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92 Cards in this Set
- Front
- Back
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What blood gas affects ICP?
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CO2, increases it.
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What is the normal range of ICP?
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5-15mmHg
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How fast does blood flow through the brain?
Through the gray matter? Through the white matter? |
50ml/min
25ml/min 75ml/min |
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What is autoregulation?
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the automatic adjustment in the diameter of the cerebral blood vessels by the brain to maintain a constant blood flow during changes in arterial blood pressure
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What is the least MAP can be to maintain cerebral blood flow?
What is the most the MAP can be? |
50mmHg
150mmHg |
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What is the cerebral perfusion pressure, and how is it calculated?
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CPP is the pressure needed to ensure blood flow to the brain.
MAP - ICP = CPP CPP = Flow x Resistance....so if resistance goes up, cerebral flow goes down. |
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What is a normal range of cerebral perfusion pressure (CPP)?
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60-100mmHg
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What is compliance of the brain? What is the formula for it?
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The expandability of the brain.
Compliance = Volume/Pressure |
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What are the signs of ICP?
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headache, changes in LOC, pupil responsiveness
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What is Cushing's triad?
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The body trying to compensate for decreased autoregulation (decreased cerebral perfusion)
Systolic HTN with widening pulse pressure, bradycardia with a full and bounding pulse, and altered respirations THIS IS AN EMERGENCY!!! |
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What is herniation?
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ICP is at lethal levels...the brain is shifted from the compartment of greater pressure to a compartment of lesser pressure.
It pushes on the brainstem and kills you. |
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How do CO2, O2, and H affect the brain?
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When CO2 rises, it dilates the vessels
When O2 or H decreases, it dilates the vessels |
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When do you suspect ICP, always?
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A pt that becomes acutely unconcious.
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How do you calculate cerebral perfusion pressure?
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MAP - ICP = CPP
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What is the normal cerebral perfusion pressure?
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60-100 mmHg
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What causes vasogenic cerebral edema?
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Damages to the endothelial lining of the capillaries. Ex. Brain tumor, abscess, toxins
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What causes cytotoxic cerebral edema?
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SIADH secretion. Usually happens in GREY matter.
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What causes interstitial cerebral edema?
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CSF brain barrier ruptures. Usually happens with uncontrolled hydrocephalus or H20 intoxication.
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What does the reticular activating system control?
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Wakefulness
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What is Cushing's triad?
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Systolic HTN with a widening pulse pressure, bradycardia with a bounding pulse, irregular respirations
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What is Cushing's triad indicative of?
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Compression of brainstem, impending death
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How are brain masses manifested?
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Ipsilateral pupil non-response and contralateral hemiparesis
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What do decorticate and decerebrate positioning indicate?
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Decorticate - cerebral cortex interruption
Decerebrate - disruption of fibers in the brainstem. Decerebrate is WORSE! |
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What GI complaint would a person with ICP have?
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Projectile vomiting. Vomiting not preceded by nausea.
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With ICP, when do you do a lumbar puncture?
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You don't.
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What is the gold standard for measuring ICP?
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Ventriculostomy.
Make sure the transducer is level with the foramen of Morro (tragus of the ear.) |
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How do you measure ICP if there is a CSF drainage device?
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Close the drain for 6 minutes for an accurate reading.
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What is the normal production of CSF fluid?
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20-30ml/hr with a total CSF volume of 90-150ml
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How do you drain CSF fluid?
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Intermittant - open stopcock for 2-3 min then close it on ventriculostomy.
Continuous - monitor the volume of CSF drained closely |
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What is the LICOX brain tissue cathetar?
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Measures brain tissue oxygen pressure - should be 20-40mmHg
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What about fever and ICP?
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Don't want it! Cool the pt down with cooling blankets, tepid sponge baths. Prevent shivering by cooling them down slowly.
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What about ABG's?
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You want the PaO2 at >100mmHg and the PaCO2 at about 30-35mmHg to prevent vasodilation. May need to mechanically ventilate them to achieve this.
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What should we know about mannitol?
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Give through a filtered cathetar.
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Which corticosteroid do we use with ICP?
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Dexamethasone!! But not with head-injured pts
Monitor I&O, Na, and glucose level q6hour. |
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What do we use barbiturates for in ICP?
