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Syncope

Transient loss of consciousness due to global cerebral hypoperfusion, often with rapid onset, brief duration, and spontaneous recovery

• A key differential in cerebrovascular cases, distinct from stroke, TIA, and seizures

Clinical Presentation

• Preceding Symptoms: Dizziness, lightheadedness, nausea, pallor, diaphoresis
• Triggers:
  • Prolonged standing, vasovagal (emotional stress)
  • Orthostatic hypotension (sudden positional changes)
  • Exertion (suggests cardiac causes)
• Key Differentiation: Absence of focal neurological deficits distinguishes syncope from stroke or TIA

Labs, Studies, and Physical Exam Findings

• Initial Focus: Rule out life-threatening causes (arrhythmias, structural heart issues)
• Vital Signs: Orthostatic blood pressure and heart rate changes. Drop in systolic BP ≥20 mmHg or diastolic ≥10 mmHg suggests orthostatic hypotension
• Cardiovascular Exam:
  • Arrhythmias
  • Murmurs (e.g., aortic stenosis)
  • Signs of heart failure (JVD, edema)
• Neurological Exam:
  • Rule out stroke or TIA
  • Normal findings in most syncope cases
• Signs of Dehydration or Hypovolemia: Dry mucous membranes, delayed capillary refill, decreased skin turgor
• Studies:
  • ECG: Evaluate for arrhythmias or ischemia
  • Tilt Table Test: Diagnostic for vasovagal syncope
  • Holter Monitor or Echocardiogram: Investigate cardiac causes
• Imaging: CT or MRI is unnecessary unless focal deficits are present

Treatment

• Vasovagal: Educate on trigger avoidance, increase salt/fluid intake, consider beta-blockers for refractory cases
• Orthostatic: Hydration, slow positional changes, compression stockings
• Cardiac: Address arrhythmias or structural abnormalities (pacemaker for bradycardia)

Hydrocephalus

Excess cerebrospinal fluid (CSF) accumulation in the brain’s ventricles, leading to increased intracranial pressure (ICP)

• Types:
  • Communicating: Impaired CSF absorption (e.g., post-meningitis scarring)
  • Non-communicating: Obstruction within ventricles

Clinical Presentation

• Infants:
  • Enlarged head circumference noted by parents or during routine well-child checks
  • Difficulty feeding, persistent irritability, developmental delays
  • “Sunsetting eyes” (downward gaze) observed by caregivers
• Adults:
  • Gradual onset of difficulty walking, described as imbalance or shuffling gait
  • Complaints of worsening memory or confusion, often mistaken for dementia
  • New or worsening urinary incontinence, reported as urgency or accidents
• Acute Symptoms:
  • Sudden severe headache and nausea/vomiting
  • Altered mental status, including confusion or lethargy

Labs, Studies, and Physical Exam Findings

• Physical Exam:
  • Infants: Enlarged head circumference, bulging fontanelles, split cranial sutures, “sunsetting eyes”
  • Adults:
    • Signs of increased intracranial pressure:
    • Papilledema
    • Cranial nerve VI palsy (diplopia)
    • Cushing’s triad: hypertension, bradycardia, irregular respirations
    • Gait instability (broad-based or shuffling)
    • Cognitive impairment on mental status examination
• Imaging:
  • CT or MRI: Enlarged ventricles with or without signs of obstruction
  • Ultrasound: Useful in infants with open fontanelles
• Additional Studies:
  • Lumbar puncture: Contraindicated in cases of acute increased ICP but diagnostic in normal pressure hydrocephalus (symptom relief post-LP supports the diagnosis)
  • ICP monitoring: For severe cases to guide management

Treatment

• Acute Management:
  • Emergency external ventricular drain (EVD) to reduce ICP
  • Mannitol or hypertonic saline for temporary ICP reduction
• Chronic Management:
  • Ventriculoperitoneal (VP) Shunt: Standard treatment for long-term CSF diversion
  • Endoscopic Third Ventriculostomy (ETV): Surgical option, especially for non-communicating hydrocephalus
• Normal Pressure Hydrocephalus (NPH):
  • VP shunt placement after confirmed diagnosis with lumbar puncture or large-volume CSF removal trial

