A UWorld question gave me a patient with:
pH 7.23
PaO2 88
PaCO2 40
HCO3- 16
and said this was a mixed acid-base disorder because according to the Winter's Formula (PaCO2 = 1.5(HCO3-) +8), the PaCO2 is "inappropriately normal and should instead be 32. I can understand this.
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I received a question from a different source that gave me:
pH 7.50
PaCO2 42
HCO3- 35
and called this simply metabolic alkalosis. Using Winter's Formula, the PaCO2 should be 60 but is instead normal.
MY QUESTION: How can you tell if an "inappropriately NORMAL" value is due to a:
1) mixed acid-base disorder, or
2) single acid-base disturbance that has yet to be compensated?
pH 7.23
PaO2 88
PaCO2 40
HCO3- 16
and said this was a mixed acid-base disorder because according to the Winter's Formula (PaCO2 = 1.5(HCO3-) +8), the PaCO2 is "inappropriately normal and should instead be 32. I can understand this.
---
I received a question from a different source that gave me:
pH 7.50
PaCO2 42
HCO3- 35
and called this simply metabolic alkalosis. Using Winter's Formula, the PaCO2 should be 60 but is instead normal.
MY QUESTION: How can you tell if an "inappropriately NORMAL" value is due to a:
1) mixed acid-base disorder, or
2) single acid-base disturbance that has yet to be compensated?
