Need help with an ABG problem. (Compensation)

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pH 7.01

PaCO2 70

HCO3 17

I said it's respiratory/metabolic acidosis that is partially uncompensated. Is that correct?

I was told if pH is abnormal, PaCO2 is abnormal, and HCO3 is abnormal, then it's partially uncompensated.

So is it partially uncompensated?

Your patient is likely dead so I'd consider your patient permanently decompensated 😉

Your patient is likely dead

I just snorted. Thanks for the laugh.

I just snorted. Thanks for the laugh.

I always hated trying to figure out those compensated and uncompensated respiratory vs metabolic acidosis/alkalosis blood gases.

I always hated trying to figure out those compensated and uncompensated respiratory vs metabolic acidosis/alkalosis blood gases.

Me too. I still have little to no clue how to tell uncompensated from partially compensated.

Me too. I still have little to no clue how to tell uncompensated from partially compensated.

If pH is NORMAL, pCO2 and HCO3 are both ABNORMAL = Compensated

If pH is ABNORMAL, pCO2 and HCO3 are both ABNORMAL = Partially Compensated

If pH is ABNORMAL, pCO2 or HCO3 is ABNORMAL = Uncompensated

If pH is NORMAL, pCO2 and HCO3 are both ABNORMAL = Compensated

If pH is ABNORMAL, pCO2 and HCO3 are both ABNORMAL = Partially Compensated

If pH is ABNORMAL, pCO2 or HCO3 is ABNORMAL = Uncompensated

You must also distinguish the difference between metabolic and respiratory and whether it's acidosis or alkalosis.

I'm going to try to send you a pm that may help

pH 7.01

PaCO2 70

HCO3 17

It's important to understand the concept of compensation. Let's say that you have a patient that has been vomiting for hours... you would expect them to be alkalotic, thus pH would be > 7.45 and HCO3 would be > 26... making it metabolic.

When the body realizes that it's in an alkalotic state it will try something else to bring the pH back into balance -- thus it will slow down respirations to hold on extra acid CO2 and this would put their CO2 > 45 during the compensation phase.

The numbers you have listed are all acidotic.. so there is something serious going on with this patient, but it's not compensation.

pH 7.01

PaCO2 70

HCO3 17

I said it's respiratory/metabolic acidosis that is partially uncompensated. Is that correct?

I was told if pH is abnormal, PaCO2 is abnormal, and HCO3 is abnormal, then it's partially uncompensated.

So is it partially uncompensated?

203bravo gave a good explanation to help you think in terms of *what* compensation is actually referring to. To be clear, an ABG can be compensated (pH is corrected by compensatory system), partially compensated (compensatory system has kicked in to help correct pH, but pH is still abnormal), or uncompensated. There is no partially uncompensated when it comes to blood gases.

What your gas shows is an uncompensated combined (or mixed) respiratory and metabolic acidosis. The pH is acidotic and both the respiratory and metabolic components are outside of their normal limits in an acidotic direction. Neither the respiratory nor the metabolic system is attempting to correct the pH, and that's what compensation is all about.

Please consider searching AN for "grntea ABG" - she has some lengthy posts (and may come along her to directly impart her wisdom on you) that would be extremely helpful for someone learning to tackle ABG interpretation.

Specializes in Burn ICU.

This helped me TONS.

Specializes in Pediatric Hematology/Oncology.

Someone posted this a while back and it has helped me SO much:

https://abg.ninja/abg

Christine...this is totally off topic but I am from the Houston area and I work for HCA. I just posted a question about clinicals in our area. I would be most grateful if you or any of your friends that are in clinicals with you would answer some or all of my questions. Thanks so much! :)

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