altered cerebral function and increased intracranial pressure (icp) ashley valentino msn, bsn, rn...
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Altered Cerebral Function and Increased intracranial pressure (ICP)
Ashley Valentino MSN, BSN, RNupdated Spring 2013
From the notes of Charlene Morris MSN, RN
John Nation MSN, RN
&
Marnie Quick MSN, RN, CNRN
Head Injury Head Injury
Head injury – a broad classification that includes any injury or trauma to _____, ______, or _______.
TBI is a serious form of head injury– 5.3 million live with disabilities resulting from TBI – MVC, falls most common cause– Other causes? – Males twice likely to sustain TBI than females– Head trauma= high potential for poor outcome**
Deaths from trauma occur at what points?
**Factors that predict poor outcome = ICP levels > than 20 mmHg, presence of intracranial hematoma, abnormal motor responses, GCS on arrival**
A score of 13 to 14 indicates mild deficit. A score between 9 and 12 points to moderate deficit, and a score of 8 or less indicates severe coma.
Glasgow Coma ScaleGlasgow Coma Scale
Head Injury: TBIHead Injury: TBI
GCS on arrival strong predictor of survival!! GCS below ____ indicates only 30%-70% chance of survival Majority of deaths occur immediately after injury
- massive hemorrhage
- shock
** Monitor neurological status; prompt surgical intervention critical in prevention of death**
Head Injury: Scalp Head Injury: Scalp LacerationsLacerations
External head trauma Associated with profuse bleeding
Major complications:- Bleeding- Infection
Head Injury: Skull FracturesHead Injury: Skull Fractures
Frequently occur with head trauma Major complications = intracranial infections, hematoma, brain tissue damage Characteristics:
- linear vs. depressed- simple, comminuted, compound- open vs. closed
Severity of skull fracture depends on? TX – possible craniotomy if loose bone fragments
craniectomy if large amounts of bone destroyed
Head Injuries: ManifestationsHead Injuries: Manifestations
Depends on location of fracture (Box 57-7)
Symptoms can evolve over course of several hours - Battle’s sign- what is this?
- Rhinorrhea – patient teaching?
- Otorrhea If these occur, raise HOB & notify physician immediately!!
** Risk of _________ is high with a CSF leak **
- what will be administered?
- Dextrostix, Tes-tape, halo
- NG tube??
Head Trauma: ConcussionHead Trauma: Concussion
Minor diffuse injury GCS 13-15 change in LOC may or may not lose total conciousness Postconcussion syndrome
- 2 wks – 2 months after injury
- What s/s will you see?
- What will we teach?
Diffuse Axonal Injury (DAI) Diffuse Axonal Injury (DAI)
Results after mild, moderate, or severe TBI Damage to cerebral hemispheres, basal ganglia, thalamus, and brainstem axon swelling and disconnection 12-24 hours to develop Symptoms:
- decreased LOC
- increased ICP, global cerebral edema
- what else will you see?
*90% patients with DAI remain in vegetative state*
Focal Injury: Laceration Focal Injury: Laceration
actual tearing of brain tissue Can occur with depressed or open fractures with penetrating injuries ** Tissue damage severe ** surgical intervention impossible Medical management – like what? Intracerebral hemorrhage associated with cerebral laceration – poor prognosis!
- Leads to increased ICP, expansion of hematoma
Focal Injury: ContusionFocal Injury: Contusion
bruising of brain tissue; localized minor to severe- GCS scale?
most associated with closed head injury may contain areas of
- hemorrhage, infarction, necrosis, and edema
occurs at fracture site seizures common complication Coup- countercoup injury (often noted)
- brain moves inside skull- related to high impact injury - multiple contused areas
Focal Injury: Contusion Focal Injury: Contusion
Prognosis depends on what? May continue to rebleed appear to “blossom” on CT scan
- * worse neurological outcome ** seizures common complication anticoagulant use associated with ________,
__________, and ___________.
What should we assess for?
