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Neurologic System
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AACN CCRN Review
Neurologic System
Presenter: Mary Kay Bader RN, MSN, CCRN, CNRN, CCNS, FAHA
Clinical Nurse Specialist Mission Hospital Mission Viejo, CA
Neurologic System
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Adult CCRN Review Neurologic System
Mary Kay Bader RN, MSN, CCRN, CNRN, CCNS, FAHA
Topics o Increased intracranial pressure o Head trauma o Ischemic stroke o Hemorrhagic stroke o Neurologic infectious diseases o Seizures and epilepsy o Status epilepticus o Brain tumors
Increased Intracranial Pressure o Classification
Increases in tissue volume Increases in blood volume Increases in cerebrospinal fluid (CSF) volume Congenital abnormalities Metabolic
o Pathophysiology o Signs/Symptoms Increased Intracranial Pressure (ICP)
Decrease in level of consciousness (LOC) Motor
Contralateral motor deficit Cranial nerves
Ipsilateral pupil abnormalities Headache and/or vomiting Cushing’s triad
Bradycardia Widening pulse pressure Respiratory arrest
o ICP Monitoring Indications for monitoring ICP:
GCS 3 – 8 CT reveals abnormality
o Types of monitoring devices o Intraparenchymal bolt Ventriculostomy
Intracranial pressure Normal: 0‒15 mm Hg
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Elevated: >20 mm Hg
o Cerebral Blood Flow (CBF) CBF – cerebral perfusion pressure (CPP)/cerebrovascular resistance (CVR) CPP = mean arterial pressure (MAP) – ICP
Injured brain optimize CPP Use target of 50–70 mm Hg
o Autoregulation o Cerebral Blood Flow
Autoregulation Vasomotor control
Intact: Increase in CPP causes vasoconstriction and decrease in ICP
Vasomotor reactivity failure: Increase in CPP causes vasodilation and increased ICP Flow metabolism
metabolism CBF Metabolic substances
PaO2
PaCO2
pH—ie, acidosis = vasodilation o Interventions
Head of bed (HOB)/neck positioning Quiet environment Monitor ICU and drain CSF if ICP > 20 mm Hg Airway and breathing
PaO2 and PaCO2
Target PaO2 > 80 mm Hg and PaCO2 35 – 40 mm Hg
Decrease PaCO2 30–35 mm Hg if impending herniation Circulation
Maintain CPP >50–70 mm Hg Maintain euvolemia/vasopressors
Sedation and analgesia as indicated for control of ICP Normothermia
o Secondary Interventions Mannitol
0.25–1 g/kg Replace fluids lost to maintain euvolemia
Hypertonic saline 3%—200 mL over 20 minutes 5%—150 mL over 20 minutes 7%—100 mL over 20 minutes 23.5%—15–20 mL
o Tertiary Interventions Decompressive hemicraniectomy
Large Early
Temperature control Hypothermia for refractory increased ICP
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Barbiturate coma
Uncontrolled Increased ICP: Progression to Brain Death o President’s Commission report on guidelines for determination of brain death
culminated in a legal definition and established the Uniform Determination of Death Act In individual who has sustained either:
Irreversible cessations of circulatory and respiratory functions
Irreversible cessation of all functions of the entire brain
Uncontrolled Increased ICP: Progression to Brain Death o Determining brain death—4 steps
o Establish irreversible and proximate cause of coma
History, examination, neuroimaging, and laboratory o Achieve a normal or near-normal core temperature
> 35⁰ C (as close to 36⁰ C) o Achieve a normal systolic BP >100 mm Hg o Perform one neurologic exam (acceptable in most states)
Some states require more than one exam and some may specify a certain level of expertise (eg, neurologist/neurosurgeon)
o Perform one neurologic exam (acceptable in most states)
Coma: must lack all level of responsiveness (no eye opening, no eye movement, no motor response to stimuli)
Absence of brainstem reflexes (fixed pupils, absent dolls eyes/cold calorics, absent corneal/swallow/gag, and no facial)
Apnea: absence of spontaneous breathing (allow PaCO2 >60 mm Hg) o 8–10 min support with 100% FiO2 via O2 to ET tube
Ancillary tests: EEG, cerebral angio, nuclear scan blood flow o Not used to confirm brain death and cannot replace the clinical exam
o Time of brain death is:
Time the PaCO2 reaches the target level and absent spontaneous breathing
If unable to do apnea, time of ancillary test officially interpreted
Review Questions
Question #1 —A brain-injured patient was admitted 4 hours ago after sustaining a large subdural hematoma (SDH) which was evacuated surgically. AN ICP monitor with CSF drainage was placed by the MD. The ICP increases to 24 mm Hg while the patient’s CPP is 64 mm Hg. After draining CSF, the first intervention would be to lower the ICP by: o Lowering the HOB o Administering hypertonic saline or mannitol o Instituting a pentobarbital coma o Lowering the PaCO2 to 28 mm Hg
Question #1 rationale— A brain-injured patient was admitted 4 hours ago after sustaining a large SDH which was evacuated surgically. AN ICP monitor with CSF drainage was placed by the MD. The ICP increases to 24 mm Hg while the patient’s CPP is 64 mm Hg. After draining CSF, the first intervention would be to lower the ICP by: o Lowering the HOB. Lowering the HOB would increase the ICP o Administering hypertonic saline or mannitol
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o Instituting a pentobarbital coma. Instituting a pentobarbital coma would be a tertiary intervention
o Lowering the PaCO2 to 28 mm Hg. Lowering the PaCO2 to 28 mm Hg would decrease CBF and create ischemia, especially on day 1 of TBI when cerebral blood flow is often critically reduced; this should be avoided
Question #2 —It is day 4 of FZ’s hospitalization following a severe traumatic brain injury (TBI). He has experienced an increase in urine output (1000 mL) over the past 3 hours. His MAP has decreased to 75 mm Hg and his ICP had increased to 30 mm Hg, resulting in a CPP of 45 mm Hg. If FZ has intact autoregulation, the most appropriate intervention would be to: o Administer 500 mL fluid bolus to increase the MAP and decrease the ICP o Administer 50 g of mannitol to reduce the ICP o Begin nicardipine to lower the MAP and ICP o Do nothing, since the MAP/ICP/CPP are within normal ranges
Question #2 rationale—It is day 4 of FZ’s hospitalization following a severe TBI. He has experienced an increase in urine output (1000 mL) over the past 3 hours. His MAP has decreased to 75 mm Hg and his ICP had increased to 30 mm Hg, resulting in a CPP of 45 mm Hg. If FZ has intact autoregulation, the most appropriate intervention would be to: o Administer 500 mL fluid bolus to increase the MAP and decrease the ICP o Administer 50 g of mannitol to reduce the ICP. Administering 50 g of mannitol to reduce the
ICP may significantly lower the BP resulting in a further increase in ICP o Begin nicardipine to lower the MAP and ICP. This would actually increase the ICP o Do nothing, since the MAP/ICP/CPP are within normal ranges. The ICP is elevated (>20 mm
Hg) and the CPP is not in the ideal range of 50–70 mm Hg
Head Trauma Etiology of Brain Injury
o Mechanisms of injury Trauma
Blunt
Penetrating
Blast
Pathophysiology of Brain Injury o Primary injury
Trauma
Skull integrity
Brain integrity o Focal injuries o Diffuse injuries
Classification o Secondary injury r/t event
Cerebral edema Changes in CBF Cellular
Types of Primary Injuries o Scalp
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o Skull
Primary Injuries o Cerebral injuries
Diffuse Focal
Diffuse Injury: Concussion o Stretch injury of axons o Temporary disturbance in neurologic function o Grades 1 – 3 o Post-concussive syndrome
Diffuse Axonal Injury o Shearing
Disruption of axons CT
Degrees of coma Control of ICP Prolonged Recovery varies
Epidural Hematoma (EDH) o Associated with linear skull fracture
Children may not have skull fracture with epidural Rare in older adults
o Location: 75% temporal region o CT: biconvex o Exam o Treatment
Removal of hematoma Post-op monitoring of neurologic status and determining any cognitive deficits
