ABG interpretation

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Hello Everyone!

I have a question and I am hopeful someone here can help me interpret this ABG:

pH, 7.45; PCO2, 30; HCO3, 29; O2 Sat, 94%

I think it is metabolic alkalosis, but would like to get some feed back to ensure I am in the right direction with this.

Thanks in advance for your help in guiding me in the right direction!







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Your pH is within normal range though it is on the alkaline side. Your C02 is low which would be alkalotic and the HCO3 is alkaline. The best way to look at it is if you drew and arrow and your pH and CO2 had arrows moving the opposite direction it would be a respiratory issue and if they are pointing the same direction it is a metabolic issue. So in this case you have Respiratory Alkalosis that is fully compensated because your pH is within the normal range. Hope this helps!

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Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.

This may help......

VickyRN

This is a fun “bingo” type exercise I developed for my nursing class several years ago. The idea is not original – I had heard about this before – but the attached documents are my adaptation of the idea.

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Your pH is normal high (above 7.41) so it is alkalosis - your pco2 is 30 (normal 35-45) so it's low and your Hc03 is high at 29 (normal 22-26)

Think of Rome (Resp opposite metabolic equal). If the ph and hco3 are both high then YES IT IS METABOLIC ALKALOSIS!!!!

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Hello Everyone! I have a question and I am hopeful someone here can help me interpret this ABG: pH, 7.45; PCO2, 30; HCO3, 29; O2 Sat, 94% I think it is metabolic alkalosis, but would like to get some feed back to ensure I am in the right direction with this. Thanks in advance for your help in guiding me in the right direction!

It looks like Resp and Met Allalosis to me????

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pH 7.45 is within normal range although on the edge to alkaline

PaCO2 also within normal range

O2 sat is within normal range as well

HCO3- is high.

Looks like Metabolic alkalosis not compensated

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Correction: PaCO2 30 is not within normal range...This patient is hypocapneic to begin with. HCO3- level should be below 22 but if patient stays hypocapneic for long enough bicarb secretion increase (maybe to 29)

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pH 7.45 is within normal range although on the edge to alkaline

PaCO2 also within normal range

O2 sat is within normal range as well

HCO3- is high.

Looks like Metabolic alkalosis not compensated

How do you see that the CO2 is within normal range? 35-45 is normal for CO2. Below 35 is alkalosis and above 45 is acidosis. Also, 02 sat does not really matter when interpreting ABG's because the hemoglobin could be saturated with CO2 instead of O2 so you could get a false reading. Your paO2 is what is important.

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Sorry about that, you fixed it before my reply was posted.

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This patient has respiratory alkalosis to begin with..the pH should be above 7.45 or Bicarb beliw 22 because the body strive for homeostasis. Low CO2 means less carbonic acid pxn. if hypocapnia last for long enough, more bicarb is produced by the kidneys to pull the H+ out of the cells and form an acid (H+HCO3>H2CO3). It seems to me that this is why this patient has high bicarb levels. I don't know if this is a real or hypothetic case but it may help to check the potassium level to get an idea of what's happening.

This is really interesting and I sure want to know what is the Dx..please keep us updated.:)

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This patient has respiratory alkalosis to begin with..the pH should be above 7.45 or Bicarb beliw 22 because the body strive for homeostasis. Low CO2 means less carbonic acid pxn. if hypocapnia last for long enough, more bicarb is produced by the kidneys to pull the H+ out of the cells and form an acid (H+HCO3>H2CO3). It seems to me that this is why this patient has high bicarb levels. I don't know if this is a real or hypothetic case but it may help to check the potassium level to get an idea of what's happening.

This is really interesting and I sure want to know what is the Dx..please keep us updated.:)

This is a case study I am working on for Pharm. So it is hypothetical, but the potassium levels are normal (4.0). The patient in this study had aspergillosis pneumonia.

Thank you everyone for your helpful advice! :)

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Thank you Esme12!! Appreciate the worksheets!!! :)

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