This site is 100% ad supported. Please add an exception to adblock for this site.

NR202 Test 5 Intracranial pressure ICP

Terms

undefined, object
copy deck
Define Intracranial Pressure and list the intracranial components
⬢ Definition: Pressure exerted by the combined volume of three intracranial components:
- brain tissue
- cerebrospinal fluid
- blood
What is the Monroe-Kelly hypothesis
Monroe-Kelly hypothesis: ICP remains stable as long as the volume that is added is balanced by the volume that is displaced.
- ICP = CSF volume + blood volume + volume of brain tissue
Intracranial Pressure (ICP) – what is normal =
⬢ 0-15 mm Hg
⬢ 60- 180 cm H20
- Cerebral Volume
⬢ Brain tissue = 80%
⬢ Cerebral blood volume = 10%
⬢ cerebral spinal fluid [CSF fluid= 10%
⬢ What is cerebral blood flow provided by? ______ What is the definition of this term
⬢ Cerebral blood flow provided by: Cerebral Auto-regulation:
- Maintenance of Cerebral Blood Flow by altering the diameter of the arterioles
- In response to changes in Cerebral Perfusion Pressure
⬢ What is Cerebral Perfusion Pressure (CPP):
- measurement provides: estimate of adequacy in 02 circulation
- difference between the mean systemic arterial pressure and the mean intracranial
pressure. Usually between 60-100 mm Hg
Auto-regulation is ineffective with:
ischemia
⬢hypoxia hypercapnia
brain trauma

Must have systolic BP between 60-140.
Must have ICP < 30
Hypercapnia-What is an increased and decreased CO2 level mean and what does a decreased PO2 level mean, what are these levels?
- pC02 >45 = cerebral vasodilation
- pC02 <35 = cerebral vasoconstriction
⬢ p02 < 60 = cerebral vasodilation
Cycle for brain swelling
Increased Intracranial Pressure ⬢ What is the Etiology
- Increased brain volume
-Cerebral edema intracranial mass
- Increased cerebral blood flow-Oxygenation in the brain
⬢ intracranial bleed, cerebral aneurysm, elevated pC02, hypoxia - Increased cerebrospinal fluid
⬢ hydrocephalus, meningitis, tumors that obstruct CSF flow
Brain tumor/hemorrhage
Conditions Increasing ICP
⬢ Sneezing
⬢ Vomiting
⬢ Coughing
⬢ Suctioning (frequent)
⬢ Valsava
⬢ Increased activity
⬢ Increased PaC02
⬢ Hyperthermia
⬢ Seizures
⬢ Neck flexion
⬢ Emotional upset
⬢ Decreased PaO2
Complications of ICP
⬢ Brain herniation
⬢ Diabetes insipidus (deficiency of ADH secretion causing increased u/o and dehydration)
⬢ Syndrome of Inappropriate Antidiuretic Hormone secretion (SIADH) - increased ADH secretion causing decreased u/o and fluid overload.
⬢ Seizures
Symptoms of increased ICP
⬢ Stage I
⬢ Stage I
- altered vision (blurred, double)
- confusion (first to time, forgetful)
- drowsiness (lethargy, more stimulation needed, restless, irritable)
- breathing changes (depends on LOC-cheyne stokes)
- slight ipsilateraly pupillary changes (sluggish/ovoid)
- ptosis-drooping of eyelids
- early am HA/projectile vomiting
- motor--pronator drift, subtle weakness to hemiplegia on contralateral side
⬢ Middle to late stages (cushings)
Symptoms of increased ICP Stage 2
Stage 3
⬢ Stage 2
- Systemic arterial vasoconstriction
⬢ attempt to overcome ICP

⬢ Stage 3
- decreased arousal
- Cheyne Stokes to apneustic
- Hyperventilation
- widened pulse pressure
- bradycardia

