Nervous System and Neurologic Assessment

Nervous System Overview

• The central nervous system (CNS) consists of the brain and spinal cord.
• The peripheral nervous system (PNS) includes cranial and spinal nerves.
• The autonomic nervous system (ANS) has two divisions: sympathetic ("fight or flight") and parasympathetic ("rest and digest").

Neurologic Assessment Components

• Level of Consciousness (LOC) is the most sensitive indicator of neurologic status.
• Assess a patient's orientation to person, place, and time to determine LOC.
• The Glasgow Coma Scale (GCS) assesses eye-opening (4), verbal response (5), and motor response (6).
• A GCS score of ≤8 indicates a coma.
• Motor function assessment involves strength, tone, and coordination.
• Assess for drift, pronator drift, and posturing when evaluating motor function.
• Sensory assessment includes light touch, pain, temperature, vibration, and proprioception.
• Pupil assessment includes size, shape, and reactivity (PERRLA: Pupils Equal, Round, Reactive to Light and Accommodation).
• Reflex assessments include deep tendon reflexes (biceps, triceps, patellar).
• The Babinski sign is abnormal in adults and indicates an upper motor neuron lesion.

Diagnostics

• CT and MRI scans are used to evaluate the structure of the nervous system.
• EEG measures electrical activity in the brain.
• Lumbar puncture is performed for CSF analysis.
• Cerebral angiography provides vascular imaging of the brain.

Red Flags

• Sudden change in LOC requires immediate attention.
• Unequal pupils can indicate a neurological issue.
• New weakness or slurred speech are concerning signs.
• Cushing’s triad (increased SBP, decreased HR, irregular respirations) is a late sign of increased ICP.

Key Conditions of the Central Nervous System

• Stroke (CVA) can be ischemic (clot) or hemorrhagic (bleeding).
• Signs and symptoms of stroke can be remembered with the acronym FAST (Face, Arm, Speech, Time).
• Treatment for ischemic stroke includes tPA, while management for both types includes BP control and rehab.
• Seizures/Epilepsy include types such as tonic-clonic, absence, and focal.
• Safety measures during a seizure include placing the patient in a side-lying position, clearing the area, and not restraining the patient.
• Treatment for seizures includes antiepileptic medications like phenytoin and levetiracetam.
• Multiple Sclerosis (MS) is an autoimmune demyelination of the CNS.
• Symptoms of MS include fatigue, vision changes, and weakness.
• Treatment for MS includes steroids and immunomodulators.
• Parkinson's Disease results from decreased dopamine levels.
• Symptoms of Parkinson's Disease include tremor, rigidity, bradykinesia, and postural instability.
• Levodopa-carbidopa is used in the treatment of Parkinson's Disease.
• Meningitis is the inflammation of the meninges.
• Symptoms of meningitis include fever, neck stiffness, photophobia, and positive Kernig’s/Brudzinski’s signs.
• Treatment for meningitis includes IV antibiotics and droplet precautions.
• Encephalitis involves brain tissue inflammation, often viral.
• Symptoms of encephalitis include fever, confusion, and seizures.
• Treatment for encephalitis includes antivirals and supportive care.
• Alzheimer's Disease is a progressive memory/cognitive decline condition.
• Treatment for Alzheimer's Disease focuses on safety, structure, and medications for memory support.

Types of Spinal Cord Injury (SCI)

• Primary SCI results from direct trauma.
• Secondary SCI is caused by ischemia, swelling, and inflammation after the initial insult.

Classification of Spinal Cord Injury

• Complete SCI involves total loss of function below the injury site.
• Incomplete SCI involves partial motor/sensory function being preserved.

Spinal Shock vs. Neurogenic Shock

• Spinal shock results from sudden loss of reflexes and is temporary, while neurogenic shock results from loss of sympathetic tone and is ongoing.
• Spinal shock presents with normal or decreased BP, while neurogenic shock has significantly decreased BP.
• Spinal shock typically presents with a normal HR, while neurogenic shock presents with bradycardia.
• Reflexes are absent in spinal shock but may be present in neurogenic shock.

