Care of the Patient Experiencing an Intracranial Dysfunction
ICP and CPP: know how to calculate, normal values and what they mean
ICP-intracranial pressure
o normal value: 5-15 mmHg
o any increase in volume or abnormal growth will increase ICP or decrease other volumes resulting in cell
death related to decreased perfusion
o 3 components
brain substance (80%)
CSF (10%)
blood (10%)
CPP-cerebral perfusion pressure
o normal value: 60-100 mmHg
o CPP is an estimate of cerebral blood flow
o intracranial HTN is a value >/=20 mmHg
o Calculation for CPP
MAP-ICP=CPP
Increased ICP:
causes
o increased brain volume
tumor or injury with cerebral edema
o increased CSF
hydrocephalus, obstruction, excess production of CSF
o increased blood
autoregulation loss, hemorrhage, vasodilation, hypercapnia, metabolic demand increase, venous
outflow obstruction
change in circulating volume from decreased Na+, hypo/hyperTN, seizures, or increased
intrathoracic pressure
o extracranial
assessment
o Glasgow Coma Scale (GCS)
normal/highest is 15 & lowest is 3
provide intracranial monitoring with a score of 3-8
o Early Responses to IICP
altered LOC
papilledema
unilateral pupil dilation
HA
vomiting
o Late Responses to IICP
paralysis & parasthesia
Cushing's Triad
systolic HTN
widening pulse pressure
bradycardia
hyperventilation (Cheyne-Stokes breathing pattern)
Herniation of the brain stem is a complication
o Cranial Nerve Testing
Pupillary- optic (2) & oculomotor (3)
Corneal-trigeminal (5) & facial (7)
, Hearing, tinnitus, & dizziness-acoustic (8)
cough & gag reflex-glossopharyngeal (9) & vagus (10)
o Comatose Patients
Oculocephalic Reflex-"Doll's Eyes"
negative reflex if eyes do not move symmetrically or stare straight ahead when head is
moved
C-Spine must be cleared before performing exam
Negative result indicates Medulla or Pons damage
Oculovestibular Reflex-"Cold Caloric"
instill 20-50 ml ice water into ear canal after making sure tympanic membrane is intact
head of bead should be elevated to 30*
If rapid nystagmus-like deviation to affected ear is present the test in normal, if nothing
happens the test is negative
negative result indicates Medulla or Pons damage
intracranial pressure monitoring
o Indications: GCS score of 3-8
o purpose is to indicate responses to therapy & augment neurological assessment
o Methods
Parenchymal/subarachnoid bolt, fiberoptic scope-direct measurement of pressure, but risk of
bleeding & infection
Intraventricular catheter-CSF measures & drainage, but risk of infection & bleeding. This is most
common & most reliable, allowing for intrathecal meds to pass & CSF draining if needed
Epidural probe-no direct measure of drainage but easy to insert with lowest risk of infection
Nursing Care of IICP
o AVOID actions that increase ICP such as deep suctioning, coughing, straining, PEEP, hip flexion, pain, &
abdominal or bladder distention
o AVOID actions that impair cerebral drainage such as supine position, low head, and twisted neck
o make sure airway is patent & PaO2 is >80 mmHg
o keep noise & light to a minimum to avoid excess stimulation
o HOB at 30*
o Keep PaCO2 at 35-4 mmHg & avoid hyperventilation
Treatment of IICP
o Mannitol-osmotic diuretic that acts within 20 minutes to decrease cerebral blood flow & edema
use filter needle to draw up from vial r/t crystalization
o Oxygen-to prevent hypoxia that causes cerebral vasodilation & further increases ICP
o MAP >70
o BP management with fluids, vasoconstrictors, & antihypertensives to keep MA/CPP acceptable
o decrease metabolic demands
Induce hypothermia to a goal of 34-35*C
give Benzos to reduce agitation & restlessness
barbituates, analgesia, NMBA, & sedation as appropriate
o hyperventilation
Cerebral Blood Flow
pressures maintained by autoregulation
o MAP in range of 50-150 mmHg does not alter CBF
Factors that change CBF
o Acidosis/hypoxia r/t cerebral vasodilation
o alkalosis r/t vasoconstriction
o increased metabolic rate=increased CBF
o decreased metabolic rate=decreased CBF
Traumatic brain injury
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Aquino. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $15.49. You're not tied to anything after your purchase.