⬢ Cushings signs: widened pulse pressure, decreased pulse, decreased respirations. - Stage 2-3
- body's last attempt to compensate
Symptoms of increased ICP
⬢ Stage 4 (decompensation)
Symptoms of increased ICP
⬢ Stage 4 (decompensation)
- Herniation
⬢ unarousable
⬢ tachycardic, hypotension, narrowed pulse pressure
⬢ tissue hypoxia and brain death
⬢ posturing from decorticate to decerebrate
⬢ pupils from small & reactive or sluggish to fixed and dilated
⬢ Absence of dolls eyes [negative] negative respirations
Compensatory Mechanisms for Increased ICP
- shunting of CSF into spinal subarachnoid space
- increased CSF absorption
- Decreased CSF production
- shunting of venous blood out of skull
Decompensation
- Decompensation: herniation (displacement of brain tissue to another area of the
brain or outside cranial vault)
- blood supply to medulla is cut off
- pupils fixed and dilated
- from decorticate to decerebrate posture
⬢ irreversible brain damage
Herniation
Diagnostics of ICP:
⬢ CT or MRI to determine possible causes of ICP
- CT: detailed outlines of bone, tissue & fluid structures; reflect shift of structures and acute hemorrhage
- MRI: graphic image of bone, fluid & soft-tissue structures with more defined image of anatomical details;
Normal CT Scan
⬢ Intracerebral Edema & Hemorrhages MRI
⬢ CBF monitoring (blood flow)
- Transcranial Doppler ultrasonography o aimed through cranial "windows"
- Radioisotope brain scan
⬢ Damaged areas absorb more of the isotope
EEG Tracings
⬢ A: normal
⬢ B: Generalized slowing
⬢ C: Temporal spikes (seizures)
⬢ D: Electrocerebral silence
Interventions for ICP
⬢ Hypothermia: decreases 02 consumption, but may decrease CBF unless induced barbiturate coma
⬢ Craniotomy (bone flap) remove some bone of skull-more room for the brain
⬢ Hemodynamic monitoring:
- MAP between 115-120, less than 140 fluid up
- PAWP 14-16
ICP monitoring