Autonomic Dysreflexia

• Autonomic dysreflexia is seen in injuries T6 and above.
• It's triggered by stimuli such as a full bladder or tight clothing.
• Autonomic dysreflexia presents with severe HTN and bradycardia.
• Other symptoms of autonomic dysreflexia include flushed face and sweating above the injury, and pale, cool skin below the injury.
• Interventions include sitting the patient up, removing the stimulus, and notifying the provider.

Labs and Risks

• Monitor for hyponatremia/SIADH or hypernatremia/DI in SCI patients.
• ABG changes from impaired ventilation, especially with cervical injuries.

Nursing Interventions

• Immobilize the spine using log rolling and a cervical collar.
• Maintain the patient's airway, especially in C1–C5 injuries.
• Prevent skin breakdown, contractures, and DVT.
• Implement bowel/bladder programs for neurogenic bladder management.

Key Neurologic Emergencies

• Status Epilepticus
• Increased Intracranial Pressure (ICP)
• Traumatic Brain Injury (TBI)
• Brain Herniation
• Subdural & Epidural Hematomas
• Concussions & Contusions
• Brain Death Criteria
• Emergency Neuro Assessments

Status Epilepticus

• Status epilepticus is defined as a seizure lasting >5 minutes or repeated seizures without regaining consciousness.
• Causes include epilepsy, sudden medication withdrawal, brain injury, and metabolic imbalance.
• Symptoms include continuous convulsions, unresponsiveness, and hypoxia.
• First-line management includes IV lorazepam or diazepam.
• Second-line treatments include phenytoin (Dilantin) and levetiracetam (Keppra).
• Maintain airway, suction, and monitor O₂ and glucose levels.

Increased Intracranial Pressure (ICP)

• Normal ICP ranges from 5–15 mmHg.
• Causes of increased ICP include bleed, tumor, swelling, and infection.
• Early signs include decreased LOC (most sensitive sign), headache, N/V, and sluggish pupils.
• Late signs include Cushing’s Triad (increased SBP, decreased HR, irregular respirations), fixed/dilated pupils, posturing, and coma.
• Management includes elevating the HOB to 30° and keeping the neck neutral.
• Medications used include Mannitol and hypertonic saline.
• Maintain PaCO₂ between 30–35 mmHg.
• Prevent fever, seizures, and straining.

Traumatic Brain Injury (TBI)

• GCS scores for TBI: Mild (13–15), Moderate (9–12), Severe (≤8).
• Types of TBI include:
  • Concussion: Brief LOC, confusion, headache
  • Contusion: Brain bruise, longer LOC
  • Diffuse Axonal Injury: Widespread brain injury leading to coma
  • Hematomas: Epidural (arterial bleed with lucid interval then deterioration), Subdural (venous bleed with slower onset), Intracerebral (bleeding into brain tissue)

Brain Herniation

• Brain herniation is caused by increased ICP, causing brain tissue to shift through the foramen magnum.
• Symptoms include rapid LOC decline, dilated pupils, posturing, and apnea.
• Emergency interventions include surgery (e.g., decompressive craniectomy) and urgent ICP control.

Neuro Assessment & Diagnostics

• Glasgow Coma Scale (GCS): Eye (4), Verbal (5), Motor (6)
• Assess pupils for size, symmetry, and reaction.
• Perform motor/sensory checks.
• Non-contrast CT scan is the first-line diagnostic for suspected bleed.
• Monitor ABG and electrolytes for causes of neuro change (e.g., hypoxia, hyponatremia).
• EEG is used to evaluate seizure activity.
• ICP Monitoring: Invasive in ICU setting

Brain Death Criteria

• GCS = 3 (no motor/verbal/eye response)
• Absence of pupillary light reflex, corneal/gag reflex, and spontaneous respirations (confirmed with apnea test).
• Confirmation requires neurologist assessment and diagnostics (e.g., EEG, cerebral blood flow study).

Nursing Priorities for Neurologic Emergencies

• Maintain airway (ABCs first!).
• Frequent neuro checks (q1h or more).
• Implement seizure precautions.
• Prevent increased ICP: elevate HOB, avoid coughing/straining.
• Monitor for signs of herniation or decline.
• Prepare for potential intubation or surgical intervention.