SDH o Associated with high-velocity deceleration o Timing and cause Acute within 24–48 hours
Rupture of bridging cortical veins
Increased ICP/contusions Subacute: 48 hours to 10 days Chronic: 10 days to 6 weeks
Rupture of bridging veins across parasagittal space o CT o Clinical presentation
Acute SDH
Subacute SDH o Subacute SDH
Usually unilateral isodensity 2 -10 days after event
o Chronic SDH Usually bilateral isodensity 2 – 6 weeks after event
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Management of SDH o Acute
Acute surgical decompression Synchronous with increased ICP management
o Subacute and chronic Burr holes for removal of fluid Flat for 1–2 days Gradual elevation of HOB Evaluation for deficits
Cerebral Contusions o Types
Fracture Coup Countercoup Herniation Surface Gliding (focal hemorrhage in cortex/subjacent white matter found in diffuse axonal
injury) o Frequently frontal or temporal regions o Vasogenic edema and central necrosis o Diagnosis: CT and exam
Focal Injury: Cerebral Contusions o Care Priorities
Manage ICP Manage life support systems Assessment of deficits Education of patient/family
Head Injury Assessment o History of event o Severity of injury based on Glasgow Coma Scale (GCS)
Mild 13–15 Moderate 9 –12 Severe 3–8
o Signs of increased ICP and evidence of injury o Diagnostics
Interventions o Airway
Oxygenation: airway and oxygen Ventilation:
Initial: PaCO2 35–45 mm Hg
Phase II (days 2–6): PaCO2 may decrease BP and volume
2007 Brain Trauma Foundation Guidelines: CPP 50–70 mm Hg
Fluids/vasopressors Mannitol or hypertonic saline Positioning
HOB 30⁰ with neck midline
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Interventions o Draining CSF for ICP > 20 mm Hg o Temperature regulation
Keep normothermic (37⁰ C) o Refractory ICP
Decompressive hemicraniectomy Mild hypothermia
o Nutrition o System support o Rehab
Review Questions Question #3—JR, a 34-year-old male, fell from a ladder and sustained a severe TBI. His GCS on
arrival was 1-3-1 with pupils at 2 mm and minimally reactive to light. CT scan of brain shows multiple punctate hemorrhages along with an acute EDH. The neurosurgeon evacuated the bleed and placed an ICP/brain oxygen monitor into the brain. On admission to ICU: GCS 1-4-1; MAP 80 mm Hg; ICP 10 mm Hg; CPP 70 mm Hg, PbtO2 12 mm Hg (normal 20–40 mm Hg); PaCO2 30 mm Hg; CVP 10 mm Hg. What is your first intervention?
o Give 250 mL NS to increase CVP o Administer mannitol g IV push o Decrease the tidal volume or rate to increase the PaCO2 o Do nothing, since the patient’s parameters are within the normal zone
Question #3 rationale—JR, a 34-year-old male, fell from a ladder and sustained a severe TBI. His GCS on arrival was 1-3-1 with pupils at 2 mm and minimally reactive to light. CT scan of brain shows multiple punctate hemorrhages along with an acute EDH. The neurosurgeon evacuated the bleed and placed an ICP/brain oxygen monitor into the brain. On admission to ICU: GCS 1-4-1; MAP 80 mm Hg; ICP 10 mm Hg; CPP 70 mm Hg, PbtO2 12 mm Hg (normal 20–40 mm Hg); PaCO2 30 mm Hg; CVP 10 mm Hg. What is your first intervention?
o Give 250 mL NS to increase CVP. Incorrect; the CVP and CPP are normal o Administer mannitol g IV push. Incorrect; the ICP is normal o Decrease the tidal volume or rate to increase the PaCO2 o Do nothing, since the patient’s parameters are within the normal zone. Incorrect,
because the patient’s oxygen level is critically low in the brain
Question #4—EG, an 80-year old male, was previously independent and able to care for himself. His daughter stated he is now unable to walk and is confused/disoriented. A CT scan of the brain reveals bilateral large chronic SDH. The neurosurgeon evacuated both SDH and has placed a Jackson-Pratt drain to gravity. The patient was extubated post-op. Where should the HOB be maintained? o HOB flat for 24–48 hours o HOB at 15⁰ for 10 days o HOB at 30⁰ to reduce ICP o HOB at 45⁰to reduce ICP
Question #4 rationale—EG, an 80-year old male, was previously independent and able to care for himself. His daughter stated he is now unable to walk and is confused/disoriented. A CT scan
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of the brain reveals bilateral large chronic SDH. The neurosurgeon evacuated both SDH and has placed a Jackson-Pratt drain to gravity. The patient was extubated post-op. Where should the HOB be maintained? o HOB flat for 24–48 hours o HOB at 15⁰ for 10 days. Incorrect, due to the position and length of time o HOB at 30⁰ to reduce ICP. Incorrect because the ICP is usually normal and the brain needs to
re-expand into the space occupied by the blood clot. Typically, elderly individuals undergo significant brain atrophy, and thus have more space in the cranial vault
o HOB at 45⁰to reduce ICP. Incorrect because the ICP is usually normal and the brain needs to re-expand into the space occupied by the blood clot. Typically, elderly individuals undergo significant brain atrophy, and thus have more space in the cranial vault
Stroke Ischemic Stroke
Risk factors Signs/symptoms
FAST
Face, arm, speech, time
Motor weakness
Asymmetrical smile
Difficulty speaking
Numbness
Visual changes
Difficulty swallowing Use NIHSS to assess
Full
Abbreviated Etiology
Thrombotic 20-25%
Embolic 20%
Lacunar 20%
Cryptogenic 30% Pathophysiology
Reduced blood flow
Importance of collateral flow
BP management
Impact of glucose and temperature
Three factors affecting outcomes
Time dependent
Degree of ischemia
Collateral circulation
Pathophysiologic issues related to stroke Edema and increase ICP
Occurs as natural evolution of insult
Minimized if perfusion restored
Assess for change in neurologic status
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Do not medicate with sedation agents unless monitoring for increased ICP
Prepare for CT
Ischemic Stroke Intervention
ABC
Supplemental O2 for SaO2 <94% BP management
Assess BP and Treat
No tPA: SBP >220 mm Hg; DBP >120 mm Hg or MAP >130 mm Hg
tPA: SBP >185 mm Hg or DBP >110 mm Hg
Only use labetalol or nicardipine
Monitoring Neuro exam every 15 minutes x 4 until treatment decision made
IV and labs
Diagnostics CT scan
No hemorrhage
No edema 12-lead ECG: NSR
Ischemic Stroke Time window: candidates for tPA Intravenous tPA
Time window was <3 hours
Time window now moved to 4.5 hours
Scientific Advisory: tPA o tPA should be administered to eligible patients who can be treated in the time period of 3 to
4.5 hours after stroke
Intravenous tPA: Indications o Patient symptoms <4.5 hours from symptom onset
CT scan excludes hemorrhage NIH stroke scale >4 Isolated aphasia Age >18
o Note exclusions for 3– 4.5 hour IV tPA Age >80 years Taking oral anticoagulants NIHSS >25 Combination of history of prior stroke and diabetes
Ischemic Stroke o Decision point
Thrombolysis: up to 6 hours
IV 3–4.5 hours
IV/IA 4.5 hours
IA 6 hours (off label) Merci retrieval/penumbra device/solitaire
Up to 8 hours Supportive care
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Aspirin 325 mg rectally by 48 hours
Infusion Guidelines tPA o Preparation of IV tPA drip
0.9 mg/kg 10% IV over 1–2 minutes 90% IV over 60 minutes
o Administration of tPA Monitor VS: every 15 minutes x 2 hours, every 30 minutes x 6 hours, then every hour x
16 hours Treat BP accordingly
Ischemic Stroke o tPA
BP considerations: treatment
SBP >185 mm Hg/ DBP >110 mm Hg Administration: IV
Postinfusion care: Treat systolic BP >180 mm Hg and diastolic BP >105 mm Hg Supportive care
Do not drop BP unless: o Systolic BP >220 mm Hg/diastolic BP >120 mm Hg o Treat with labetalol or nicardipine
o VS/neuro checks every 1 – 2 hours NIHSS
o Support airway/O2/pulse oximetry o Cardiac telemetry o HOB flat vs 30⁰
Flat if no signs of increased ICP – supports improved flow HOB 30⁰ if signs of increased ICP
o NPO until swallow assessment o Temperature management
Treat temperature >98.6⁰ F o Hydrate/control serum glucose <180 mg/dL o Observe neurologic status o Medications: statins and antiplatelet agents o Begin nutrition o Early mobility o Prevent complications
