Neuro Disorders, Injuries & Care – Comprehensive Study Notes

Nervous System Architecture

• Core divisions
• Central Nervous System (CNS) – brain + spinal cord.
• Peripheral Nervous System (PNS)
• 31 pairs of spinal nerves distributed 8 C, 12 T, 5 L, 5 S, 1 Co.
• 12 cranial nerves.
• Autonomic Nervous System (ANS)
• Sympathetic – “fight-or-flight”: ↑HR, ↑BP, pupil dilation, shunts blood from GI.
• Parasympathetic – “rest-and-digest”: energy conservation, ↑GI motility.

Headaches

• Origin structures – muscle fibers, meninges, facial & vascular structures, cranial/spinal nerves.
• Highly variable in intensity, duration, frequency, location.
• Classification
• Primary (headache is the disorder): migraine, cluster, tension-type.
• Secondary (symptom of other pathology): trauma, infection, ↑ICP, psychiatric, etc.
• Etiologic clues
• Tension – stress, poor posture, depression.
• Cluster – stress, allergens, toxins, meds, tobacco/ETOH.
• Migraine – genetic, trauma, foods/additives, environment; leading cause of disability in women <50 yr.
• Systemic effects – nausea, visual changes, ↑BP, anorexia, fatigue, GI upset, anxiety/depression.
• Phenotypes
• Tension – mild–moderate, bilateral “band-like”, cervical/shoulder/back tightness.
• Cluster – severe unilateral (retro-orbital) pain, lacrimation, nasal congestion, eyelid/facial edema or ptosis.
• Migraine (four phases)
1. Prodrome (hrs–days): mood change, cravings, yawning.
2. Aura: visual scintillations/smells/pins & needles – a signal, not the trigger.
3. Headache: throbbing ± photo/phonophobia.
4. Post-drome: “hangover” – fatigue, cognitive fog.
• Nursing priorities – dark quiet room, ensure safety, med education, trigger diary.
• Diagnostics – CMP, thyroid panel, CT/MRI if secondary suspected.

Glasgow Coma Scale (GCS)

• Eye 4, Verbal 5, Motor 6 ⇒ max 15.
• 13–15 = mild TBI.
• 9–12 = moderate.
• <9 = severe.
• Trend serial scores to detect neurologic decline.

Seizures & Epilepsy

• Definition – abnormal, unregulated neuronal discharges; chronic recurrence = epilepsy.
• Etiologies – structural (AVM), genetic, infectious (most common), metabolic (e.g., glucose <20\text{ mg·dL}^{-1}), immune, idiopathic.
• Health impact – driving limits, psychosocial isolation, cardio-pulmonary stress.
• Temporal stages
• Prodromal (hrs–days).
• Aura (early ictal) – individualized sensory cue (odor/halo/taste).
• Ictal – active seizure; TIME IT.
• Post-ictal – 5–30 min to baseline: fatigue, N/V, confusion.
• Onset categories
• Focal – one hemisphere; awareness retained/impaired; motor (automatisms) or non-motor.
• Generalized – both hemispheres; LOC.
• Motor: tonic-clonic, clonic, tonic, myoclonic, atonic.
• Non-motor: absence.
• Signature types
• Tonic-clonic – LOC → tonic stiffening → clonic jerks; post-ictal confusion + HA.
• Atonic – sudden loss of tone → falls (teach helmet).
• Myoclonic – brief symmetric jerks with retained awareness.
• Absence – abrupt staring, ± automatisms.

Status Epilepticus

• Emergency: continuous seizure ≥5 min OR ≥2 seizures without return to baseline.
• Diagnostics – MRI/CT (structural), EEG (confirm), LP (infection), tox screen, CBC/glucose.
• Precautions/first aid – lower to floor, remove hazards, loosen clothing, left-lateral, nothing in mouth, protect airway, pad rails.

Cerebrovascular Events

Transient Ischemic Attack (TIA)

• “Mini-stroke”: transient neuro deficit from arterial stenosis/occlusion; complete symptom resolution.
• Prognosis – ~30\% will have stroke within 1 yr if untreated; >50\% of those strokes occur ≤48 h; highest risk in age ≥65.
• FAST screen – Face droop, Arm weakness, Speech slurred, Time → EMS.
• Work-up – non-contrast CT ≤1 h, MRI, ECG (A-fib/flutter), labs.
• Tx – antiplatelets, risk-factor modification, possible carotid endarterectomy if stenosis.

Stroke

• Persistent neuro deficit.
• Ischemic – thrombotic/embolic.
• Hemorrhagic – vessel rupture; hallmark abrupt “worst HA of life”.
• Shared risk factors – HTN, DM, sleep apnea, valvular dz, MI, aneurysm.
• Older adults – ~50\% of survivors have ↓mobility.
• Imaging identical to TIA; rule-out hemorrhage before thrombolytics.

Cerebral Edema / ↑ICP

• Causes – trauma, stroke, tumors, hydrocephalus.
• S/S – HA, confusion, visual change, seizures, N/V, fatigue, incontinence.
• ICU – ICP bolt, CT/MRI, LP (infection).
• Nursing – HOB 30–45^{\circ}, neck midline, low-stim environment, seizure pads, possible sedation.