Focal Injury: Epidural Focal Injury: Epidural Hematoma Hematoma
results from bleeding between the _____ and inner surface of the skull ** Neurological emergency!! **
rapid surgical intervention what S/S will you see?
associated with linear fracture crosses major artery in dura causes tear can be venous or arterial in origin Venous tear = develop slowly arterial tear = rapidly developing, high pressure
- often includes meningeal artery
Focal Injury: Subdural Focal Injury: Subdural Hematoma Hematoma
occurs from bleeding between the ______ and the
_______ _____ of the ________. usually results from injury to brain tissue and blood vessels more common in older adults – why? can be confused with dementia usually venous in origin – develops?
sagittal sinus = source of most subdural hematomas can be acute, subacute, and chronic
Focal Injury: Subdural Focal Injury: Subdural Hematoma Hematoma
Acute subdural hematoma 24 – 48 hours after trauma immediate deterioration – what will we see? treatment?
Subacute subdural hematoma 48 hr – 2 wk after trauma alteration in mental status as hematoma develops treatment?
Chronic subdural hematoma > 20 days after injury progressive alteration in LOC TX = evacuation, membranectomy
Focal Injury: Inracerebral Focal Injury: Inracerebral Hematoma Hematoma
occurs from bleeding within brain tissue usually in frontal and temporal lobes – why? occurs in 16% of head injuries
the _______ and ______ of hematoma determines patients outcome
Diagnostic Tests Diagnostic Tests
______ is best diagnostic tool to evaluate for head trauma Other studies:
MRI PET Transcranial Doppler – assess what?
Cervical Spine Xray
TreatmentsTreatments
** Prevent secondary injury = manage elevated ICP; treat cerebral edema ** timely diagnosis, surgery if necessary! ** significant neurological impairment = surgical evacuation! **
Burr holes – used in extreme emergency followed by craniotomy drain placed – to prevent what? If extreme swelling expected = hemicraniectomy – why?
Burr HolesBurr Holes
Planning: Overall GoalsPlanning: Overall Goals
maintain adequate cerebral oxygenation & perfusion remain normothermic achieve pain control, reduce anxiety free of infection attain maximal motor, cognitive, and sensory function
Nursing Interventions Nursing Interventions
Health promotion – like what?
** Monitor for changes in neurological status ** maintain cerebral perfusion and oxygenation hemodynamic monitoring be aware of coexisting injuries or conditions
Frequent Neuro checks calm approach, reduce anxiety maintain temp of 36 to 37 degrees C – cooling blanket? sedation as necessary – prevent what? administer antiemetics for nausea/vomiting – why?
Nursing Interventions Nursing Interventions
Provide patient/family support – spiritual care? surgery consent provide frequent status updates, open visitation
Home care prevention of seizures drug of choice? assess nutritional status speech therapy, OT, PT assistance with financial aid, child care, social work no driving, no drinking, no use of firearms assist with role change (spouse to caregiver)
Brain TumorsBrain Tumors
Can occur in brain or spinal cord rarely metastasize outside CNS
contained by meninges
White males have highest incidence of malignant brain tumors Primary vs. secondary Secondary most common type
primary = arising from tissues within the brain gliomas (glioblastoma, astrocytoma)
secondary = resulting from metastasis
Brain Tumors: Manifestations Brain Tumors: Manifestations
Depend on _______ and ______ of tumor. Headaches (common)
worse at night, may awake from sleep dull, constant; throbbing
Seizures common in gliomas
Nausea, vomiting – caused by what?
memory problems, personality changes muscle weakness, sensory loss, aphasia Hydrocephalus – leads to what?
**brain tumor left untreated = increased ICP, death**
Brain Tumors: Diagnostic Brain Tumors: Diagnostic Studies Studies
Extensive history; comprehensive Neuro exam New onset of seizures? MRI, PET -detection of what?
CT = location of lesion EEG Why not lumbar puncture?? Angiography – looks at what?
Computer guided stereotacitc biopsy – preliminary
Brain Tumors: Treatment Brain Tumors: Treatment
GoalsGoals: identify tumor type, location remove or decrease tumor mass prevent/manage ICP
Surgical therapy Surgical therapy surgical removal = preferred treatment partial vs. complete removal reduces tumor mass, reducing ICP
Ventricular Shunt – Ventricular Shunt – risks?
tx for hydrocephalus; gradually put patient in upright position catheter placed in lateral ventricle; tunneled through skin drains CSF – drains into where?
Brain Tumors: Treatment Brain Tumors: Treatment
Radiation Therapy follow-up measure after surgery stereotactic radiosurgery – radiation precisely directed at a location in brain radiation seeds- may be implanted into brain complications??
tx with Decardon, Solu-Medrol - how do these work?