Aspiration: NPO until swallow assessment DVT UTI
o Educate family o Secondary stroke prevention
Review Questions Question #5—LL, a 65-year-old female, developed an acute onset of left-sided weakness with
neglect to the left side at 12:35 PM. Her speech became slurred and she didn’t know where she was. LL’s son brought her to the ED, where a CT scan of the brain revealed no hemorrhage. A CTA demonstrated an occlusion of the right middle cerebral artery. The ED physician/neurologist
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has ordered IV tPA. It is 2 hours, 50 minutes since symptom onset. The patient’s last BP was 190/100 mm Hg. Your first action is: o Administer the tPA 0.9 mg/kg IV dose because there is only 10 minutes in the treatment
window o Administer the tPA 0.6 mg/kg IV dose and labetalol 10 mg IVP at the same time o Start IV nitroprusside to reduce the BP o Administer 10–20 mg IV labetalol to reduce the BP prior to administering the tPA
Question #5 rationale—LL, a 65-year-old female, developed an acute onset of left-sided weakness with neglect to the left side at 12:35 PM. Her speech became slurred and she didn’t know where she was. LL’s son brought her to the ED, where a CT scan of the brain revealed no hemorrhage. A CTA demonstrated an occlusion of the right middle cerebral artery. The ED physician/neurologist has ordered IV tPA. It is 2 hours, 50 minutes since symptom onset. The patient’s last BP was 190/100 mm Hg. Your first action is: o Administer the tPA 0.9 mg/kg IV dose because there is only 10 minutes in the treatment
window. Incorrect because controlling the BP must be done prior to administering tPA o Administer the tPA 0.6 mg/kg IV dose and labetalol 10 mg IVP at the same time. Incorrect
because the dose of tPA is incorrect and the BP must be lowered prior to the administration of tPA
o Start IV nitroprusside to reduce the BP. Incorrect because labetalol and nicardipine are the first two drugs of choice when lowering BP in acute stroke
o Administer 10–20 mg of IV labetalol to reduce the BP prior to administering the tPA
Question #6 —BP, a 90-year-old female, presents with acute onset of aphasia and right-sided hemiparesis. She was last seen normal 12 hours ago. Her PT 195/105 mm Hg. Which medication do you anticipate the physician team to order first? o Labetalol 10 mg IV to lower the BP o tPA 0.9 mg IV (10 % IV bolus/90% drip over 60 minutes) o Aspirin 325 mg PO o Aspirin 325 mg per rectum
Question #6 rationale—BP, a 90-year-old female, presents with acute onset of aphasia and right-sided hemiparesis. She was last seen normal 12 hours ago. Her PT 195/105 mm Hg. Which medication do you anticipate the physician team to order first? o Labetalol 10 mg IV to lower the BP. Incorrect because the BP threshold in the non-tPA
patient is 220/120 mm Hg o tPA 0.9 mg IV (10 % IV bolus/90% drip over 60 minutes). Incorrect since the patient
symptoms are >4.5 hours o Aspirin 325 mg po. Incorrect since the patient may have difficulty swallowing and needs to
have her swallow evaluation prior to receiving any oral medications o Aspirin 325 mg per rectum
Hemorrhagic Stroke
Intracerebral Hemorrhage (ICH) o Usually a result of hypertension o Releases toxins that leads to vasospastic activity o Local decrease in perfusion o Global decrease in perfusion
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o Cellular changes
SAH: Aneurysm o Aneurysms o Occur at bifurcation o Defect in artery o Rupture point o Bleeds into subarachnoid space, brain tissue or ventricles o Danger
Rebleeding Vasospasm
Vascular Malformations o Developmental vascular anomalies o Result from error in embryonic vascular network o 86% of all SAH
Only 1% of all strokes Ratio of AVM to aneurysm 1:10
o Symptom onset 80% between 20–40 years of age 20% before age 20
Pathophysiology : Ruptured AVM o Rupture causes hemorrhage, increased ICP, and hemispheric damage
Hemorrhagic Stroke o Assessment: ICH
Headache, altered LOC, and nausea/vomiting Motor weakness and sensory changes Cranial nerve deficits Signs of increased ICP
o Assessment: SAH “Worst headache of life” Meningeal: photophobia and nuchal rigidity Nausea/vomiting and dizziness Focal deficits, ie, 3rd nerve
o Aneurysms—Assessment grading: Hunt and Hess scale I: alert, no deficit, and minimal headache II: awake, CN palsy, mild to severe headache III: drowsy, confusion, and mild focal deficit IV: unresponsive and hemiplegia V: comatose, moribund, and extensor posturing
o Diagnostic work-up Lumbar puncture
Presence of RBCs/WBCs
Elevated protein CT scan
Presence of SAH Angiogram Spiral CT angiogram MRI/MRA
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o Management of ICH Medical management of ICH
Surgery vs medical management vs palliative care
Ventriculostomy and ICP monitoring Team Management
ABC
Airway/ventilation
BP control
Circulation: Normovolemia and VTE prophylaxis ICP control: CSF drainage and mannitol vs hypertonic saline bolus
System support o Management of SAH
Pre-op
BP control (SBP < 140 – 15 mm Hg)
Frequent assessments to monitor for neurologic deterioration due to hydrocephalus or rebleeding
Surgical clipping vs coiling o Team management of SAH
Pre-op Post-op
ABC:
PaO2 >80 mm Hg PaCO2 >35 mm Hg
Watch for myocardial stunning
Target BP 120 – 15 mm Hg unless vasospasm present
ICP control: CSF drainage
Vasospasm Most likely days 4 - 14 o BP management and double H therapy
Keep BP normalized until vasospasm begins If vasospasm, then elevate BP
o Nimodipine o Watch for change in exam and/or sodium drop and diuresis
Interventions o NG o IV fluids o Maintain anticonvulsants o Examine patient for injury o Treat hyperthermia o Begin nutrition o Early mobility o Psychological support
Review Questions
Question #7—SS, a 50-yearl-old female, presents with the worst headache of her life and photophobia. Her neuro exam is otherwise normal. CT scan of brain shows a large SAH from a possible cerebral aneurysm. Her BP is 170/100 mm Hg. Initially, the physician will want the BP treated if: o Systolic BP >90 mm Hg
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o Systolic BP >150 mm Hg o Systolic BP >180 mm Hg o Systolic BP >220 mm Hg
Question #7 rationale—SS, a 50-year-old female, presents with the worst headache of her life and photophobia. Her neuro exam is otherwise normal. CT scan of brain shows a large SAH from a possible cerebral aneurysm. Her BP is 170/100 mm Hg. Initially, the physician will want the BP treated if: o Systolic BP >90 mm Hg. A SBP <90 mm Hg would not be beneficial to cerebral perfusion o Systolic BP >150 mm Hg o Systolic BP >180 mm Hg. This range is too high and may contribute to rebleeding of the
aneurysm o Systolic BP >220 mm Hg. This range is too high and may contribute to rebleeding of the
aneurysm
Question #8—BP, a 52-year old female, was admitted to the ICU following rupture of a cerebral aneurysm and large SAH. CT scan of her brain revealed acute hydrocephalus. The most likely cause of BP’s hydrocephalus is: o Cerebral aneurysm exerting pressure on the choroid plexus in the ventricles, limiting the CSF
absorption o Blood in subarachnoid space mixing with CSF and occluding the arachnoid villi, which helps
reabsorb CSF in the brain o Overproduction of CSF from the aneurysm rupture o Reduced absorption of CSF by the choroid plexus
Question #8 rationale—BP, a 52-year old female, was admitted to the ICU following rupture of a cerebral aneurysm and large SAH. CT scan of her brain revealed acute hydrocephalus. The most likely cause of BP’s hydrocephalus is: o Cerebral aneurysm exerting pressure on the choroid plexus in the ventricles, limiting the CSF
absorption. The choroid plexus makes CSF. It does not absorb CSF o Blood in subarachnoid space mixing with CSF and occluding the arachnoid villi, which
