# ABG Analysis

1. Anyone have an easy way of explaining this to me? I keep reading over this chapter and it's just getting all jumbled in my head.

Respiratory acidosis/alkalosis, Metabolic acidosis/alkalosis .... I really just don't understand the "compensation" part of this. How do I know if it's uncompensated or compensated?

Can anyone give me any ideas here, please! My brain is starting to hurt
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3. This was the hardest yet most interesting part of nursing school for me along with hemodynamics. Probably why I ended up in the ICU!

4. Quote from RainDreamer
Anyone have an easy way of explaining this to me? I keep reading over this chapter and it's just getting all jumbled in my head.

Respiratory acidosis/alkalosis, Metabolic acidosis/alkalosis .... I really just don't understand the "compensation" part of this. How do I know if it's uncompensated or compensated?

Can anyone give me any ideas here, please! My brain is starting to hurt
Simple -
If the pH is normal, it is compensated (body has compensated for the problem through it's own pathways, thus normalizing the pH)

If the pH is abnormal, it is UNcompensated (body has not compensated for the problem or body's compensation mechanisms were ineffective).
5. This is the really quick, non detailed way that I think about it (without getting into compensation or mixed/acid base issues)
First, I look at pH...normal is 7.35-7.45...So is the pH that I am looking at normal? If yes, than everything is fine or something is compensating to make it normal.

Next I think respiratory (the faster of the two systems)...this is the paco2...normal is 35-45 (I remember this number because it reminds me of the normal pH...after the decimal point that is...). paco2 and pH work like a see-saw....if one is low the other is high...ie: if the paco2 is low (<35) and the pH is high >7.45- you have respiratory alkalosis...(the patient is probably hyperventilating due to come cause).... On the other hand, if the pH is low (<7.35) and the pco2 is high (>45) it is respiratory acidosis--hypoventilation (again your job to figure out why).

Next I think about metabolic (the slower of the two systems)...this is reflected by the hco3....normal is 22-26...pH and hco3 work in tandem (vs. the see-saw like paco2 and pH). So, if your pH is low (7.35) and your hco3 is low (<22) you have metabolic acidosis (again both are low--not see-saw). If your pH is high (>7.45) and your hco3 is high (>26) you have metabolic alkalosis going on....again there are various reasons for these situations but it is more in-depth and requires more typing....

FYI: check out the thread that begalli directed you to...some good easy to follow info on that thread!
Last edit by zambezi on Feb 20, '05
6. Quote from begalli
This was the hardest yet most interesting part of nursing school for me along with hemodynamics. Probably why I ended up in the ICU!

Thanks for the link! I've been a med/surge nurse now for 4 1/2 yrs and I STILL have a hard time w/ ABGs. It can never hurt to do a refresher!
7. begalli, RN4NICU, zambezi ..... thank you all so much!!!! That really helped a lot. And thank you to NurseFirst and ILuvBabies that posted info on the other thread too. All of that info helped a lot .... and those links with the practice problems on it, very helpful!!

It was just all so jumbled in my head, and now it makes a lot more sense, took my exam today and I think I did very well! Thanks again!!
8. Quote from RainDreamer
...took my exam today and I think I did very well!

Yay!!!
9. Hey, I learned something too..