Quick Memory Aids

• Cushing’s Triad = Late ICP Signs: Cheyne-Stokes/irregular respirations, Unusual BP (widened pulse pressure), Slow heart rate (bradycardia).
• Seizure Management = “AIR”: Airway, IV Benzos, Recover & Reassess.
• Brain Herniation = BAD: Bradycardia, Apnea/irregular respirations, Dilated pupils, ↓ LOC.

Eye Anatomy & Physiology Review

• Cornea: Clear front layer that refracts light.
• Lens: Focuses light onto the retina.
• Retina: Contains rods and cones; sends signals to the brain via the optic nerve.
• Macula: Center of the retina; responsible for sharp vision.
• Aqueous humor: Fluid in the anterior chamber; drains via the trabecular meshwork.
• Vitreous humor: Gel-like substance in the posterior chamber.

Common Eye Conditions

• Cataracts: Clouding of the lens.

Cataracts

• Causes: Age, diabetes, smoking, corticosteroids, UV light.
• Symptoms: Painless, blurry vision, glare sensitivity, reduced night vision.
• Treatment: Surgical lens replacement.
• Post-op teaching: Avoid heavy lifting, bending, straining, wear eye shield at night, and report sudden pain, floaters, or flashes.

Glaucoma

• Increased intraocular pressure (IOP) leading to optic nerve damage.
• Types: Primary open-angle (chronic gradual peripheral vision loss), acute angle-closure (sudden severe pain, halos, nausea, emergency!).
• Diagnosis: Tonometry (measures IOP), visual field testing.
• Medications: Timolol (beta blocker, decreases aqueous humor production), Latanoprost (prostaglandin, increases outflow).
• Surgery: Trabeculoplasty or iridotomy (for angle-closure).

Macular Degeneration

• Dry (non-exudative): Most common, gradual central vision loss.
• Wet (exudative): Rapid onset, new vessel growth causes bleeding.
• Symptoms: Blurred central vision, difficulty reading, distorted lines.
• Treatment: No cure for dry; anti-VEGF injections for wet type.

Retinal Detachment

• Separation of the retina from underlying tissue.
• Symptoms: Flashing lights, floaters, and a "curtain" over vision.
• Considered an emergency that can lead to blindness if untreated.
• Surgery: Scleral buckle, pneumatic retinopexy.
• Post-op: Positioning is crucial (face down or side), avoid air travel until cleared.

Diabetic Retinopathy

• Microvascular damage to the retina from uncontrolled diabetes.
• Symptoms: Blurred vision, floaters, and vision loss.
• Management: Tight glucose control, laser photocoagulation, and anti-VEGF therapy.

Refractive Errors

• Myopia (nearsighted): See close, blurry far.
• Hyperopia (farsighted): See far, blurry close.
• Astigmatism: Uneven curvature of the cornea.
• Presbyopia: Age-related loss of near vision.

Nursing Assessment of the Eye

• Visual acuity: Snellen chart.
• PERRLA: Pupils Equal, Round, Reactive to Light and Accommodation.
• Tonometry: Measures IOP.
• Ophthalmoscope: Inspects the retina and optic disc.
• Slit-lamp exam: Detailed front-eye evaluation.
• History: Blurred vision, pain, discharge, trauma, medical history (DM, HTN).

Red Flags / Urgent Signs

• Sudden vision loss or changes.
• Eye pain with nausea/headache (acute angle-closure glaucoma).
• Flashing lights, floaters, and shadow (retinal detachment).
• Eye trauma or foreign body.
• Post-op signs: increased pain, bleeding, purulent drainage require immediate reporting.

Quick Memory Aids

• Cataracts = Cloudy lens, slow & painless
• Glaucoma = Pressure, peripheral loss (tunnel vision)
• Macular degeneration = Middle vision loss
• Retinal detachment = Curtain down, flashing lights
• Acute angle-closure = ER-level pain + halos + nausea

Ear Anatomy Review

• External Ear: Pinna, auditory canal collects sound.
• Middle Ear: Tympanic membrane (eardrum), ossicles transmits sound.
• Inner Ear: Cochlea (hearing), vestibule & semicircular canals (balance).
• Cranial Nerve VIII: Vestibulocochlear hearing + balance.