helps reabsorb CSF in the brain o Overproduction of CSF from the aneurysm rupture. Aneurysmal rupture does not increase
CSF production by the choroid plexus o Reduced absorption of CSF by the choroid plexus. CSF is absorbed by the arachnoid villi
Question #9—SS is now 10 days post aneurysm rupture. The aneurysm was surgically clipped on day 2. SS began complaining of a headache this morning. Her motor exam has changed in the last 2 hours with her right arm motor strength has diminished from 5/5 to 3/5. She is having word-finding problems with her speech. The most likely explanation for this change in status is: o Increased ICP
o Rebleeding
o Ischemic stroke
o Vasospasm
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Question #9 rationale—SS is now 10 days post aneurysm rupture. The aneurysm was surgically clipped on day 2. SS began complaining of a headache this morning. Her motor exam has changed in the last 2 hours with her right arm motor strength has diminished from 5/5 to 3/5. She is having word-finding problems with her speech. The most likely explanation for this change in status is: o Increased ICP. Although cerebral edema is possible after SAH, a change in LOC should occur
o Rebleeding. Since the aneurysm has been surgically repaired, this complication is unlikely
o Ischemic stroke. If vasospasm is not treated, the end result could be an ischemic stroke
o Vasospasm
Neurologic Infectious Diseases
Meningitis
o An inflammation of the meninges
o Primary causes
Bacterial
Viral
Fungal
Other causes include parasites and cancer
Meningitis: Causative Agents
Bacterial Viral Fungal
Streptococcus
pneumonia
Neisseria meningitides
Haemophilus influenza
Group B streptococcus
Escherichia coli
Listeria monocytogenes
Mycobacterium
tuberculosis
Treponemia pallidum
(neurosyphilis)
Enteroviruses:
Coxsackieviruses
Echoviruses
Polioviruses
Arborviruses:
Transmitted by arthropod
vectors (mosquitos or ticks)
(eg, St. Louis encephalitis)
Other:
Mumps virus; measles virus;
rubella virus; lymphocytic
choriomeningitis virus; HIV;
herpesvirus, including herpes
simplex virus; varicella-zoster
virus, cytomegalovirus, and
Epstein-Barr
Cryptococcus
neoformans
Coccidiodes immitis
Candida albicans
Blastomyces dermatitidis
Histoplasma capsulatum
Paracoccidiodes
brasiliensis
Sporothrix schenckii
Pseudallescheria boydii
Aspergillus fumigates
Meningitis
o Pathophysiology
Access routes: open wound, mucous membrane, or infected tissue
Direct
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Penetrating wounds, skull fractures, neuro operative procedures, LPs, ICP, otitis
media, sinusitis, or osteomyelitis
Hematogenous
Septicemia/bacteremia, septic emboli, bacterial endocarditis, URI, pelvic
abscess
CSF leak: rhinorrhea/otorrhea
Meningitis
o Pathophysiology
Bacterial process
Colonization: invades tissue/gains access to blood
Crosses blood‒brain barrier
No host immune defense in CSF
Rapid replication of bacteria
Rapid increase in neutrophils
Lysis of bacteria
Produces exudate and inflammation of meninges
Cerebral edema, vasculitis, infarctions, hydrocephalus, and increased ICP
Bacterial Meningitis: Assessment
o Subjective data
Varies depending upon the pathogen
Headache, neck or back pain, photophobia, and malaise
o Objective data
Clinical triad: fever, nuchal rigidity, altered mental status
Meningeal irritation: headache, nuchal rigidity, photophobia, Kernig’s sign, and Brudzinski’s sign
o Kernig’s sign
Patient supine
Flex hip 90⁰
Straighten leg = pain in hamstring
Bacterial Meningitis: Objective Data o Focal neurological deficits: cranial nerve palsies (CN II – CN VIII), diplopia, seizures,
hemiparesis, and altered mental status o Petechial rash
Occurs 50% of meningococcal cases
Tiny red or purple pinprick rash that progresses to purple blotches, located on trunk, lower extremities, mucous membranes, and conjunctiva
Poor outcome with rapidly evolving rash and requires emergent care
Tumbler test Similar rashes observed in pneumococcal, H influenzae, and enteroviral meningitis
o Nausea, vomiting, chills, malaise, pain in the back, abdomen, and extremities
Bacterial Meningitis: Diagnostics o Medical history and clinical exam o Laboratory studies
Chemistry and coagulation profile, cultures, CSF studies, serology o CT/MRI of the head
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o Lumbar puncture
Contraindications: ICP, CNS mass lesion, focal neurological deficits, papilledema, coagulation disorders, meningococcal septicemia, or septic shock
o Radiography: chest and sinus o EEG
Meningitis o Data assessment—diagnostics
Cultures, cells, glucose protein
Normal CSF Bacterial Viral Fungal
WBC cells/mm
0-5 cells 1000-5000 50-1000 >20
Neutrophils 0% >80% <40% 0
Protein mg/dL 18-45 100-500 <200 >45
Glucose mg/dL 45-80 (0.6xBS) 5-40 (<0.3xBS) >45 <40
Bacterial Meningitis: Patient Problems o Infection of meninges o Elevated body temperature r/t CNS inflammation o Acute pain r/t inflammation of meninges, headache, nuchal rigidity, irritation of pain
receptor, or ICP secondary to CNS inflammation o Seizures: risk for injury r/t seizure activity secondary to cerebral irritation o Increased ICP r/t CNS infection o Hydrocephalus r/t CNS inflammation o Respiratory complications: risk for ineffective respiratory function r/t immobility and pain,
ineffective airway clearance, risk for aspiration r/t seizure activity
Bacterial Meningitis: Infection of Meninges o Characteristics: pain, meningeal irritation, petechial rash o Medical interventions
Antibiotic therapy Strep pneumonia: pen G, ceftriaxone, cefotaxime Resistant to pen—vancomycin Neisseria: pen G or ampicillin H flu: cefotaxime or ceftriaxone
Corticosteroid therapy o Surgical interventions
Treat complications—eg, drainage of CNS abscesses or insertion of ventricular-peritoneal shunt for communicating hydrocephalus
o Nursing interventions
Droplet precautions
Vital signs
Neuro checks
Monitor lab results
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Administer antibiotics, antipyretics, analgesics, and IV fluids
Provide quiet, darkened room and encourage rest
Bed rest, neutral alignment
Promote nutritional intake and fluids
Provide skin care o Expected outcomes
Infectious source identified and infection successfully treated
Return to prior baseline status
No residual neurological deficits
Remains seizure-free o Potential complications
Waterhouse-Friderichsen syndrome
DIC
Sensori-neural hearing or vision loss
Encephalitis or hydrocephalus
Brain abscess or subdural effusions
Increased ICP cerebral herniation death
Permanent neurological deficits
Paralysis; ARDS
Seizures
Bacterial Meningitis: Increased ICP r/t CNS Infections o Characteristics
Change in neurological status
Altered vital signs
Cranial nerve deficits
Headache, nausea, vomiting, dizziness, or nuchal rigidity
Hydrocephalus o Medical interventions
Hyperosmolar diuretics: mannitol
Hypertonic saline
Sedatives: propofol or benzodiazepines
Narcotics: fentanyl or morphine
Fluid administration: crystalloids or colloids o Surgical interventions
Insert ICP monitoring device or external ventricular drain Maintain ICP <15 mm Hg and CPP >60 mm Hg
Perform surgical decompression, excise or drain abscess or lesion to relieve pressure
Ventricular peritoneal shunt placement for hydrocephalus management
Bacterial Meningitis: Increased ICP r/t CNS Infections o Nursing interventions
Monitor neurological status and vital signs
Elevate HOB 30⁰
Suction as needed
Monitor ICP and EVD
Maintain euvolemia, normothermia, and normal electrolyte levels
Administer stool softeners to avoid Valsalva maneuver
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Maintain quiet, darkened room with minimal stimulation o Expected outcomes
ICP remains <15 mm Hg and CPP >60 mmHg or as ordered
Neurological status improves or baseline is maintained
Complications of ICP are resolved
No complications of ICP monitoring develop o Potential complications
Complications of ICP monitoring: fever, infection, seizures, excess fluid volume, herniation, and death
