Barium


Chemistry


Clinical Manifestations

Barium Aspiration

Physiology

  • Accidental Aspiration of Barium Sulfate Contrast During Upper GI Examination
    • Barium Sulfate: relatively insoluble barium salt
      • Pulmonary toxicity, if aspirated
  • Potential for Pulmonary Toxicity of Other Radiographic Contrast Agents
    • Iopydol (Hytrast): commonly used for bronchography in the past
      • No pulmonary toxicity
    • Amidotrizoat (Gastrograffin) (Gastrograffin, [[Gastrograffin]]): non-absorbable, hyperosmolar, hypertonic water-soluble contrast media
      • May cause acute lung injury, if aspirated
    • Iodixanol (Visipaque): isoosmolar contrast medium (mainly used for intrarterial and IV contrast studies)
      • No pulmonary toxicity

Clinical

Treatment

  • Supportive Care

Barium Intoxication

Physiology

  • Barium Carbonate/Barium Hydroxide Rodenticide Ingestion
    • Route of Exposure: accidental or intentional ingestion
  • Barium Chlorate
    • Used in fireworks and explosives
    • Route of Exposure: ingestion, inhalation, or burns
  • Barium Nitrate
    • Used in manufacture of TNT
    • Route of Exposure: ingestion, inhalation, or burns

Diagnosis

  • Barium Level: elevated (normal range: 3-29 ug/dL)

Clinical

  • Metabolic Manifestations
    • Hypokalemia (see Hypokalemia [[Hypokalemia]])
      • Physiology: barium decreases potassium efflux from muscle cells by blocking potassium channels (with no activity on the sodium-potassium ATP-dependent pump) -> extracellular hypokalemia and intracellular hyperkalemia
      • Muscle accounts for approxmately 44% of body mass -> serum potassium level decreases (sometimes precipitously) resulting in paralysis
      • Clinical: may result in acute respiratory failure
    • Hypophosphatemia (see Hypophosphatemia, [[Hypophosphatemia]])
    • Rhabdomyolysis (see Rhabdomyolysis, [[Rhabdomyolysis]])
  • Cardiac Manifestations
    • Arrhythmias
    • Asystole
    • Congestive Heart Failure (CHF) (see Congestive Heart Failure, [[Congestive Heart Failure]])
    • Hypertension (see Hypertension, [[Hypertension]])
    • QT prolongation
  • Neurologic Manifestations
    • Anxiety (see Anxiety, [[Anxiety]])
    • Mydriasis (see Mydriasis, [[Mydriasis]])
    • Headache (see Headache, [[Headache]])
    • Confusion (see Delirium, [[Delirium]])
    • Myoclonus/Trismus (see Myoclonus, [[Myoclonus]])
    • Perioral/Face/Hand Paresthesias with Preserved Sensation
    • Seizures (see Seizures, [[Seizures]])
  • Gastrointestinal Manifestations

Treatment

  • Gastric Lavage with Sodium Sulfate: may be indicated for barium ingestion
    • Sulfate precipitates with barium, forming non-toxic barium sulfate
  • Charcoal: ineffective for barium ingestion
  • Hemodialysis (see Hemodialysis, [[Hemodialysis]]): effective at removing barium, but generally not necessary
  • Aggressive Potassium Replacement: preferred treatment (even though total body potassium levels are likely not decreased in the setting of barium intoxication)
    • Serum potassium level must increase enough to displace barium from the potassium channels -> with replacement, symptoms decrease by 24 hrs later
  • Treatment of Arrhythmias: treat with potassium replacement, rather than antiarrhythmics
  • Treatment of Hypertension: nitroglycerin is preferred

References