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Reduce cerebral metabolism. Total burst suppression (absence of spikes on the EEG) indicates max effect has been achieved.
pentobarbital, thiopental |
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What is the preferred IV fluid for piggybacks with ICP?
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NS
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What 3 things does the Glasgow Coma Scale measure?
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Eye opening, verbal response, motor response.
Score of <8 = coma |
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How are eye movements illicited in the unconscious pt?
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Oculocephalic refles (doll's-eye reflex). Turn pts head briskly to the lft or rt while holding the eyelids open. Normal response is movement of the eyes across the midline in the direction opposite that of the turning.
Oculovestibular reflex |
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How do you test strength of upper extremities?
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Ask pt to squeeze your hand or do the palmar drift test
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How do you position the client in a coma?
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On their side. Snoring indicates obstruction and requires immediate attention!
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Why do you use an NG tube with an ICP pt?
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To prevent abdominal distention as it interferes with respiratory function
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What kind of meds are neuromuscular blocking agents?
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vecuronium (Norcuron), cisatracurium besylate (Nimbix)
Paralytics. Do not kill pain. |
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What should the serum osmolality be?
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200-300mOsm/kg
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What anxiolytics do you AVOID with increased ICP pts?
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Benzodiazapines - their half life is too long.
You want to use dexmedetomidine (Precedex) b/c you can get a neuro assessment w/o altering the dose. Don't use more than 24 hours. Atropine is the antidote. |
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With ICP watch for diabetes insipidus. What rx do you give for diabetes insipidus?
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Desmopressin or vasopressin. (These ARE ADH). Watch for tachycardia, seizures, nasal stuffiness, rhinnorhea.
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When do deaths from head traumas occur?
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Immediately after injury, 2 hours, 3 weeks.
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What factors predict a poor prognosis with ICP?
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Intracranial hematoma, older age of pt, abnormal motor responses, impaired or absent eye movements or pupillary light reflexes, early systained hypotension, hyposemia, hypercapnia, ICP >20mmHg.
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What confirms that the skull fracture has traversed the dura?
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Rhinorrhea or otorrhea (CSF leakage from nose or ears)
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What are pts with CSF leaks at high risk for?
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Meningitis. Give them prophylactic antibiotics.
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How do you test for CSF?
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Halo test, test for glucose UNLESS blood is in the fluid b/c blood already has glucose.
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What types of skull fractures are there?
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Linear - break in continuity of bone
Depressed - inward indention Simple - linear or depressed Comminuted - Multiple linear fractures with fragmentation of bone in many pieces Compound - Depressed skull fracture and scalp laceration with communicating pathway to intracranial cavity |
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What is Battle's sign?
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Oval-shaped bruise behind ear in mastoid region indicating temporal, parietal, or basilar skull fracture.
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What are the typical signs of concussion?
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Brief disruption in LOC, amnesi regarding the event, headache.
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What is postconcussion syndrome?
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Seen 2 weeks-2months after injury. Headache, lethargy, personality/behavioral changes, shortened attention span, decreased short-term memory, changes in intellectual ability.
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What are the signs of diffuse axonal injury?
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Axon disconnection. Vegetative state. Decreased LOC, increased ICP, decortication or decerebration, global cerebral edema
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What do you do for a lacerated brain?
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Antibiotics until meningitis is ruled out and then prevent ICP.
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How does brain hemorrhage manifest?
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Unconsciousness, hemiplegia on the contralateral side, dilated pupil on the ipsilateral side.
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With a contusion, what is coup, contre-coup theory?
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coup is where the brain is hit, contre coup is the rebound
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What are the classic signs of an epidural hematoma?
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Initial period of unconsciousness at the scene, brief lucid interval followed by a decrease in LOC. Needs rapid sx intervention.
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When do subdural hematomas occur?
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24-48hours after injury (acute)
2days-2weeks (subacute) chronic develops over weeks to months |
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What is the best test for head trauma?
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CT scan
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What is emergency management of a head injury?
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ABC's.
Administer O2 via non-rebreather mask. 2 large-bore catheters, infusing NS or lactated Ringer's Control external bleeding with sterile pressure dressing Assess for rhinorrhea, otorrheascalp wounds, Stabilize cervical spine Remove pts clothing Ongoing monitoring: Keep pt warm |
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What kind of meds do we NOT want a head injury pt on?
