Neuroanatomy & Disorders Overview

Overview

This lecture provides a comprehensive review of fundamental neuroanatomy, neurological assessments, common neurological disorders, seizure types, and key nursing considerations for neuro patients.

Neuroanatomy & Physiology

• The frontal lobe controls behavior, mood, and emotion.
• The brainstem regulates breathing, swallowing, balance, movement, and consciousness.
• Each brain hemisphere controls the opposite side of the body.
• The parasympathetic nervous system supports rest-and-digest effects like decreased heart rate and increased digestion.

Spinal Nerves & Function

• There are 8 cervical spinal nerves.
• There are 5 lumbar and 5 sacral spinal nerves.
• The cerebellum’s function is evaluated through coordination and balance testing.

Neurological Assessment & Diagnostics

• Neurovascular assessments include pulses, sensation, movement, capillary refill, temperature, and pain.
• A ≥2 point drop in Glasgow Coma Scale (GCS) is significant and should be reported.
• A positive Romberg sign (swaying with eyes closed) suggests cerebellar dysfunction.
• Cerebral arteriography is the gold standard for detecting brain vascular issues; check allergies, kidney function, and anticoagulant use prior.
• MRI is contraindicated for confused/agitated patients, unstable vital signs, ongoing life support, and possibly those with old tattoos.
• Lumbar puncture withdraws CSF from the subarachnoid space; do not perform with increased intracranial pressure.
• Normal CSF is clear and colorless.

Aging & Neurologic Changes

• Aging can cause slower reflexes, decreased sensation, and impaired memory.

Common Neurological Disorders

• Parkinson’s disease is treated with medications like levodopa.
• Carbamazepine treats epilepsy and neuropathic pain (e.g., trigeminal neuralgia).
• Trigeminal neuralgia causes severe facial pain affecting the trigeminal nerve.
• Decorticate posturing occurs due to brain injury, bleed, tumor, or poisoning.
• Decerebrate posturing is due to lower brain or pons lesions.
• Guillain-Barré syndrome is an ascending inflammatory disease of the PNS.
• Bell’s palsy is facial paralysis from CN VII dysfunction, often on one side.
• Herpes simplex virus can cause encephalitis.
• Multiple sclerosis is a chronic CNS disease with autoimmune myelin attack and relapse/remission.
• Meningitis is the inflammation of the meninges, with signs like headache, fever, stiff neck.

Intracranial Pressure (ICP) & Early Signs

• Early sign of neuro deterioration is decreased level of consciousness (LOC).
• Signs of increased ICP include headache, vomiting, altered LOC, and pupil changes.
• Pupillary changes help detect brain injury, herniation, or increased ICP.

Seizures & Epilepsy

• Causes of seizures include fever, trauma, metabolic disturbances, tumors, and drugs.
• The prodromal stage is when symptoms begin before seizure onset.
• The aura stage provides warning (dizziness, altered senses).
• Status epilepticus is a seizure lasting over 5 minutes without recovery.
• Generalized seizures affect both hemispheres; partial (focal) seizures are localized.
• Tonic-clonic (grand mal) seizures involve muscle rigidity and may begin with aura.
• Epilepsy involves two or more unprovoked seizures within 24 hours.

Alzheimer's Disease & Cognitive Disorders

• The 5 A’s of Alzheimer’s are amnesia, anomia, apraxia, agnosia, and aphasia.

Key Terms & Definitions

• Romberg sign — test for cerebellar dysfunction: swaying with eyes closed.
• GCS (Glasgow Coma Scale) — assesses level of consciousness.
• Status epilepticus — seizure activity >5 minutes or multiple seizures without regaining consciousness.
• Prodromal phase — pre-seizure symptom period.
• Aura — sensory disturbance before a seizure.
• Decorticate/Decerebrate posturing — abnormal body postures due to brain injury.
• Bell’s palsy — CN VII dysfunction causing facial muscle weakness.
• Meningitis — inflammation of the protective brain membranes.

Action Items / Next Steps

• Review causes and signs of increased ICP and meningitis.
• Memorize the 5 A’s of Alzheimer’s and seizure stages.
• Practice neuro assessment skills including GCS and cranial nerve checks.