Key Insights

• Normal pressure hydrocephalus often presents subtly—always suspect in an older adult with the classic triad
• A sudden deterioration in a patient with known hydrocephalus and a shunt should prompt evaluation for shunt malfunction or infection
• Monitor for herniation signs (e.g., Cushing’s triad) in acute increased ICP, as these are life-threatening

Coma

A state of unresponsiveness where the patient cannot be awakened, lacks awareness, and does not respond to external stimuli

• Results from widespread cortical dysfunction, brainstem damage, or both
• Common causes include metabolic derangements, structural brain damage, or diffuse neuronal dysfunction

Clinical Presentation

• Patient is unresponsive and fails to react purposefully to verbal commands, physical stimulation, or environmental cues
• History (if available from witnesses):
  • Sudden collapse suggests stroke, cardiac arrest, or trauma
  • Gradual decline suggests metabolic or toxic causes
  • Associated symptoms like fever, infection, seizure activity, or recent trauma

Labs, Studies, and Physical Exam Findings

• Primary Survey: Focus on stabilizing ABCs (airway, breathing, circulation)
• Physical Exam:
  • Neurological findings:
    • Glasgow Coma Scale (GCS)

      GCS is used to track changes over time and guide management decisions, including the need for airway protection, imaging, or neurocritical care intervention.

      • Eye-Opening (E):
        • 4: Spontaneous
        • 3: To verbal command
        • 2: To pain
        • 1: None
      • Verbal Response (V):
        • 5: Oriented
        • 4: Confused conversation
        • 3: Inappropriate words
        • 2: Incomprehensible sounds
        • 1: None
      • Motor Response (M):
        • 6: Obeys commands
        • 5: Localizes to pain
        • 4: Withdraws from pain
        • 3: Decorticate posturing (flexion to pain)
        • 2: Decerebrate posturing (extension to pain)
        • 1: None

    Scoring and Interpretation:

    • Total Score: 3 to 15
    • 13–15: Mild brain injury or fully conscious
    • 9–12: Moderate brain injury
    • ≤8: Severe brain injury, often indicates the need for intubation and close monitoring
    • Pupillary response: Fixed and dilated pupils (brainstem herniation); pinpoint pupils (opioids or pontine damage)
    • Corneal reflexes: Absent reflex indicates brainstem dysfunction
    • Motor response to pain: Decorticate posturing (cortical damage); decerebrate posturing (brainstem damage)
    • Gag and cough reflexes: Absent reflexes suggest brainstem involvement
  • Signs of trauma: Bruising, lacerations, or skull fractures
  • Skin findings: Needle marks (overdose), rash (meningitis, sepsis)
• Imaging:
  • CT or MRI: Rule out stroke, hemorrhage, mass lesions, or herniation
  • Cervical spine imaging: If trauma is suspected
• Laboratory Studies:
  • Blood glucose: Hypoglycemia is a reversible cause of coma
  • Toxicology screen: Detects drugs or toxins
  • Arterial blood gas (ABG): Identifies hypoxia, hypercapnia, or metabolic acidosis
  • Electrolytes and renal function: Detect imbalances or organ failure
  • Infectious workup: Blood cultures, lumbar puncture if infection (e.g., meningitis, encephalitis) is suspected
• Additional Studies:
  • EEG: Rules out nonconvulsive status epilepticus
  • ICP monitoring: In cases of suspected elevated intracranial pressure

Treatment

• Immediate Stabilization:
  • Ensure airway patency, oxygenation, and adequate circulation
  • Intubation if necessary
• Reversible Causes:
  • Correct hypoglycemia with dextrose
  • Administer naloxone if opioid overdose is suspected
  • Treat electrolyte imbalances (e.g., hyponatremia, hypercalcemia)
  • Manage seizures with antiepileptics
• Neuroprotection:
  • Reduce ICP with head elevation, hypertonic saline, or mannitol
  • Consider emergent surgical intervention for mass lesions or hemorrhage
• Specific Treatments:
  • Antibiotics/antivirals for meningitis or encephalitis
  • Anticoagulation reversal for hemorrhagic stroke