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. )