The rigid cranial vault contains:
Brain Tissue (1400g/80%)
Cerebrospinal fluid (75ml/10%)
The volume and pressure of these three components are
usually in the state of equilibrium and produce the ICP.
ICP is usually measured in the lateral ventricles, with
normal pressure being 10-20mmHg.
CSF is produced by the Choroid Plexuses, specialized
structures made of ependymal cells which are located in
CSF fills the brain ventricles, the central canal of the spinal
cord and the subarachnoid space.
CSF bathes the brain and spinal cord , providing a
protective cushion around the CNS.
CSF should be clear and transparent in appearance.
1. CSF IS PRODUCED BY THE CHOROID PLEXUS IN EACH
OF THE FOUR VENTRICLES.
2. CSF FROM THE LATERAL VENTRICLES FLOWS TO THE
3. CSF FLOWS FROM THE THIRD VENTRICLE THROUGH
THE CEREBRAL AQUEDUCT TO THE FOURTH
4. CSF EXITS THE FOURTH VENTRICLE THROUGH OPENING
IN THE WALL OF THE FOURTH VENTRICLES AND ENTERS
THE SUBARACHNOID SPACE. SOME ENTERS THE CENTRAL
CANAL OF THE SPINAL CORD.
5. CSF FLOWS THROUGH THE SUBARACHNOID SPACE TO
THE ARACHNOID GRANULATION IN THE SUPERIOR
SAGITAL SINUS, WHERE IT ENTERS THE VENOUS
States that, because of the limited space for
expansion within the skull, an increase in any one
components causes a change in the volume of the
Because the brain tissue has limited space to expand, compensation
typically is accomplished by displacing or shifting CSF, increasing the
absorption or diminishing the production, or decreasing the cerebral
blood volume. Without such changes, ICP will begin to rise. Under
normal circumstances, minor changes in blood volume and CSF volume
occur constantly due to alterations in intrathoracic pressure, posture, bp
and systemic O2 and CO2 levels.
Ischemia in early stages stimulates vasomotor center
causing systemic pressure to rise to maintain cerebral
Blood pressure, pulse and respirations are suggestive of
increase in ICP.
Increase in PaCO2 in blood and brain tissue causes
cerebral vasodilation leading to inrease CBF AND ICP.
Decrease in PaCO2 has a vasoconstrictive effect, limiting
blood flow to the brain.
Decreased venous flow may also increase Cerebral blood
volume, thus incresing in ICP
Abnormal accumulation of fluid in intracellular,
extracellular or interstitial space or both. As
braintissue swells within the rigid skull several
mechanisms attempt to compensate for Increase in
ICP, it includes:
Autoregulation-brains ability to change the diameter
of its blood vessels automatically to maintain a
constant CBF during alterations in Systemic Blood
Arterial Systemic Blood Pressure is 50-150mmHg.
ICP changes are closely linked with Cerebral
Perfusion Pressure and ICP is less than
40mmhg.Normal CPP is 70-100mmHg.
Patients with less than 50 mmHg CPP experience
irreversible neurologic damage therefore CPP must
be maintained at 70-80mmHg to ensure adequate
CBF decreases significantly causing a Cushing
Is present when Ischemic, the vasomotor center
triggers an increase in arterial pressure in an effort
to overcome Increase in ICP. A Sympathetically
mediated response cause an increase in the systolic
blood pressure with the widening of the pulse
pressure and cardiac slowing.
Increase in Systolic Blood Pressure, widening of
pulse pressure and reflex slowing of the heart rate.
Secondary effect in Brain Tumors,
Subarachnoid Hemorrhage and toxic and
Increase in Intracranial Pressure
Decrease Cerebral Perfusion
A-ltered respiration (cheyne
L-evel of consciousness
Cerebral ischemia and cell death
Stimulates further swelling
Restlessness without apparent cause
Confusion or increasing drowsiness
May shift brain tissue
through openings in the
rigid dura or presses
down on the brain stem
Cessation of blood flow to the
brain leading to irreversible
brain anoxia and brain death
Neurologic functioning deteriorates
Classification: Diagnostic agent, Osmotic
diuretics, Urinary irrigant
Indication: reduction of intracranial pressure and
treatment of cerebral edema.
Contraindication: contraindicated with anuria
due to severe renal disease.
Precautions: use cautiously with pulmonary
congestion, active intracranial bleeding (except
during craniotomy), dehydration, renal disease,
heart failure, pregnancy, lactation.
Availability: given in bolus doses
Side Effects: increased urination, GI upset, dry
mouth, headache, blurred vision.
Assess patient’s history of pulmonary congestion,
active intracranial bleeding, dehydration, renal
disease, heart failure, pregnancy, lactation.
Assess skin color, lesions, edema, hydration,
orientation, muscle strength, reflexes, pupils,
pulses, BP, perfusion, RR patterns, adventitious
sounds, urinary output patterns, S. electrolytes,
urinalysis, renal function test.
Do not expose solutions to low temperatures,
crystallization may occur.
Monitor serum electrolytes periodically with
Inform patient that he/she may experience side
Encourage to report difficulty breathing and chest
Classification: antiarrhythmic, group 1b;
Indication: prevention of siezures.
Contraindication: hypersensitivity to
hydantoins, sinus bradycardia, sinoatrial block,
strokes-adams syndrome, pregnancy, lactation.
Precautions: use cautiously with acute
intermittent porphyria, hypotension, severe
myocardial insufficiency, DM, hyperglycemia.
Side effects: drowsiness, dizziness, confusion,
blurred vision, GI upset.
Monitor injection sites carefully, drug solutions are
very alkaline and irritating.