Chemotherapy nitrosoureas Gliadel wafer – implanted at time of surgery Ommaya reservoir Temodar – 1st oral chemotherapeutic agent
Brain Tumors: Nursing Brain Tumors: Nursing Intervention Intervention
Goals: maintain normal ICP maximize neurological functioning achieve pain control patient/family aware of prognosis, long term implications
Provide support – end of life, palliative care?
Protect patient from self harm – how?
Prevent seizures/ seizure precautions Encourage self care; mobility with supervision Establish communication system Assess nutritional status – dietary consult? TF?
Cranial Surgery: Types Cranial Surgery: Types
CraniotomyCraniotomy removal of bone flap; opening into dura to remove lesion can be used to drain blood; relieve ICP may have drain after surgery, bone flap wired or sutured
Stereotactic Radiosurgery Stereotactic Radiosurgery often computer guided precise location of specific area used for biopsy, removal of small brain tumors, drainage of hematomas * What is the advantage here? *
Post- Craniotomy Post- Craniotomy
Cranial Surgery: Nursing Cranial Surgery: Nursing Interventions Interventions
Goals: Goals: return to normal consciousness pain control, nausea maximize neuromuscular functioning rehabilitated to maximum ability
Acute Intervention Acute Intervention pre-operative teaching; provide support post-operative teaching- what to expect
** ** Primary nursing goal post-op? ** frequent neuro assessments x first 48 hours monitor fluid & electrolytes – which one? control pain and nausea – Phenergan?
Cranial Surgery: Nursing Cranial Surgery: Nursing Interventions Interventions
Acute Intervention ContinuedAcute Intervention Continued keep HOB 30-45 degrees – expect when? assess dressing: drainage, color, odor? * Notify surgeon immediately for increase in bleeding or if clear drainage is present!!! ** If bone flap removed, do not place patient on operative side! skin, mouth care scalp care, assess for infection of incision
antiseptic soap or hospital policy
Cranial Surgery: Discharge Cranial Surgery: Discharge
Encourage independence, maximize functioning rehabilitation referral – case management ST, OT, PT – will they need these at discharge? Assess nutritional status Patient/family support
Intro to Intracranial Pressure:Intro to Intracranial Pressure:
Skull is a closed box; 3 essential volume componentsSkull is a closed box; 3 essential volume components– brain tissue – 78%– blood – 12%– cerebrospinal fluid (CSF) – 10%
What is Intracranial Pressure (ICP) What is Intracranial Pressure (ICP) ? ? – hydrostatic force measured in brain CSF compartment– a balance among 3 essential components maintains ICP
What factors influence ICP?What factors influence ICP?
Changes inChanges in: – arterial pressure– venous pressure – intrabdominal or intrathoracic pressure– posture– temperature– blood gases – specifically which one?
* An increase or decrease in ICP depends on the ability of the brain to accommodate to changes *
Monro-Kellie doctrine: Monro-Kellie doctrine:
Alexander Monro & George Kellie (18th century) * Only applies to closed skull* “ The three components must remain relatively constant
within the closed skull structure”
“ If the volume of any 3 components increases, volume from another component will decrease; the total intracranial volume will not change”
– compensatory adaptations? – What if compensatory adaptations fail?
How is ICP measured? How is ICP measured?
Measured in ventricles, subarachnoid space, subdural space, or brain tissue – using what?
** Normal ICP = 5 – 15 mmHg **
A sustained pressure above the upper limit is considered abnormal
ICP Pressure Transducer ICP Pressure Transducer
Cerebral Blood Flow: Cerebral Blood Flow:
Cerebral blood flow (CBF) = amount of blood in ml passing through 100 g of brain tissue in __________
universal CBF = 50ml/min per 100g brain tissue
** Difference in blood flow between white matter and gray matter of the brain **
• gray matter faster blood flow (75ml/min) • white matter slower blood flow (25ml/min)
Maintenance CBF critical – what does the brain need?
How is CBF Regulated? How is CBF Regulated?
Brain regulates own CBF in response to metabolic needs ____________ is the automatic adjustment in size of
cerebral blood vessels to maintain constant blood flow – What is the purpose?
**Only effective in a person with MAP of 50mmHG – 150 mmHg ** < 50 mmHg = CBF decreases; cerebral ischemia
What symptoms would you see? > 150 mmHg = vessels maximally constricted
Regulating CBFRegulating CBF
___________ is the pressure needed to ensure adequate blood flow to brain
CPP = MAP- ICP does not consider effect of cerebral vascular resistance
• CPP = Flow x Resistance
increase in cerebral vascular resistance= impaired blood flow to brain Normal CPP 60 – 100 mmHg
Transcranial Doppler Transcranial Doppler
Used to measure what?
