Pulmonology Coding Alert

Question: What's the difference between aerosol and gaseous ventilation?Answer: Both aerosol (78586, 78587) and gaseous (78591, 78593, 78594) studies are part of the ventilation code series. Aerosol tests involve the patient inhaling nebulized (reduced to a fine spray) aerosol agents with radioactive particles. The key term to look for indicating aerosol is "DTPA," the radioactive aerosol the provider has the patient inhale. Sometimes you would encounter other terms such as Technetium DTPA, particulate, and mist.Physician's note for gaseous ventilation studies usually refer to the gas used, typically Xenon gas (such as Xenon-133 or Xe 133). Another possibility is Krypton gas (Krypton-81 or Kr 81), although you may not see this much in practice.CPT further distinguishes gaseous ventilation studies by whether the patient takes only a single breath or the patient does rebreathing and washout with plain oxygen. "Rebreathing" is inhalation of the gas previously exhaled. "Washout" is the elimination of [...]