Assessment of the Ear & Hearing

• Subjective Data: Hearing difficulty or loss (onset, progression), Tinnitus (ringing), vertigo, fullness, Otalgia (ear pain), drainage, itching, History of infections, noise exposure, ototoxic medications
• Objective Assessment: Inspection: External ear alignment, size, shape, skin; Otoscopy: Visualize canal and tympanic membrane
• Hearing Tests: Whisper test – screens for hearing loss; Weber test – lateralization (conductive loss = sound louder in affected ear); Rinne test – air vs. bone conduction (AC > BC = normal); Audiometry – gold standard

Common Conditions & Concepts of Care

• Presbycusis: Age-related sensorineural loss; Gradual, bilateral high-frequency loss; Intervention: Hearing aids, communication strategies
• Ototoxicity: Damage to inner ear due to meds (e.g., aminoglycosides, furosemide, cisplatin); Monitor for: Tinnitus, balance issues, hearing changes; Nursing Action: Notify provider, stop or adjust dose
• Otitis Externa ("Swimmer’s Ear"): Infection of external canal; Pain with pinna movement, discharge, redness; Care: Topical antibiotics, ear drops, keep dry
• Otitis Media: Middle ear infection, often follows URI; Bulging, red tympanic membrane; Treatment: Antibiotics, myringotomy for recurrent cases
• Tinnitus: Perception of sound without external stimulus; Causes: Noise trauma, aging, ototoxic drugs; Often co-occurs with hearing loss; Management: Hearing aids, stress reduction, masking
• Meniere’s Disease: Excess inner ear fluid resulting in balance and hearing problems; Triad: Vertigo, tinnitus, sensorineural hearing loss; Management: Low-sodium diet, fluid restriction; Diuretics, anti-nausea meds; Safety: Prevent falls during vertigo attacks; Surgical options if severe

Interventions & Hearing Devices

• Hearing Aids: Amplify sound for sensorineural loss; Teach: daily cleaning, proper insertion, battery use
• Cochlear Implants: For profound sensorineural loss; Surgically implanted device stimulates the auditory nerve
• Communication Techniques: Face patient, speak slowly and clearly; Reduce background noise; Use written communication or gestures if needed

Nursing Diagnoses and Priorities

• Impaired verbal communication
• Disturbed sensory perception (auditory)
• Risk for falls or injury (esp. with vertigo/Meniere’s)
• Social isolation or anxiety related to hearing loss

Safety & Red Flags

• Sudden hearing loss requires urgent referral.
• Vertigo with vomiting/falls indicates risk of injury.
• Tinnitus worsening with ototoxic meds should be reported immediately.
• Post-op ear surgery (e.g., tympanoplasty) requires avoiding sneezing/blowing nose.

Memory Tips

• Meniere’s = “Mind spinning” vertigo, tinnitus, hearing loss.
• Ototoxic drugs = “GAF”: Gentamicin, ASA, Furosemide.
• Conductive loss = canal/tympanic issue.
• Sensorineural = cochlea/nerve issue.

Eye Disorders

• Conjunctivitis ("Pink Eye"): Cause: Bacterial, viral, or allergic; S/S: Redness, itching, discharge (purulent in bacterial); Nursing Care: Hand hygiene; Don’t share towels; Warm compress (bacterial), cool compress (allergic)
• Strabismus: Misalignment of the eyes (crossed eyes); Tx: Patch the stronger eye to strengthen the weaker eye, surgery if needed
• Amblyopia ("Lazy Eye"): Reduced vision in one eye due to poor development; Often secondary to strabismus; Tx: Eye patching, corrective lenses, early intervention critical
• Cataracts (Pediatric): Clouding of the lens; may be congenital or acquired; S/S: Absent red reflex, white pupil (leukocoria); Tx: Surgical removal + corrective lenses
• Retinoblastoma: Malignant tumor of the retina