Regulating CBF Regulating CBF
AS CPP decreases, autoregulation fails leads to decrease in CBF ** CPP < than 50 mmHg = ischemia, neuronal death ** CPP < 30 mmHg = not compatible with life
• ** Critical to maintain MAP when ICP elevated**
• Which patient’s may need a higher CPP?
What affects CBF? What affects CBF?
Cardiac, respiratory arrest diabetic coma systemic hemorrhage
* When autoregulation lost, CBF influenced by BP, hypoxia, catecholamines *
What affects CBF? What affects CBF?
C02, 02 hydrogen ions affect vessel tone PaCO2 vasoactive agent
- Increase in PaCO2= dilation
- Decrease in PaCO2 = constriction• decrease in 02 tension = accumulation of lactic acid, increasing acidic environment • increased dilation occurs; autoregulation may be lost
Changes in PressureChanges in Pressure
_________ is the expandability of the brain• Compliance = Volume/Resistance• Low compliance – small change in volume causes increase in pressure
• Intracranial Pressure-volume curve
- Stage 1 = total compensation- Stage 2 = at risk for increase in ICP- Stage 3 = great increase in ICP
- Stage 4 = ICP rises to lethal levels
Pressure -Volume CurvePressure -Volume Curve
Pressure ChangesPressure Changes
Loss of autoregulation = rise in BP Cushing’s Triad – what will you see?
neurological emergency!!
Stage 4 = herniation Intense pressure placed on ________. compression of _______ and ________ if herniation continues – what will occur?
Mechanisms of Increased ICP: Mechanisms of Increased ICP:
Mass lesion – like what? Cerebral edema – from what? Metabolic insult Result in impaired autoregulation, systemic hypertension
– leading to cerebral edema Increase in edema – distorts brain tissue – increase in?? ** To preserve tissue = maintain CBF!! **
** Any patient who becomes acutely unconscious, suspect what??
Cerebral EdemaCerebral Edema
Increase in tissue volume Leads to? Three types:
vasogenic cytotoxic interstital
Vasogenic Cerebral EdemaVasogenic Cerebral Edema
Most common type caused by changes in endothelial lining of cerebral capillaries leakage into extracellular space occurs mainly in white matter
Influenced by BP, site of brain injury, and extent of blood-brain barrier defect Can lead to coma headache may be first sign sharp assessment skills necessary; progresses quickly !
Cytotoxic Cerebral Edema Cytotoxic Cerebral Edema
disruption in integrity of cell membranes result of trauma; cerebral hypoxia or anoxia occurs most often in gray matter result of protein shift blood-brain barrier remains intact swelling and loss of cellular function
Interstitial Cerebral Edema Interstitial Cerebral Edema
result of rupture of CSF brain barrier hydrocephalus – what is this?
tx with ventricular shunt
can be caused by systemic water excess hyponatremia, water intoxication
Increased ICP: Manifestations Increased ICP: Manifestations
Change in LOC result of impaired CBF deprives cells of 02 interruptions of impulses from RAS
leads to abnormal state of complete or partial awareness – called what?
recorded by a EEG
Changes in LOC range from flat affect or change in orientation to coma
what will you see with coma?
Increased ICP: Manifestations
Changes in VS – caused by what?
Cushing’s triad – medical emergency!! What will you see? What about temperature?
Occular Signs dilation of pupil – which one? Indicates what?
sluggish, no response to light ptosis of eyelid blurred vision, diplopia papilledema – what is this?
Increased ICP: Manifestations
Decrease in Motor Function contralateral hemiparesis- meaning what?
hemiplegia decorticate vs. decerebrate posturing
what does this indicate?
Headache continuous, worse in the morning What can accentuate the pain?
Vomiting – will they complain of nausea?
Decorticate posturing- abnormal flexion Decerebrate posturing- abnormal extension
Diagnostic Studies
Identify presence and cause of increased ICP MRI CT EEG Angiography PET why not LP?
