or intermittent. CSF is produced at a rate of 20-30mL/hr. About
150mL in body. Complication include ventricular collapse, infection, herniation,
subdural herniation formation from rapid decompression.
Cerebral Oxygenation monitoring - Answer LICOX/Neurovent Caths placed in healthy
white matter. Normal PbtO2 = 20-40mmHg. Cooler brains (96.8/36) temps may produce
better outcomes.
§ Interprofessional Care Goals: 1. Identify/Tx underlying cause. 2. Sup
Interprofessional Care for increased ICP - Answer Goals: 1. Identify/Tx underlying
cause. 2. Support brain Fx. Hx is very important of determining underlying cause.
Maintain O2 to prevent secondary injury. ABGs guide O2 therapy.
Guide
Acute Intracranial Problem - Answer Untreated elevated ICP -> brainstem compression
and herniation (often irreversible). Compression of brain stem or cranial nerves can 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.
Mechanisms 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 Disruption in integrity of cell membrane. Proteins
and fluid shifts into cells, but blood brain barrier is intact. Causes: destructive lesions or
trauma to brain tissue, resulting in cerebral hypoxia or anoxia and SIADH secretion.
Interstitial Cerebral Edema - Answer Usually a result of hydrocephalus. Excess CSF
production, obstruction of flow, or inability to reabsorb CSF cause 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)
, · Decrease in Motor Function Contralateral hemiparesis. Decorticate (internal rotation of
arms w/ flexion of elbows, wrists, and fingers) and Decerebrate (arms stiffly extended,
adducted, and hyperpronated; legs are hyperextended w/ plantar flexion) posturing.
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 - Answer 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 - Answer 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.
Fiberoptic Cath - Answer has transducer in tip of cath. Placed in ventricle and measure
pressure.
Air pouch/pneumatic technology - Answer has air pouch in cath which measures the
pressure changes. If CSF drain is in place, must be closed for 6 min to get accurate
reading. Normal ICP looks like downward staircase. If increased ICP, P2 raises above
P1. Infection is serious complication to ICF monitoring. Contributing factors =
monitoring > 5 days, using ventriculostomy, CSF leak, concurrent system infection.
Cerebrospinal Fluid Drainage - Answer Done if ICP > 20mmHg. Rate is set by provider,
can be continuous or intermittent. CSF is produced at a rate of 20-30mL/hr. About
150mL in body. Complication include ventricular collapse, infection, herniation,
subdural herniation formation from rapid decompression.
Cerebral Oxygenation monitoring - Answer LICOX/Neurovent Caths placed in healthy
white matter. Normal PbtO2 = 20-40mmHg. Cooler brains (96.8/36) temps may produce
better outcomes.
§ Interprofessional Care Goals: 1. Identify/Tx underlying cause. 2. Sup
Interprofessional Care for increased ICP - Answer Goals: 1. Identify/Tx underlying
cause. 2. Support brain Fx. Hx is very important of determining underlying cause.
Maintain O2 to prevent secondary injury. ABGs guide O2 therapy.
