Understanding ABGs - having trouble, any ideas?

  1. I am doing an ICU rotation right now and so I need to be able to interpret ABGs. I'm not understanding them very well, and wondered if anybody knew of a "dumbed down" explanation anywhere? I am sure I'm just making it harder than it is, but I have patients to care for and tests to pass and I really do need to understand it!
  2. Visit future L&Dnurse profile page

    About future L&Dnurse

    Joined: Nov '06; Posts: 266; Likes: 79


    [font="comic sans ms"]try this link future l&d nurse!

    hope it helps ~ cheers ,
  4. by   SuesquatchRN
  5. by   laurainri
    Quote from Suesquatch
    OMG !!! tic tac toe is the only way to go... you are so hung up on undertstanding the values that it does not process. this helps you get the value you are looking for. with and without compenstion. after that it is a piece of cake
    [font="comic sans ms"]i also found this link that day to nite provided from a previous allnurses forum regarding abgs. you could also try this site as well.

    cheers ,
  7. by   nurz2be
    Here are a few that I found




  8. by   Conrad283
    First you need the norms:

    pH: 7.35 - 7.45
    CO2: 35 - 45
    HCO3: 22 - 26


    pH: high CO2: norm HCO3: high - metabolic alkalosis
    ex: 7.50|40|30
    pH: low CO2: norm HCO3: low - metabolic acidosis
    ex: 7.30|40|20
    pH: high CO2: low HCO3: norm - respiratory alkalosis
    ex: 7.47|30|24
    pH: low CO2: high HCO3: norm - respiratory acidosis
    ex: 7.27|50|23

    Those are basic abg's if the world is all good. But in the case where it's not there are two situations that can occur.

    Compensated ABG's are where the pH is NORMAL, but the CO2 and HCO3 are NOT normal.
    1) You have to break the pH up 7.35 - 7.4 is acidotic, and 7.4 - 7.45 is alkaline.
    2) Match the CO2 of HCO3 to the pH using the basics (above)
    3) The fact that the other value is out of range makes it compensated.

    ex: 7.43|30|20 - compensated respiratory alkalosis. etc

    Then there's partial compensatory. I'm not very familiar with this, so I don't want to say the wrong thing

    Hope this helps.
  9. by   Daytonite
    this gets asked so much i can't believe we still haven't gotten all the links into a sticky thread that we can find yet!

    go to these older threads for weblinks to sites that have abg tutorials and information on how to read and interpret abgs:
    Last edit by Daytonite on Nov 10, '07
  10. by   future L&Dnurse
    Thanks so much!! I am going to spend a lot of time on those links in the next few weeks, I bet. I don't think I've struggled with anything else as much as ABGs, so I will take all the help I can get. Thank you everyone!