Increased ICP (939-940, chart 941)
Normal ICP 10-15 mmHg, pressures >20 mmHg impair cerebral circulation
IICP is leading cause of death from head trauma in pts who reach the hospital alive.
Cerebral Perfusion Pr
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Increased ICP (939-940, chart 941)
Normal ICP 10-15 mmHg, pressures >20 mmHg impair cerebral circulation
IICP is leading cause of death from head trauma in pts who reach the hospital alive.
Cerebral Perfusion Pressure (CPP)
o Blood flow required to provide adequate oxygenation & glucose for brain metabolism
o Maintenance above 70 mmHg
o CPP= MAP-ICP
MAP= (2xD) + S MAP NEEDS TO BE ATLEAST 80
3
Compensation
o First Response – CSF is shunted or displaced into the spine (compliance)
o Next – Reduction of blood volume in the brain (autoregulation)
o As ICP continues to increase cerebral perfusion decreases leading to brain tissue ischemia, edema, vasodilation
then acidosis which causes further increases ICP
o In edema remains untreated the brain may herniate into spinal canal – death from brain stem compression
Assessment Findings
o Changes in LOC – First sign of IICP is declining LOC & includes restlessness or confusion to Stuporous
W/o glucose & 02, brain shuts down. Ex. Pt knew who you were in am & now don’t remember
o Headache – Quite environment may have photophobia so keep room lights very low.
o Change in speech pattern – Aphasia, Slurred Speech
o Changes in pupil size – 2 cm change in either direction is significant, dilated or constricted, Notify Dr
Normal is 6 mm. Getting better if going back toward normal from dilated or constricted
Uneven pupils tx as IICP until proven otherwise; pinpoint - brain stem (pons) dysfunction
o Abnormal Posturing – Decorticate (flexion) or Decerebrate (extensor)
Decorticate – arms drawn to core, legs straight
Decerebrate – arms straight and stiff, pts rarely survive
o Hyperthermia – followed later by hypothermia
When hypothermic – BE CONCERNED, pressure on hypothalamus located next to brain stem
o Cardiac & respiratory rate/rhythm changes
Tachy first – Increased HR & RR before brady HR & RR
o N/V – Common in IICP
o Cushing’s Triad – Severe HTN, Widened Pulse Pressure, Bradycardia
Late response & indicates severe IICP w/loss of autoregulation, Imminent death
Systolic BP increases bc decreased blood flow to brain
Pressure on Vagus nerve and brainstem = bradycardia
Managing IICP
o Elevate HOB 30-45 degrees (unless contraindicated)
If hypotension, elevate HOB where CPP >70
o Maintain head in a midline neutral position
o Avoid sudden and acute hip or neck flexion during positioning – Log roll pt
o Avoid clustering of care (bath followed by linen change)
o Coughing and suctioning increase ICP
o Decrease cerebral edema – osmotic diuretics (mannitol) & fluid restriction
Mannitol is hypertonic- pulling fluid into vascular space- will inc. fluid output & monitor BP for HTN
Furosemide used in adjunct to reduce incidence of rebound from mannitol. Helps reduce edema &
blood volume, decrease Na uptake by the brain, & decrease production of CSF at choroid plexus.
o LOW CSF using intraventricular drain system
o Control fever w/antipyretics or cooling blanket – do not allow pt to shiver as will increase ICP
When febrile every cell in body needs more 02 and glucose
o Oxygenation – Hyperventilate on a vent to decrease CO2 which causes vasodilation
o Reduce cellular metabolic demands – barbiturates (-bital, -barbital) and/or sedation (coma)
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