Traumatic Brain Injury (TBI)

• Spectrum – concussion (mild) → diffuse axonal injury (DAI) → subdural, subarachnoid/epidural bleeds.
• Primary injury at impact; secondary cascade (edema, vasospasm, ischemia) days later.
• DAI – rotational force → brainstem shearing → prolonged coma.
• Concussion S/S – HA, N/V, dizziness, concentration issues, amnesia (can persist months).
• Subdural hematoma – blood between dura & brain; acute (emergent) vs chronic (slow).
• Mechanisms – blunt (most common), penetration (most fatal), blast.
• Older adults – dementia may mask decline; GCS less reliable.
• Biomarker research – serum proteins detectable within hrs of TBI.

Spinal Cord Injury (SCI)

• Pathoanatomy
• Distraction (stretch) vs transection.
• Complete vs incomplete – total absence vs partial preservation below lesion.
• Tetraplegia: \text{C1–T1}. Paraplegia: \text{T2–S5}.
• Prognostic timeline – neuro status declared within 72 h; major recovery in 3 mo, plateau ≈9 mo.
• Level-specific
• \text{C4} ↑ – loss all extremity movement; ventilator risk.
• \text{C5+} – sip-and-puff wheelchair.
• \text{C6} – some wrist control; drive adapted chair.
• \text{T1} – full arm/hand; trunk/leg limits.
• Complications
• Spinal shock – immediate flaccidity, areflexia, bowel/bladder loss (transient).
• Autonomic dysreflexia (lesion ≥\text{T6}) – noxious stimulus → unchecked sympathetic surge → severe HTN, HA, bradycardia.
• Neurogenic shock – hypotension + bradycardia + hypothermia.
• VTE, pneumonia, heterotopic ossification.
• Management – ABCs, hemodynamic stability, halo fixation (keep wrench), decompression/fusion surgery, bowel program (↑fiber/fluids), intermittent cath.
• Meds – NSAIDs, anticonvulsants (neuropathic pain), antidepressants (e.g., duloxetine), opioids, antispasmodics.

Parkinson’s Disease (PD)

• Degeneration of substantia nigra → ↓dopamine & norepinephrine.
• Motor triad – resting tremor, bradykinesia, rigidity; + postural instability.
• Non-motor – fatigue, orthostatic hypotension, constipation.
• Lewy bodies – intraneuronal inclusions (diagnostic hallmark).
• Stage progression

1. Unilateral mild tremor; ADLs intact.

2. Bilateral symptoms, posture change, ADLs harder.

3. Moderate disability; balance loss.

4. Severe disability; ambulates with aid.

5. Wheelchair/bed-bound; total care.
   • Diagnostics – mainly clinical; DAT scan/MRI support; expanding genetic panels.

Peripheral Neuropathy

• Demyelination of peripheral axons → pain, paresthesia, weakness.
• Causes – diabetes, vitamin \text{B12} deficiency, back injury, toxins, autoimmune, hereditary.
• Wallerian degeneration → foot/ankle weakness.
• Work-up – med review, EMG, \text{B12} labs, CT/MRI spine.
• Tx – gabapentin, pregabalin, NSAIDs, \text{B12} injections if deficient.

Multiple Sclerosis (MS)

• Immune-mediated CNS demyelination & axonal loss.
• Types – relapsing-remitting, primary progressive, secondary progressive, clinically isolated.
• McDonald criteria – ≥2 clinical attacks/lesions in ≥2 CNS areas or MRI equivalents.
• Hallmark pains – trigeminal neuralgia, Lhermitte’s sign (electric spine shock on neck flexion), “MS hug”.
• Symptoms – vision loss, nystagmus, spasticity, ataxia, cognitive decline.
• Tx – disease-modifying agents, high-dose steroids for relapses, PT/OT, bowel-bladder regimens, cognitive rehab.

Dementia Spectrum

• Progressive global cognitive decline w/o altered LOC.
• Types
• Vascular – ischemic burden post-stroke.
• Lewy body – alpha-synuclein; hallucinations, parkinsonism.
• Frontotemporal – proteinopathy frontal/temporal lobes → behavior/language change.
• Mixed – combinations.

Alzheimer’s Disease (AD)

• Most common dementia – beta-amyloid plaques + tau tangles → cortical atrophy.
• Early sign – short-term memory loss.
• Risk – age, family history, APOE-\varepsilon4 allele; modifiable: HTN, inactivity, diet.
• Forms – early-onset (genetic, rare) vs late-onset/sporadic – 7^{\text{th}} leading cause of death.
• Diagnostics – CT/MRI atrophy, amyloid PET, CSF biomarkers, serial Mini-Mental (vary questions).
• Tx – cholinesterase inhibitors (donepezil), NMDA antagonist (memantine); slow decline, not curative.
• Caregiver strain huge – offer respite resources/support groups.

Delirium

• Acute, fluctuating confusion & altered LOC.
• Causes – drugs, ETOH, anesthesia, infection (UTI in elderly), electrolytes, hypoxia, ICU sensory deprivation (“ICU psychosis”).
• Reversible if underlying issue addressed promptly.

General Nursing & Environmental Strategies

• Safety – remove rugs, adequate lighting, bed alarms, helmets/seatbelts/fall-prevention to ↓TBI & SCI.
• Orientation aids – clocks, calendars, family photos.
• Sensory modulation – reduce overload for ↑ICP/migraine; increase stimulation for hypoactive delirium or daytime wakefulness in dementia.

Examination Tip

• Instructor permits one 4 \times 6-in index card (both sides) for upcoming exam; still master material for cumulative final.