Bacterial Meningitis: Elevated Body Temperature r/t CNS Inflammation o Characteristics
Fever
Warm flushed skin
Diaphoresis
Tachycardia
Tachypnea
Seizures o Medical interventions
Antipyretics
Cooling devices o Nursing interventions
Administer antipyretics as necessary
Administer IV fluids as ordered
Monitor intake and output
Institute cooling measures
Monitor vital signs
Monitor level of consciousness
Monitor lab values: WBC and electrolytes
Bacterial Meningitis: Elevated Body Temperature r/t CNS Inflammation o Expected outcomes
Patient remains afebrile at 37⁰ C
Patient’s BP, RR, and HR are WNL
Patient remains seizure-free o Potential complications
Seizures
Activity intolerance r/t fatigue and malaise secondary to infection
Delayed growth and development r/t brain damage secondary to infectious process, ICP
Disturbed sensory perception: impaired auditory, kinesthetic, visual acuity r/t CNS infection
Bacterial Meningitis: Acute Pain r/t Inflammation of Meninges, Headache, Nuchal Rigidity, Irritation of Pain Receptors, or ICP Secondary to CNS Inflammation o Characteristics
C/o headache, neck and back pain, or nuchal rigidity
Guarding or protective behavior
Withdrawal from social contact
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Facial mask of pain
Moaning, crying, irritability
Increase in vital signs, restlessness o Medical interventions
Analgesic medications as necessary
Supportive therapy o Nursing interventions
Assess location, quality, severity of pain
Assess patient behavior and physiological signs secondary to pain
Provide quiet, darkened room with minimal disturbances
Implement comfort measures to promote relaxation
Institute nonpharmacological measures for pain control
Administer analgesics as prescribed
Assess patient’s pain and effectiveness of interventions and side effects
Administer pain medication prior to activities
Bacterial Meningitis: Acute Pain r/t Inflammation of Meninges, Headache, Nuchal Rigidity, Irritation of Pain Receptors, or ICP Secondary to CNS Inflammation o Expected outcomes
Patient reports adequate pain control
Vital signs are WNL o Potential complications
Risk for injury r/t restlessness and disorientation secondary to pain
Bacterial Meningitis: Seizures Risk for Injury r/t Seizure Activity Secondary to Cerebral Irritation o Characteristics
Loss of consciousness
Incontinence of bowel and bladder
Profuse salivation
Apnea and cyanosis
Respiratory and metabolic acidosis o Medical interventions
Antiepileptic medications
Sedation o Expected outcomes
Patient remains seizure-free
No injuries occur during seizure
No toxic side effects from antiepileptic medications o Nursing interventions
Implement seizure precautions
Protect patient from injury
Document seizure activity
Monitor neurological status and vital signs after seizure
Administer antiepileptic medications as ordered o Potential complications
Status epilepticus
Injury
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Respiratory compromise secondary to ineffective airway clearance
Bacterial Meningitis: Hydrocephalus r/t CNS Inflammation o Characteristics
Headache, N/V
Lethargy
Visual disturbances
Ataxia
Incontinence o Surgical interventions
EVD
Ventricular peritoneal shunt o Nursing interventions
Monitor neurological status and vital signs
Maintain EVD
Provide ventricular shunt post-op care
Monitor for signs of shunt malfunction o Expected outcomes
Hydrocephalus is relieved
Shunt insertion post-op recovery is unremarkable
Shunt functions properly o Potential complications
ICP leading to cerebral herniation and death
Shunt malformation
Viral Meningitis
o Pathophysiology
Viral transmission: fecal–oral contamination or respiratory droplets
Virus replicates at site of entry
Primary viremia is followed by viral replication in blood and spread to CSF
Patient is infectious from 3 days after infection to 10 days after symptoms develop
Incubation period 3–7 days
o Data assessment: Neurologic Exam
Viral
Milder than bacteria
Resembles influenza
Headache, fever, photophobia, malaise, and nausea
Viral Meningitis: Patient Problems o Infection of meninges o Elevated body temperature r/t CNS inflammation o Acute pain r/t CNS inflammation o Hydrocephalus r/t meningitis o GI complications r/t inadequate nutrition o Impaired mobility r/t CNS infection o Psychosocial anxiety r/t CNS infection
Viral Meningitis: Infection of the Meninges o Characteristics
Headache
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Neck pain
Back pain o Medical interventions
Empiric antibiotic therapy initiated until bacterial cultures negative
Acyclovir (Zovirax) used to treat herpes virus types 1 & 3 and varicella-zoster virus
Supportive therapy o Nursing interventions
Same as for bacterial meningitis o Expected outcomes
Patient recovers without neurological sequelae o Potential complications
Encephalitis
Hydrocephalus
Cerebral edema with ICP
Fungal Meningitis o All major fungal agents can produce meningitis o Cryptococcus neoformans most common o High-risk groups include immunocompromised persons, especially with HIV infection o Medical: C neoformans meningitis is treated with amphotericin B and flucytosine o Pathophysiology same as bacterial meningitis
Fungal Meningitis: Assessment o Clinical manifestations
Clinical symptoms often nonspecific but include: Headache Fever Photophobia Malaise Nausea
Different symptoms in patient with and without HIV infection o Diagnostics
Laboratory studies CSF studies Serology (antigen tests)
India ink examination
Latex agglutination tests
ELISA to isolate fungi in CSF CT or MRI
Identify focal lesions; especially in C. neoformans
Fungal Meningitis: Patient Problems o Infection of meninges o Elevated body temperature r/t CNS inflammation o Acute pain r/t CNS inflammation o Hydrocephalus r/t meningitis o GI complications r/t inadequate nutrition o Impaired mobility r/t CNS infection o Psychosocial anxiety r/t CNS infection
Fungal Meningitis: Infection of the Meninges
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o Characteristics
Pain: Headache, neck and back
Fever, malaise, nausea
Lethargy, personality changes
Cranial nerve palsies, papilledema
Meningismus: headache, nuchal rigidity, photophobia, Kernig’s and Brudzinski’s sign o Medical interventions
Antifungal therapy C neoformans treated with amphotericin B and flucytosine
Supportive therapy o Nursing interventions
Same as for bacterial meningitis o Expected outcomes
Infectious source is identified and infection successfully treated
Returns to prior baseline status
Patient does not experience any permanent neurological deficits
Patient remains seizure-free o Patient complications
Encephalitis
Hydrocephalus
Cerebral edema with ICP
Encephalitis o Definition
Inflammation of the brain parenchyma caused by virus, bacterium, fungus, or parasite o Etiology
Virus is most common cause
Respiratory system: mumps, measles, varicella virus
Oral: enteroviruses/polio
Oral or genital: herpes simplex
Bites Animal: rabies Insect: arbovirus (mosquito) Lyme disease (tick)
o Pathophysiology
Arbovirus: includes St. Louis, eastern, western equine and West Nile virus Humans bitten by the vector are asymptomatic or develop vague flu-like symptoms Produces diffuse disintegration of single nerve cells, inflammation, and necrosis of
both white/gray matter (spares the brainstem) o Pathophysiology
Virus Enters body and colonized Penetrates cell Transcribes virus-coated proteins and replicates the viral nucleic acid Blood‒brain barrier prevents virus from entering CNS but can enter through
cerebral capillaries or choroid plexus and/or along peripheral nerves Virus attacks susceptible neurons and causes sell lysis
Encephalitis: Assessment o Subjective data
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Symptoms vary with organism and area involved
Headache is usually present o Objective data