Normal 0-15
- Keep less than 30
⬢ Ventriculostomy, shunt: drainage of CSF
- against positive pressure to prevent collapse
- sterile technique
ICP Measurement Techniques
⬢ Intraventricular
- Ventriculostomy catheter placed through burr hole into lateral ventricle
- Connected to pressure tubing & transducer
⬢ Intraparenchymal catheter
- Fiberoptic transducer tipped catheter placed directly into brain tissue
- Used in patients with displaced or compressed ventricles
⬢ Subaraclmoid Technique
- Subaraclmoid screw extended into the subdural or subaraclmoid space
⬢ Epidural Sensor
- Placement of epidural device between skull & dura
Medications
- Corticosteroids
- Corticosteroids (dexamethasone or Decadron) reduces ICP through unknown mechanism. Side effects: GI ulcers and bleeding, and elevated blood glucose .
⬢ Research: Ineffective with severe head-injury, but reduces vasogenic edema associated with brain tumors, abscesses, & spinal cord tumors
Medications-Calcium Channel Blockers
Calcium Channel Blockers (nimodipine, nicardipine) prevent cerebral vasospasm, however cerebral vasodilation increases ICP-contraindicated with space-occupying lesions or cerebral edema.
Medications-Sodium Nitroprusside
Sodium Nitroprusside: used with severe intracranial hypertension; should maintain MAP of at least 130.
Medications-Barbituates:
: phenoobarbital: may be used to induce coma (decreases metabolic & 02 demands)
⬢ also:
- suppresses seizure activity,
- reduces restlessness & irritability
⬢ research: increased survival
Medications-Beta Blockers
Beta Blockers: Labetalol (Trandate) decreases ICH, improves CPP, without increased ICP. Contraindicated in patients with space occupying lesions or cerebral edema
Medications: Sedatives:
Sedatives: phenobarbital, propofol, versed, ativan."Lorazepam⬝
⬢ Baseline evaluation of mental & neurological status
⬢ Periodic discontinuation
- Analgesics: Fentanyl or MS frequently used;
⬢ patients in pain become combative, restless & agitated
- Antipyretics: Acetaminophen is used to control fever.
Medications:
stool softeners: - Anticonvulsants: (dilantin, tegretol, valium)
- Histamine H2 blockers
stool softeners: colace
- Anticonvulsants: (dilantin, tegretol, valium) used to manage seizure activity
- Histamine H2 blockers (pepcid, tagamet, zantac) prevent GI irritation & bleed
Neuromuscular Blockades (Vecuronium)
- Neuromuscular Blockades (Vecuronium)
⬢ used to counteract increases in ICP associated with reflex motor responses to suctioning and mechanical ventilation
⬢ trane of four
- four stimuli delivered at intervals of 0.5 sec.
- Ulner at wrist
- thumb should twitch 2-3 times
⬢ must sedate & treat for pain ⬢ must be on ventilator
The doctor has just ordered IV albumin and IV lasix for the patient with cerebral edema. Which medication should be given first?
Albumin
Nursing Interventions
⬢ Goals: reduce ICP, improve CPP, reduce brain shift
-IV fluids (Avoid hypoosmolar solutions D5W-goes more into cells)
- Neuro assessment every 1-2 h
- If on ventilator, minimal suctioning,
- hyperventilate as ordered (keep pC02 above 30)
- Elevate HOB 30-45 degrees, head midline
- Avoid knee flexion
- Assess bowel and bladder function
- Do not cluster activities
- Quiet, calm environment
- Avoid Valsalva maneuver (coughing, sneezing)
- If administering tube feedings, give at room temperature
- If ICP monitor, monitor for infection, change dressing 24-48 hours, monitor for
leaking CSF (clear fluid which tests glucose +) -no nose blowing
- Monitor I & 0, possible fluid restriction
Care of the Client with a Craniotomy
⬢ Craniotomy: surgical procedure performed to gain access to the intracranial contents and accommodate brain swelling
⬢ Indications
- Intracranial neoplasms
- Head injuries (hematoma, cerebral edema or depressed skull fracture)
Space occupying lesions (bleeds, abscess, aneurysms, arteriovenous
malformations)
Preoperative nursing care
⬢ Permit signed
⬢ Hair cut and shaved
⬢ surgical scrub/ shampoo
⬢ report breaks in skin of scalp
⬢ record baseline neuroassessment
⬢ foley or NG if ordered (may be done after anesthesia)
⬢ explain post-op environment (monitoring equipment, ventilator, communication)
Post-op Nursing Care
- Prevent injury & infection
⬢ Care same as pt with increased ICP
⬢ Assess wound, eyes, ears, nose for CSF leaks and/or infection
⬢ Provide protective eye care
⬢ NPO until fully conscious (and extubated)
⬢ Do not lower head in Trendelenburg or place in supine position
⬢ Avoid placing on operative side if large tumor or bone removed
⬢ Maintain mobility of joints and extremities - assess motor/sensory responses
- PROM q 12 h
⬢ Improve body image
Encourage use of wigs, turbans, and scarves when dressings removed
- encourage use of normal cosmetics
- promote self-care
Post-op Nursing Care
speech
⬢ Improve speech
- provide audiovisual aids as needed
- speak in simple, slow instructions
- refer to speech therapist
Cerebral Aneurysm
⬢ History
⬢ History
- adults 35-60 y.o., female
- atherosclerosis
- congenital defect
- head trauma
- hypertension
- familial
- cigarette smoking, use of cocaine
- use of OTC med (nasal sprays or antihistamines)
Cerebral Aneurysm Pathophysiology
⬢ Most located at bifurcations in or near Circle of Willis
⬢ Act as space occupying lesions
⬢ Saccular and Berry
⬢ Rupture due to thin walls
- Most common first indication is acute subarachnoid hemorrhage (Bleed), or intracerebral
hemorrhage
Cerebral Aneurysm
- Manifestations
⬢ many have no manifestations and no problems
⬢ headaches
⬢ occasional ptosis and dilated pupil and diplopia or blurred vision
⬢ pain above and behind the eye
⬢ nausea and vomiting
⬢ stiff neck
⬢ dysrythmias and vasospasm
⬢ hemiplegia/hemiparesis
⬢ other signs of ICP
⬢ Warning signs (50% of patients) - headaches
-lethargy
- neck pain
- "noise in the head"
- optic, or oculomotor dysfunction
Cerebral Aneurysm
Diagnostic tests
Surgery
⬢ Diagnostic tests
⬢ CT Scan
- Cerebral arteriography
Surgery is treatment of choice Clipping or coiling
Presurgical Nursing Interventions
- Interventions to treat or prevent ICP
- Sedation
- Quiet environment
- Prevention of coughing, & constipation
- hot or cold beverages may be prohibited
- limit visitors
Post-surgical nursing interventions
⬢ Baseline neuro assessment
⬢ Monitor changes in neuro status
⬢ possible mechanical hyperventilation
⬢ I and O
⬢ vital signs (esp. BP)
⬢ monitor for dysrythmias
⬢ talk directly to the patient
⬢ monitor sodium
⬢ monitor for vasospasm
- causes decreased CBF, depriving brain tissue of oxygen
- treat with triple H therapy & nimodipine
⬢ hypervolemia
⬢ induced hypertension
⬢ hemodilution
⬢ close monitoring of hemodynamic parameters
⬢ monitor for pulmonary edema
Craniocerebral Trauma
⬢ Types of Injuries
-Acceleration Injury: head struck by a moving object
- Deceleration Injury: head hits a stationary object
- Acceleration-Deceleration Injury (coup-contrecoup phenomenon): head hits object
and the brain "rebounds"
- Deformation Injury Skull Fractures
Craniocerebral Trauma
⬢ Linear
⬢ Depressed:
Linear: simple clean break
- Most common
- force over wide area of skull
⬢ Depressed: - bone fragments may penetrate into the brain tissue
Craniocerebral Trauma
⬢ Basilar:
⬢ Basilar: floor of skull
- serious
- contact between CSF and sinuses
- CSF may leak through sinus
- allow bacteria to contaminate CSF
- Raccoon Eyes
_ Battle Sign Behind ear on mastoid bone
Craniocerebral Trauma