Give oral drug with or without food in consistent
Monitor hepatic function periodically during longterm therapy; monitor bld. Counts and urinalysis
Monitor bld. urine sugar of patients with DM
Monitor bld. proteins to detect early malfunction of
the immune system.
Inform client that he/she may experience side
Encourage to report rash, severe nausea and
vomiting, drowsiness, slurred speech, impaired
coordination (ataxia), swollen glands, bleeding,
swollen and tender gums, yellowish discoloration
of the skin and eyes, joint pain, unexplained fever,
sore throat, persistent headache, malaise.
Classification: antiepileptic; barbiturate;
hypnotic; sedative or hypnotic
Contraindication: contraindicated with
hypersensitivity to barbiturates, manifest or latent
porphyria, marked liver impairment, nephritis,
severe respiratory distress, previous addiction to
sedative-hypnotic drugs, pregnancy.
Precautions: use cautiously with acute or chronic
pain, seizure disorders, fever, hyperthyroidism,
DM, severe anemia, pulmonary or cardiac disease,
status asthmaticus, shock, uremia.
Availability: injection 50mg/mL
Side Effects: drowsiness and anxiety
Do not administer intra-arterially; may produce
arteriospasm, thrombosis, or gangrene.
Administer IV doses slowly.
Administer IM doses deep in a muscle mass.
Do not use parenteral form if solution is discolored
or contains precipitate.
Monitor injection sites carefully for irritation, and
extravasation (IV use); solutions are alkaline and
very irritating to the tissues.
Monitor BP, Pulse, and respiration carefully during
Inform client that he/she may feel drowsy and less
Instruct client not to try to get up after receiving
Other Drugs that may be used:
NEUROMUSCULAR BLOCKING AGENTS
INEFFECTIVE CEREBRAL TISSUE
PERFUSION RELATED TO INCREASED ICP
GOAL: Within 8 hours of nursing interventions
patient will have stable or improving levels of
Note customary baseline data (e.g., usual BP, weight,
mentation, ABGs, and other appropriate study
provide comparison with current findings.
Determine presence of visual, sensory/motor
changes, headache, dizziness, altered mental
status, personality changes.
this may indicate presence increased intracranial
Note history of brief/intermittent periods of
This suggests transient ischemic attacks-TIAs
Elevate head of the bed 30 degrees and maintain
head/neck in midline or neutral position.
To promote circulation/venous drainage.
Assist with/monitor hypothermia therapy.
Which may be used to decrease metabolic and
Encourage client to quit smoking (if he/she does),
join smoke-out, and other stop-smoking program.
Smoking causes vasoconstriction and may further
Avoid emotional stress, frequent arousal from sleep, and
environmental stimuli (noise, conversation).
This may increase ICP.
Administer medications such as diuretics
(mannitol), anticonvulsant (phenytoin) as ordered.
These drugs are used to decrease cerebral edema
and prevent seizure.
Ineffective airway clearance related to
GOAL: Within 30 minutes of nursing intervention
interventions client will demonstrate
absence/reduction of congestion, improved oxygen
Position head midline with flexion appropriate for
To open or maintain open airway in at-rest or
Elevate the head of the bed.
may aid in clearing secretions as well as improving
venous drainage of the brain.
Auscultate breath sounds and assess air
To ascertain status and note progress.
because it increases ICP.
Suction with care the secretions obstructing the airway
because transient elevations of ICP occur with suctioning.
Provide opportunities for rest; limit to level of
Maintain a neurologic observation record.
Repeated assessments of the patient are made frequently
to immediately note improvement or deterioration.
C E R E B R A L A N G I O G R A P H Y
C O M P U T E D T O M O G R A P H Y ( C T )
M A G N E T I C R E S O N A N C E I M A G I N G
P O S I T R O N E M I S S I O N T O M O G R A P H Y
T R A N S C R A N I A L D O P P L E R
L U M B A R P U N C T U R E
Cerebral angiography is a procedure that uses a special dye (contrast material) and
x-rays to see how blood flows through the brain.
A computed tomography (CT) scan is an imaging method that uses x-rays
to create pictures of cross-sections of the body.
Magnetic Resonance Imaging is a test that uses a magnetic field and pulses of
radio wave energy to make pictures of organs and structures inside the body.
Positron emission tomography (PET)
Is a test that uses a special type of camera and a tracer (radioactive
chemical) to look at organs in the body. The tracer usually is a
special form of a substance (such as glucose) that collects in cells
that are using a lot of energy, such as cancer cells.
During the test, the tracer liquid is put into a vein (intravenous,
or IV) in your arm. The tracer moves through your body, where
much of it collects in the specific organ or tissue. The tracer gives off
tiny positively charged particles (positrons). The camera records the
positrons and turns the recording into pictures on a computer.
PET scan pictures do not show as much detail as computed
tomography (CT) scans or magnetic resonance imaging
(MRI) because the pictures show only the location of the tracer. The
PET picture may be matched with those from a CT scan to get more
detailed information about where the tracer is located.
A PET scan is often used to evaluate cancer, check blood flow, or see
how organs are working.
Transcranial Doppler is a test used to measures the velocity of blood flow
through the brains blood vessels
Is a diagnostic and at times therapeutic procedure
that is performed to collect a sample of cerebrospinal
fluid for biochemical, microbiological and cytological
Shows that you have high pressure in the
cerebrospinal fulid that sorrounds your brain and
Rarely as a treatment (therapeutic lumbar puncture)
to relieve increased intracranial pressure.
Shunt Surgery -where a catheter (a thin, flexible tube) is inserted into
the fluid-filled sapace in your brain or spine to divert excess fluid to
another part of the body.
Lumboperitoneal shunting - Shunting fluid from the spine to the
Ventriculoperitoneal shunting- from the brain to the abdomen
Ventriculoatrial shunting- from the brain to the heart