Signs Fever Nuchal rigidity Photophobia Altered LOC Focal neurological deficits Aphasia Badinski’s reflex Involuntary movements Cranial nerve deficits New psychiatric symptoms Cognitive deficits Seizures
Encephalitis: Diagnostics o Medical history and clinical exam o Laboratory studies
Cultures: blood urine, stool, nasopharynx, or sputum
CSF studies Cell count, cytological characteristics, culture Protein level slightly elevated Glucose level normal PCR
Serology: Elisa & Serological assays for antiviral IgM and IgG o EEG o MRI: if not possible, CT of head with and without contrast o Surgery: tissue biopsy in some cases
Encephalitis: Patient Problems o Infection of the CNS o Elevated body temperature r/t CNS inflammation o Acute pain r/t CNS inflammation o Seizures r/t CNS irritation o Increased ICP r/t CNS inflammation o Respiratory complications o Cardiovascular complications o GI complications r/t inadequate nutrition o Impaired mobility r/t CNS infection o Psychosocial anxiety r/t CNS infection
Encephalitis: Herpes Simplex (HSV) o Most common and most severe form
Herpes simplex virus-1 o 2000 cases annually in USA o 30%–70% mortality rate, neurological deficits o HSV accounts for >50% in patients with HIV o No geographical or seasonal pattern
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HSV Encephalitis: Pathophysiology o HSV lies dormant within dorsal ganglia of trigeminal nerve in 90% of people in USA o Virus is activated in trigeminal ganglia and follows fibers and attacks frontal and temporal
lobes, causing bilateral hemorrhagic necrosis
HSV Encephalitis: Assessment o Subjective data
Headache
Confusion
Hallucinations o Objective data
Change in LOC
Personality and behavioral changes
Memory loss
Aphasia
Hemiparesis
Temporal-lobe seizures
Progression to deep coma as cerebral edema increases, herniation may occur leading to death
HSV Encephalitis: Diagnostics o Lumbar puncture
Elevated open pressure
CSF studies: presence of lymphocytes, increased protein level, normal glucose level
PCR: positive for HSV-1 antigen in 98% of cases o EEG
High-voltage, sharp waves in temporal areas
Slow-wave complexes at regular 2- to 3-second intervals o CT
Normal initially
Later scans show gyral enhancement, hypodensity in temporal areas and mass effect in up to 65% of patients
o MRI
PCR: positive for HSV-1 antigen in 98% of cases
Edema and hemorrhage over inferior portion of frontal and temporal lobes
BBB abnormalities seen with contrast o Surgery to obtain cultures of cerebral tissue
HSV Encephalitis: Patient Problems o Infection of brain parenchyma o Acute pain r/t CNS inflammation o Seizures r/t CNS irritation o Increased ICP r/t CNS inflammation o Respiratory complications o Cardiovascular complications o GI complications r/t inadequate nutrition o Impaired mobility r/t CNS infection o Psychosocial anxiety r/t CNS infection
HSV Encephalitis: Infection of the Brain Parenchyma o Characteristics
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Headache, confusion, hallucinations
Change in LOC
Personality changes, behavioral abnormalities
Focal neurological deficits—aphasia, hemiparesis
Temporal lobe seizures o Medical interventions
Acyclovir within 4 days
Supportive care C neoformans treated with amphotericin B and flucytosine
Supportive therapy o Nursing interventions
Same as for bacterial meningitis o Expected outcomes
Infectious source identified and infection successfully treated
Return to prior baseline status
Patient does not experience any permanent neurological deficits
Patient remains seizure-free
Patient does not experience personality/behavioral changes o Potential complications
Moderate to severe neurological deficits in 50% of survivors
Personality/behavioral changes
Seizures and cognitive disability
ICP leading to cerebral herniation
Mortality rate 28% at 18 months after treatment
HSV Encephalitis: Outcomes o Life-threatening illness o Mortality rate of 30%–70% o Increased age and LOC usually predict poor outcomes
Guillain-Barré Syndrome o Definition
Acute, inflammatory, demyelinating polyneuropathy causing weakness, sensory loss, and areflexia
o Etiology
Immune-mediated with precipitating factors of possible infection (viral 1-2 weeks preceding 70% of all cases)
o Pathophysiology
Inflammatory lesions through peripheral nervous system
Defect linked to peripheral nerve myelin
Some cases cause axonal degeneration
Macrophages attack normal myelin, produce demyelination o Subjective data
Rapidly progressing weakness or paresthesias
Usually ascending o Objective data
Progressive motor weakness which ascends
Sensory loss may not be present
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Loss of DTRs
Facial, ocular, or oropharyngeal muscles affected in 50% of cases
Autonomic dysfunction causing ileus, hypotension, hypertension, and arrhythmias
Respiratory compromise if ascends to diaphragm o Diagnostics
LP: increased protein
EMG: slowing of conduction o Management—medical
Plasma exchange urgent every day for 10–15 days
IVIG 1–2 mg/kg in divided doses over 3–5 days Watch for anaphylaxis, chills, fluid overload
Pulmonary—may need to be intubated
Hemodynamic support
Analgesic support for increased pain o Management—nursing
Assess VS/neuro function watching for ascending weakness
Mechanical ventilation—support respiratory function
Watch for hemodynamic alteration Support BP
Assess pain and provide analgesia
Review Questions
Question #10—SP, a 20-year-old college student, presents to the ED with c/o photophobia, stiff neck, temperature of 103⁰, malaise, and purple blotches primarily located on the trunk. He is given antibiotics in the ED. He is admitted to the ICU with a BP of 85/50 mm Hg, HR 140 and ventilated. Cultures have been done but there are no results. SP’s likely infectious illness is: o Lyme disease o Herpes simplex encephalitis o Neisseria meningitides o Guillain-Barré syndrome
Question #10 rationale—SP, a 20-year old college student, presents to the ED with c/o photophobia, stiff neck, temperature of 103⁰, malaise, and purple blotches primarily located on the trunk. He is given antibiotics in the ED. He is admitted to the ICU with a BP of 85/50 mm Hg, HR 140 and ventilated. Cultures have been done but there are no results. SP’s likely infectious illness is: o Lyme disease. Lyme disease is a viral encephalitis that presents with bull’s eye rash and
malaise. It is not accompanied by purple blotches o Herpes simplex encephalitis. The patient may experience headache, fever, malaise but also
has strange behavior, personality changes and seizures o Neisseria meningitides o Guillain-Barré syndrome. Presentation includes ascending weakness accompanied by
sensory loss and cranial nerve dysfunction
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Question #11—Patients sustaining Guillain-Barré syndrome are most likely to have prolonged failure of which organ system? o Cardiac o Respiratory o Renal o Liver
Question #11 rationale—Patients sustaining Guillain-Barré syndrome are most likely to have prolonged failure of which organ system? o Cardiac. Although patients may experience autonomic dysfunction with accompanying BP
variation, arrhythmias, ileus, diaphoresis or loss of sweating, urine retention, it is not chronic heart failure
o Respiratory o Renal. Patients may experience urinary retention but typically do not have acute renal
failure o Liver . The liver is not generally involved
Seizures and Epilepsy Seizures and Epilepsy
o Abnormal firing in the brain o Epileptogenesis occurs during an imbalance between cerebral excitation and inhibition
Brain cells become abnormally linked together, leading to abnormal electrical firing Excitation (glutamate/NMDA) vs inhibition (GABA—facilitates activity of Cl
channels/opens K channels or closes Ca channels) o Classification
Partial seizure: onset of synchronous cortical discharges involving a focal brain region Generalized seizure: sudden onset involving both hemispheres