⬢ Concussion
- Description: Transient, temporary neuro dysfunction (least serious)
Usually loss of consciousness from seconds to hours
⬢ retrograde amnesia, HA, drowsiness, visual disturbances
⬢ postconcussive syndrome: HA, inability to concentrate, memory problems, dizziness, irritability
- Mechanism of Injury: Acceleration-Deceleration
- Prognosis: Most benign form of brain injury
Craniocerebral Trauma
⬢ Contusion
⬢ Hemorrhage diffused
cerebral edema & hemorrhage peak in ___-____ hrs
larger areas may expand over ___-____ days
⬢ Contusion
- Description: Bruise on the surface of the brain
⬢ Hemorrhage diffused
- Mechanism of Injury: Brain strikes inner skull (coup & contrecoup)
- Prognosis: Varies depending on location & degree
⬢ cerebral edema & hemorrhage peak in 12-24 h
⬢ larger areas may expand over 2-3 days
Craniocerebral Trauma- Manifestations:
⬢ loss of consciousness
⬢ behavior changes
⬢ ICP
⬢ hemiparesis
⬢ abnormal posturing
⬢ bradycardia
⬢ seizure
⬢ respiratory arrest
⬢ Hypotension
Intracranial Hematoma
Subdural Hematoma venous bleed
location and etiology
⬢ Subdural Hematoma venous bleed
- Location: bleeding or clot between dura and brain
- Etiology: trauma, coagulopathies, aneurysm rupture. More frequently a venous
bleed
Intracranial Hematoma
Subdural Hematoma venous bleed
Prognosis:
- Prognosis:
⬢ Acute: sx in 24-48 h. needs immediate intervention
⬢ Subacute: sx in 48hr- 2 wk
⬢ Chronic: minor head injury in elderly. Sx in weeks to months
⬢ -May mimic dementia
Intracranial Hematoma
Subdural Hematoma venous bleed
- Manifestations
- treatment
- Manifestations
⬢ Acute: change in LOC, pupillary signs, hemiparesis, increasing BP, decreasing HR, slowing RR
- treatment: burr holes, and insertion of drainage catheters
⬢ Epidural Hematoma Arterial Bleed

Location
Etiology
Prognosis
⬢ ⬢ Epidural Hematoma Arterial Bleed
- Location: bleeding or clot between skull and dura
- Etiology: head injury, often from arterial bleed
⬢ linear fx across temporal bone lacerating middle meningeal artery
- Prognosis: considered an extreme emergency; marked neurologic deficit or resp arrest may occur within minutes.
- Death from herniation not bleeding
⬢ ⬢ Epidural Hematoma Arterial Bleed
- Manifestations:
- Manifestations:
⬢ "talk & die syndrome" period of lucidity, then rapid deterioration & death
⬢ deterioration of consciousness,
⬢ ipsilateral dilation and fixation of a pupil
⬢ Contralateral paralysis of an extremity
⬢ Intracerebral Hematoma
-Description
- Etiology
- Prognosis
- Manifestations
Description: a collection of 25 mL or more of blood within the brain tissue
- Etiology: MV A most common cause
- Prognosis: surgical intervention only if continued expansion
- Manifestations: insideous onset, HA, development of focal neuro deficits
⬢ Intracerebral Hematoma
- Complications
- Complications
⬢ increased ICP
⬢ Pulmonary edema: neurogenic cause
⬢ Seizures: keep sx equipment close, padded rails, IV diazepam (# 1 protect patient)
CFS leak clear, watery drainage.
Test with blood glucose strips
- Do not clean, irrigate or suction areas of drainage
- Instruct patient not to blow nose, sniff or put finger in nose or ear.

Deck Info

51

permalink