IBCC Episode 128 - ABG, VBG and Pulse Oximetry

Metadata

• Author: The Internet Book of Critical Care Podcast
• Full Title: IBCC Episode 128 - ABG, VBG and Pulse Oximetry
• Category: #podcasts
• URL: https://share.snipd.com/episode/3a7a6148-8e0e-4364-8fdf-1193131e2f64

Highlights

• Episode AI notes
  1. The AA gradient is an index of lung function that compares the inspired PO2 and the patient's blood, PAO2.
  2. It can differentiate between vocal cord dysfunction and severe asthma.
  3. A normal AA gradient may support a diagnosis of vocal cord dysfunction, while an elevated gradient may suggest severe asthma.
  4. There are niche applications where the AA gradient can be helpful, but it is not useful in critical care. (View Highlight)
• The AA Gradient: A Classic Index of Lung Function
  Key takeaways:
  • AA gradient is an index of how well the lungs are working.
  • It can be useful in certain situations, such as distinguishing between vocal cord dysfunction and severe asthma.
  • A normal AA gradient may support a diagnosis of vocal cord dysfunction, while an elevated gradient may suggest severe asthma.
  • There are niche applications where the AA gradient can be helpful.
  • It's not useful in critical care, however.
    Transcript:
    Speaker 1
    Yeah. No, absolutely. So we have currently and it's kind of what we need to use based on our current evidentiary basis until folks can validate something that's better. So that's me setting up an AA graded conversation, Josh. Why is this still out there? The AA gradient is this classic thing that we all learned about in med school where it's the difference between the inspired PO2 and the patients blood, PAO2, and it's an index of how well the lungs are working. And it can be useful in a couple of situations. So there are some niche applications where it can be helpful. So for example, if a patient comes in and you're trying to sort out like vocal cord dysfunction versus severe asthma, if you can have them breathe through mirror, if you can get an AA gradient and if it's normal, then that may support a diagnosis of vocal cord dysfunction, whereas if the AA gradient is elevated, that might push you towards severe asthma. There are these like kind of niche applications where the AA gradient can be useful. When on the other side of that coin, is it not useful in critical care then? (Time 0:11:42)