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Anticoagulants
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What do you do for diplopia?
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Eye patch.
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How do you help with raccoon eyes?
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Use cold then later warm compresses.
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If there is a CSF leak, what do we NOT use that we usually use with other ICP pts?
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NG tubes and NG suctioning b/c of risk of meningitis
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What teaching do we do for head injury pts?
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NO LIST! NO:
drinking, driving, guns, work with hazardous implements and machinery, unsupervised smoking |
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What is the most common primary brain tumor?
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Glioma. Glioblastoma multiforme is the most common, and it also has the poorest prognosis.
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What ethnicity gets more brain tumors?
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Whites
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What is a brain tumor headache like?
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Worse at night, may awaken the pt. Constant, throbbing. Seizures.
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When do we suspect brain tumors?
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When there is new onset of seizures or adult-onset migraines.
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What corticosteroid do we LOVE in neuro?
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DEXAMETHASONE (DECADRON)
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What kind of chemo drugs do we use with brain tumors?
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nitrosoureas (carmustine (BCNU), lomustine (CCNU)) b/c they cross the blood-brain barrier.
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What are the nursing interventions specific to brain tumors?
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Close supervision of activity, use of side rails, judicious use of restraints, appropriate sedatives, padding of areas around the bed, calm reassuring approach, keep environmental stimuli to a minimum, seizure precautions
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During brain surgery, is the hair shaved?
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Yes, to prevent contamination and to allow for better exposure. Usually removed in the OR after induction of anesthesia.
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How do we control pain after brain sx?
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Short acting opiods like morphine, fentanyl, and propofol. NO PHENERGAN. (b/c it increases somnolence)
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How do we position pts after brain sx?
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It the incision is in the anterior or middle fossa, HOB 30-45 degrees
If the incision is in the posterior fossa or there is a burr hole, HOB flat or up 10-15 degrees. DO NOT POSITION PTS ON THE OPERATIVE SIDE. |
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With the cooling blankets, what nursing intervention do we do?
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Wrap the extremities in towels or blankets covered with a sheet to protect them from forstbite.
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What organisms tend to cause brain absesses?
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Streptococci and Staphylococcus aureus. Use antimicrobials.
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What normally causes bacterial meningitis?
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Streptococcus pneumoniae and neisseria meningitidis. Bacterial menintitis is usually secondary to VIRAL RESPIRATORY DISEASE.
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What are the symptoms of bacterial meningitis?
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Fever, headache, n/v, nuchal rigidity, photophobia, decreased LOC, increased ICP, seizures, skin rash, petechiae.
Complications can include blindness and deafness. Vision may come back, but hearing will not. |
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What is Waterhouse-Friderichsen syndrome?
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Complication of meningococcal meningitis. Petechiae, DIC, adrenal hemorrhage, circulatory collapse.
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What are the most serious complications of meningitis?
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DIC and shock
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What is the health promotion a nurse should do with a meningitis pt?
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Give the people around them prophylactic antibiotics.
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What can the nurse do for the pt with meningitis?
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Put them in a position of comfort, probably curled up with the head slightly extended.
Darken the room, put a cool cloth over their eyes. Minimize environmental stimuli for the delirious pt, and avoid restraints. Cooling blankets. Replace fluids from diaphorsis as 800ml/day plus 100ml additional for each degree of temp above 100.4. |
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What kind of isolation does the meningitis pt need?
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RESPIRATORY ISOLATION!! It's highly contagious!!
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What are the most common causes of viral meningitis?
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Enteroviruses, arboviruses, HIV, herpes simplex
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What is encephalitis?
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An acute inflammation of the brain.
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What do you think if an adult over 50 develops encephalitis or meningitis in summer or early fall?
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West Nile.
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How do you prevent encephalitis?
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Mosquito control.
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What are the symptoms of rabies?
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2-14 days after exposure:
flu like symptoms, pain, paresthesias, numbness 2-7 days later: agitation, hypersalivation, hydrophobia, dysarthria, vertigo, diplopia, hallucinations, hyperactive reflexes, nuchal rigidity, positive Babinski's 7-10 days after that: Coma, flaccid paralysis, apnea, hydrophobia, seizures, death. |
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What are the symptoms of a subdural hematoma?
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Pt develops decreased LOC and a headache within 48 hours of injury.
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