Monitoring of ICP:
Should be monitored in patients with GCS < or equal to 8; and abnormal CT or MRI
monitored in ICU Ventriculostomy
“gold standard” catheter inserted into lateral ventricle coupled to an external transducer directly measures pressure in ventricle facilitates removal of CSF intraventricular drug administration
Monitoring of ICP:
Fiberoptic catheter alternative technology sensor transducer within catheter tip placed within ventricle of brain direct measurement of brain pressure
Monitoring of ICP:
Subarachnoid bolt or screw placed through skull between arachnoid membrane and cerebral cortex does not allow CSF drainage ideal in patient’s with mild to moderate head injury can easily be converted to ventriculostomy if needed
ICP Monitoring: Complications
Infection – what increases risk?
> 5 days of monitoring use of ventriculostomy presence of CSF leak concurrent systemic infection
prophylactic antibiotics may be given!
Monitor CSF drainage for what?
Normal ICP Waveforms:
P1 – percussion wave represents arterial pulsations highest of the three waveforms
P2 – rebound or tidal wave reflects intracranial compliance when P2 > P1 = compromised compliance
P3 – dicrotic wave represents venous pulsations lowest waveform follows dicrotic notch
Intracranial pressure monitoring can be used to continuously measure ICP. The ICP tracing shows normal, elevated, and plateau waves. At high ICP the P2 peak is higher than the P1 peak, and the
peaks become less distinct and plateau.
CSF drain must be closed for at least _______ to ensure an accurate reading. Notify physician promptly for any abnormal change in waveform!!
What can cause an inaccurate ICP reading?
ICP Waveform:
Draining CSF:
May control ICP MD order: specific level to initiate drainage intermittent vs. continuous drainage
how long with intermittent?
opened with stopcock valve normal CSF 20 – 30 ml/hr
careful monitoring of volume essential!! prevent removal of too much CSF – how?
Draining CSF: Complications?
CSF removal based on institution policy or physician preference Complications:
ventricular collapse infection herniation subdural hematoma
Cerebral Oxygenation Monitoring (Pbt02):
LICOX – measures what? placed in white matter of brain continuous monitoring of Pbt02 – normal range?
low Pbt02 indicative of what? ability to measure _____________.
Jugular Venous Bulb Catheter measurement of Sjv02 measures cerebral oxygen supply and demand normal range 55% to 75% < 50% demonstrates what?
Can these measure ICP??
Collaborative Care:
Identify and TX underlying cause – obtain what? Normal causes?
Support brain function Ensure adequate oxygenation
ET tube, tracheostomy ABG’s – goal for Pa02? Goal for PaC02?
Surgical removal of mass or lesion hemicraniectomy
Diuretics, Corticosteroids
Collaborative Care: Drug Therapy
Mannitol – how does it work? Contraindicated when? monitor fluid and electrolyte status
Hypertonic Saline raises osmolality; decreases cerebral water content used concurrently with Mannitol requires frequent BP monitoring, Na+ levels – why?
Corticosteroids – like what? Side effects? treat vasogenic edema not recommended in head injury patients improve CBF, restore autoregulation
Collaborative Therapy:
What else may increase ICP?? maintain fever at 36 – 37 degrees C
Keep patient in quiet, calm environment Barbituates
total burst suppression?
Nutritional Therapy early feeding improves outcomes TF may be initiated 0.9% NS preferred IV solution
Nursing Management: ICP
Glasgow Coma Scale (GCS) assesses LOC opening of eyes – spontaneous, to pain? best verbal response – appropriate, confused? the best motor response – withdraw? Respond to verbal command?
What is the highest GCS for a fully alert person? When is a coma indicated?
Nursing Management: Neuro Assessment
compare pupils – ipsilateral or bilaterally dilated?
pupillary reaction – sluggish, fixed?
eye movements – doll’s eye?
palmar drift Why not use hand squeezing? assess BP, pulse, respiratory rate, temp – looking for what?
ICP: Nursing Intervention
Acute Intervention ** Maintenance of airway **
keep patient lying on one side suction as needed; < than 10 seconds in duration suction limited to 2 passes When is intubation required?
Prevent hypoxia Elevate HOB > than 30 degrees
Prevent Abdominal distention NG tube – when contraindicated?
ICP: Nursing Intervention
Manage pain, anxiety, fear Administer sedatives, analgesics, paralytics
alter neurologic state; temporary “drug suspension” Propofol (Diprovan) Precedex (continuous IV sedation)
Monitor ABG’s Monitor IV fluids/electrolytes – which ones?
SIADHProtect patient from harm (seizures, falls, etc. )