cueFlash

Glossary of NR202 Test 5 Intracranial pressure ICP

Start Studying! Add Cards ↓

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.

Add Cards

You must Login or Register to add cards