Seizures and Epilepsy o Partial seizures
Simple partial: focal brain region activity without alteration in consciousness
An aura can be a simple partial seizure
Motor events such as face twitching/hand jerking
Somatosensory events such as unusual taste in mouth
Psychic events—illusions/hallucinations/déjà vu Complex partial seizure: brain region affected with alteration in consciousness
Often preceded by simple partial seizures with progressive impairment in consciousness
Automatisms (lip smacking/blinking/picking at clothes)
Motor phenomena: wandering, running, arm jerking Partial seizure that secondarily generalize
Seizures and Epilepsy o Generalized seizure‒both hemispheres
Absence seizure: impaired responsiveness, minimal motor involvement. Lasts <30 seconds
Myoclonic: sudden shock-like muscle contraction Atonic: drop attacks (brief loss of consciousness/loss of muscle tone) Tonic: increased tone in extensor muscle Clonic: starts with loss of consciousness/sudden hypotonia, then limb jerking
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Tonic-clonic: Loss of consciousness, increased tone, rhythmic muscle jerks
Seizures and Epilepsy o Subjective
Obtain description of event including time Precipitating factors? Post-ictal behavior
o Objective Assess mental state and cognition Evidence of trauma/infection Focal findings Asymmetries
o Diagnostics Lab tests EEG CT/MRI to r/o mass or lesions
Seizures and Epilepsy: Nursing Assessment o History o Type of seizure activity
Absence (petit mal) Focal Tonic-clonic Electrical status Status
Seizures and Epilepsy: Diagnostics o Lab
Electrolytes Hypoglycemia Hypoglycemia Hypoxemia Prolactin level Myoglobin Anticonvulsant drug levels
o EEG
Treatment: pharmacologic Drug Level o Phenobarbital 60-250 mg/day 15-40 mcg/mL o Dilantin (phenytoin) 300-600 mg/day 10-20 mcg/mL o Tegretol (carbamazepine) 600-1200 mg/day 4-12 mcg/mL o Mysoline (primidone) 25 mg tid 5-12 mcg/mL o Depakote (valproic acid) 15-60 mg/kg/day 50-100 mcg/mL o Lamictal (lamotrigine100-300 mg/day 2-4.5 mcg/mL o Neurontin (gabapentin) 900-3600 mg/day 2-20 mcg/mL o Keppra (levetiracetam) 1000-3000mg/day 3-37 mcg/mL o Vimpat (lacosamide) 10-400 mg/day 3.8-9.3 ng/mL
Seizures and Epilepsy o Side-effects profile
Stevens Johnson syndrome: erythema multiforme Aplastic anemia Allergic dermatitis
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Hepatic failure Most common: somnolence, dizziness, memory impairment, cognitive slowing, ataxia
o Nursing interventions Education Explain drug‒drug interactions Other: ketogenic diet (high- fat/low-carb/restrict calories); vagal nerve stimulator;
surgery (temporal lobectomy or corpus callosotomy)
Status Epilepticus
Pathophysiology o Tonic –clonic seizures o Increase cerebral metabolic rate/oxygen use o CBF increases 3–5x normal o Cellular swelling o Systemic metabolic acidosis
Etiology/Precipitating Factors o Withdrawal from anticonvulsants, alcohol, or drugs o CNS infections o Brain tumors o Metabolic disorders—uremia, hypoglycemia, or hyponatremia o Craniocerebral trauma o Cerebral edema o Stroke
Interventions o Airway and ventilation
Supplemental oxygen and pulse oximetry Intubate if prolonged seizure Check blood glucose
o Normal saline IV Thiamine 100 mg diluted with 8 mL NS slow IV push over 5 minutes then 50% dextrose 50 mL slow IV push (if bedside, glucose <70 mg dL)
o Stop seizure Lorazepam 2 mg IV push every 1 minute up to 8 mg Fosphenytoin (Cerebyx) 20 (phenytoin equivalents [PE]) mg/kg
o Protect from injury
Interventions o If still seizing
Give fosphenytoin 5 PE mg/kg IV; may repeat with another dose to a loading dose of 30 PE mg/kg
Phenobarbital 20 mg/kg IV—infuse at 50–100 mg/min; may repeat with additional 5–10 mg/kg to a total dose of 30 mg/kg (must be intubated and mechanically ventilated)
Lorazepam 2 mg/kg V push every 1 minute until a 20 mg total loading dose is given o Additional antiepileptic drug
Valproate sodium (Depacon) 25 mg/kg IVPB loading dose over 60 min x 1 and maintenance 10–15 mg/kg/day every 6 hours
Propofol 1–2 mg/kg x 1 IV (administered by MD), then drip 20–250 mcg/kg/min (must be intubated and mechanically ventilated)
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Pentobarbital 5–15 mg/kg IV x 1 over one hour, then 0.5–3 mg/kg/hr (must be intubated and mechanically ventilated)
Midazolam 10 mg IVP x 1, then 0.05–0.4 mg/kg/hr Diazepam 0.15 mg/kg up to 10 mg IV push at 5 mg/min Lorazepam 2 mg IV push every 2 hours
o No paralytics unless continuous EEG in place
Review Questions Question #12—A 10-year old male ignores repeated requests to answer questions and often
stares for short periods of time, as reported by his teacher. This type of seizure is a: o Partial seizure o Complex partial seizure o Myoclonic seizure o Generalized seizure known as an absence seizure
Question #12 rationale— A 10-year old male ignores repeated requests to answer questions and often stares for short periods of time, as reported by his teacher. This type of seizure is a: o Partial seizure. Partial seizures are localized to one area of the brain and do not impair
consciousness o Complex partial seizure. These are manifested by automatisms and motor phenomena such
as wandering, running, or arm jerking o Myoclonic seizure. These are generalized seizures that are sudden shock-like muscle
contractions o Generalized seizure known as an absence seizure
Question #13—A patient in status epilepticus must receive medication immediately to halt the seizure activity. The first-line medication for status epilepticus is: o Diazepam 10 mg PO o Midazolam 1 mg IV o Phenobarbital 30 mg IV o Lorazepam 2 mg IV
Question #13 rationale—A patient in status epilepticus must receive medication immediately to halt the seizure activity. The first line medication for status epilepticus is: o Diazepam 10 mg PO. A patient in status epilepticus will be unable to take any medication by
mouth o Midazolam 1 mg IV. Although midazolam is used as a secondary drug in status epilepticus,
the dose would be much higher, ie, 10 mg o Phenobarbital 30 mg IV. The drug is considered a second-line drug and the dosing is 20
mg/kg IV given slowly 50–100 mg/min o Lorazepam 2 mg IV
Brain Tumors
Facts/Stats o Incidence
Primary—36,000/year Secondary—18,000/year
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o Males >females o Age: 40–60 age group o Classification
Benign: regular cell structure Malignant: infiltrates brain tissue, poor boundaries, rapid mitotic activity, necrosis Location: supra vs infratentorial Primary vs secondary Intra-axial (glial cells) vs extra-axial (meninges, CN, pituitary, and cysts) Histological origin
Intrinsic Tumors o Astrocytoma and GBM
Grade I‒IV o Oligodendrocytoma
White matter Frontal and parietal lobes
o Ependymoma Ependymal cells in ventricles
o Medulloblastoma Highly malignant in young children
Extrinsic Tumors o Meningiomas
Benign, slow growing o Neuromas
Acoustic tumor (CN VIII) Schwannoma
o Neurofibromatosis Type I: café au lait spots Type II: bilateral hearing loss
Congenital Tumors o Hemangioblastoma
Slow growing, vascular tumor Common in cerebellum
o Craniopharyngioma Embryonic Rathke’s pouch/suprasellar Arise from pituitary hypophysis
ICP, pituitary/hypothalamic dysfunction
Visual disturbances
Pituitary Tumors o Secreting
ACTH (Cushing) or GH (gigantism) o Non-secreting (90% space occupying)
Compresses pituitary: visual/hypopituitary
Pathophysiology o Increased ICP o Tumor growth o Cerebral edema
Tissue surrounding the vicinity of tumor
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Endothelial cells of white matter Increase permeability of plasma and vasogenic edema
Signs/Symptoms o Headache o Seizure o Vomiting o Alterations in consciousness o Localizing signs
Signs/Symptoms o Tumor area
