CCRN Review Lecture Notes

Introduction

  • Lecture given by Courtney Baker, Clinical Director at Grady, focused on details regarding CCRN material and neuroanatomy.

Anatomy Review

  • Overview of the brain's lobes, cranial nerves, and their clinical significance.

Lobes of the Brain

  • Frontal Lobe:   - Responsible for judgment and reasoning.   - Provides motor function and coordination.   - Damage can result in impulsive behavior.

  • Parietal Lobe, Occipital Lobe, Temporal Lobe:   - Relevant for understanding stroke signs and symptoms related to damage in specific areas.

Cranial Nerves

  • Total of 12 cranial nerves; important for neurological assessment.

  • Key nerves include:   - Ocular Motor (CN III): Pupil assessment.   - Facial (CN VII): Facial movement assessment.

Circle of Willis

  • Vital in maintaining collateral circulation and brain perfusion during vascular events.

Spinal Cord

  • Importance of protecting the cervical, thoracic, and lumbar regions of the spinal cord from injuries.

Cerebral Blood Flow

  • Brain requires a constant supply of oxygen and glucose.

  • Cerebral Perfusion Pressure (CPP):   - Calculated as CPP = Intracranial Pressure (ICP) - Mean Arterial Pressure (MAP).   - Normal CPP: 60-110 mm Hg; <60 indicates inadequate brain perfusion leading to anoxia.

Factors Affecting Cerebral Blood Flow

  • Increases:   - Hypercapnia   - Hypoxemia   - Fluid overload   - Hyperthermia   - Vasodilating drugs

  • Decreases:   - Hypocapnia (causing vasoconstriction)   - Diuretics (decreasing edema)   - Normothermia is preferred; hypothermia is better than hyperthermia.   

Neurological Assessment

  • Initial assessment begins with mental status change.   - Changes can indicate issues before pupillary reactions.

  • Motor Function:   - Check for symmetry in movement.   - Contralateral weakness due to stroke (right stroke = left weakness).   - Severe possibilities involve disability and posturing (decorticate).

Pupil Assessment

  • Reflects intracranial pressure with asymmetrical pupils noted during a bleed.   - Ipsilateral changes, relating to the location of the stroke (e.g., right-side stroke affecting right pupil).

Glasgow Coma Scale (GCS) and NIHSS

  • Essential tools for assessing neurological function.

Symptoms of Increased ICP

  • Early signs: Change in consciousness.

  • Late signs: Fixed and dilated pupils, Cushing's triad (hypertension, bradycardia).

Spinal Cord Injuries

  • Caused by trauma, disease, tumors, or abscesses.

  • Common injury causes involve:   - Trauma (accidents)

  • Specific treatment and precautions to maintain C-spine stability.

Brown-Séquard Syndrome

  • Hemi transaction causing ipsilateral motor loss and contralateral sensory loss.

Autonomic Dysreflexia

  • Affects injuries at T6 and above. Causes:   - Disassociation of sympathetic and parasympathetic responses.   - Symptoms include severe headache, hypertension, and altered heart rate.

  • Treatment involves addressing the stimulus (e.g., full bladder).

Stroke Overview

Types:

  1. Ischemic Stroke:    - Caused by clots or plaque, typically acute.    - 85% of strokes; symptomatic evaluation includes slurred speech, facial droop.    - Treatment includes CT scans and possible thrombolysis (e.g., TPA).

  2. Hemorrhagic Stroke:    - Due to vessel rupture or hypertension.    - Presents with sudden onset of severe headache, altered consciousness.    - Management includes careful blood pressure regulation.

Stroke Management Goals

  • Permissive hypertension in ischemic strokes to enhance perfusion.

  • Target blood pressure control in hemorrhagic strokes.

  • Early CT scanning and timely interventions are critical.

Intracranial Hemorrhage

  • Commonly associated with hypertension and trauma.

  • Requires careful monitoring of blood pressure and neurological status.

Subarachnoid Hemorrhage

  • Signs include severe headache and possible loss of consciousness.

  • Management: Blood pressure control, monitoring for vasospasms, possible surgical intervention.

Hydrocephalus

  • Caused by impaired CSF flow; requires potential shunting.

  • Symptoms include increased head size in infants and gait changes in adults.

Seizures

  • Varieties include clonic, absence, a tonic, and subclinical.

  • Often requires EEG monitoring and potential sedation.

Delirium and Dementia

  • Increased risk in ICU patients, especially those on prolonged sedation.

Neurological Infections

Meningitis

  • Inflammation of meninges by bacteria or virus.

  • Bacterial presents more aggressively than viral.

Neuromuscular Disorders

  • Multiple Sclerosis (MS): Autoimmune demyelination; gradual, affecting sensory, cognitive, and motor skills.

  • Guillain-Barré Syndrome: Ascending paralysis following infection.

  • Myasthenia Gravis: Descending paralysis due to antibody-mediated loss of acetylcholine.

Conclusion and Key Takeaways

  • Emphasize the anatomy of the brain and its functional significance in clinical assessment.

  • Monitor signs of neurological change carefully and continuously.

  • Early intervention and recognition of stroke symptoms can significantly impact patient outcomes.

  • Preparation for exams like CCRN requires in-depth understanding of the anatomy, physiology, and pathology of neurological issues covered in this lecture.