Frontal: affect, motor, speech, behavior Parietal: numbness, sensory Temporal: psychomotor seizures/receptive aphasia Occipital: vision Pituitary: visual, headaches, Cushing, acromegaly Ventricles: hydrocephalus, headache, changes in LOC Cerebellum: ataxia, incoordination, dysmetria Brainstem: CN defects, vomiting, respiratory
Complications of Tumor Growth o Edema o Increased ICP o Seizures o Hydrocephalus o Hormonal changes o Focal deficits
Treatment o Stereotactic therapy o Craniotomy o Gamma knife o Conventional radiation o Brachytherapy o Chemotherapy o Gene therapy/virus therapy
Nursing Interventions o Pre-op: steroids, anticonvulsants, body image o Post-op:
ABC Monitor neurologic status Watch for seizures
Phenytoin: dosing/levels System support Family/patient support
o Pituitary tumors Watch I/O, Na+, specific gravity
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Review Questions Question #14—HH, a 45-year-old right-handed male, presents to the ED with headache, right
arm weakness with right facial droop and difficulty expressing speech. A CT scan reveals diffuse cerebral edema surrounded by a ring-enhancing lesion. The most likely location of the mass is: o Right parietal lobe of cerebral hemisphere o Left temporal lobe of cerebral hemisphere o Right frontal lobe of cerebral hemisphere o Left frontal lobe of cerebral hemisphere
Question #14 rationale—HH, a 45-year-old right-handed male, presents to the ED with headache, right arm weakness with right facial droop and difficulty expressing speech. A CT scan reveals diffuse cerebral edema surrounded by a ring-enhancing lesion. The most likely location of the mass is: o Right parietal lobe of cerebral hemisphere. The right parietal lobe’s main function is sensory
perception, body awareness, and sensory interpretation of input affecting the left side of the body
o Left temporal lobe of cerebral hemisphere. The left temporal lobe’s main function is interpretation of hearing, auditory perception, short-term memory and comprehension of the spoken word
o Right frontal lobe of cerebral hemisphere. The right frontal lobe is responsible for higher mental functions and movement to the left arm/leg/face. The right frontal lobe in right-handed individuals is considered to be the non-dominant hemisphere. Expressing speech is located in the dominant hemisphere in the frontal lobe
o Left frontal lobe of cerebral hemisphere
Question #15 —TP, a 53-year-old male, has been diagnosed with a brain mass. His symptoms include: contralateral sensory loss, neglect to the left side, and inability to draw with loss of spatial orientation. The most likely area of the brain affected is: o Parietal lobe o Frontal lobe o Temporal lobe o Occipital lobe
Question #15 rationale—TP, a 53-year-old male, has been diagnosed with a brain mass. His symptoms include: contralateral sensory loss, neglect to the left side, and inability to draw with loss of spatial orientation. The most likely area of the brain affected is: o Parietal lobe o Frontal lobe. Tumors in this area affect motor to the opposite side, speech (if dominant
hemisphere), judgment, personality, initiation, and continence o Temporal lobe. Tumors in this area present with receptive aphasia (dominant hemisphere
only) and some visual field cuts o Occipital lobe. Tumors in this area affect visual perception and field of vision
Question #16 —TP undergoes a craniotomy for debulking of a large tumor. Postoperatively, he is extubated and admitted to the ICU. After 1 hour, TP sustains a generalized seizure lasting 45 seconds. What is your initial intervention? o Check the pupillary reaction o Administer IV midazolam
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o Assess airway and breathing and prepare for possible intubation o Get a stat CT of the brain
Question #16 rationale—TP undergoes a craniotomy for debulking of a large tumor. Postoperatively, he is extubated and admitted to the ICU. After 1 hour, TP sustains a generalized seizure lasting 45 seconds. What is your initial intervention? o Check the pupillary reaction. Although the pupils need to be checked, it would not precede
assessing the airway o Administer IV midazolam. Airway stabilization is first. Lorazepam IV would be the
preferential medication of choice to reduce recurrence o Assess airway and breathing and prepare for possible intubation o Get a stat CT of the brain. This intervention would be done after the other three
interventions
Chronic Neurologic Disorders Parkinson’s Disease
o Neurodegenerative disorder caused by: Depletion of dopamine producing cells in substantia nigra Average onset is age 60, higher in men /Caucasian
o Cardinal signs o Resting tremor, rigidity, bradykinesia, and diminished postural stability
o Other Increased risk of falls Can have depression/dementia/anxiety/psychosis Other: apathy, sleep disturbances, impulse control disorders Autonomic dysfunction: urinary incontinence, sexual dysfunction, constipation,
orthostatic hypotension, impaired thermoregulation, sensory abnormalities Dysphagia/excessive drooling
Parkinson’s Treatment o Pharmacologic
L-dopa: Carbidopa plus L-dopa (Sinemet) Dopamine agonists: 1st line tx Amantadine (Symmetrel): tx dyskinesias Catechol-O-methyl transferase (COMT) inhibitors: used adjunctively to ldopa to prevent
breakdown of dopamine and prolong availability of L-dopa o Surgical interventions
Deep brain stimulation: target subthalamic nucleus or globus pallidus interna
Permits return of normal or near normal downstream outputs, allowing normalization of motor and/or limbic function
Deep brain stimulation: post op
Observe for changes in neuro exam
Keep systolic BP < 150 mm hg for first 24 hours
IV antibiotics 24-48 hours
Stool softeners / anti-embolic devices
Deep breathing/coughing to reduce pneumonia Device turned on 2-3 weeks after placed
Myasthenia Gravis
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o Description: autoimmunie disorder in which normal transmission of nerve impulses are interrupted at the neuromuscular junction. Affects voluntary muscle groups including ocular, oropharyngeal, facial, shoulders, and
arms/legs
Proximal > distal
Characterized by fluctuating and fatigable muscle weakness exacerbated by exercise and improves with rest
o Affects women > men; usually 20s and 30s o Etiology
Acquired autoimmune process related to receptors for acetylcholine at muscle surface reduced by auto-antibodies leads to impaired neuromuscular transmission and weakness.
Thymus abnormalities may be responsible for causing immune attack on the muscle receptors
o Initial manifestations:. Ptosis/diplopia 80% of cases Oropharyngeal weakness – painless/fatigable dysphagia or dysphonia Fatigable limb weakness during course of day Fluctuate over time; worsens after sustained activity Exacerbation r/t systemic illness, fever, surgery, menses, pregnancy, hypothyroidism,
heat, or stress o Signs and symptoms
Subjective
Muscle weakness
Diplopia/ptosis
Slurred speech
Dysphagia
Shortness of breath Objective
Weakness – more proximal
May have inability to lay flat – orthopnea
Frequent yawning, sighing
Difficulty swallowing o EMG o Edrophonium chloride (Bioniche test): short acting antichoinesterase inhibitor
Requires IV administration 2 mg/ test for strength 45-60 seconds later. Can repeat up to 10 mg
Positive if improvement in strength seen (effect disappears in 5 minutes) Use with caution: bradycardia/asystole, excessive salivation, bronchial secretions
o Treatment Administration of anticholiesterase inhibitors
Prevents rapid destruction of Ach
Pyridostigmine (Mestinon) must be given on time with no missed dose
Corticosteroids/immunosuppressive agents
Cyclosporine (Neoral): inhibits t-cell immune responses
Plasma exchange
IVIG: temporary intervention
Neurologic System
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Mycophenolate mofetil (CellCept): immunosuppressive agent reduces the production of antibodies by attacking the receptor sites of neuromuscular junction
Surgical intervention: thymectomy
Nursing: administer drugs on time, patient education