Blood Gas of the Week #13
A 4 year, castrated male Husky is presented for acute onset bloody diarrhea about 48 hours after getting into the garbage. He otherwise seems fine: still active, eating, and drinking. His physical examination is consistent with mild dehydration but otherwise is unremarkable.
T 102.2F P 100 R 27 mm pink CRT 1.5s BCS 5/9 Weight 27kg BP 127/86 (100mmHg)
Interpret the blood gas:
Step 1: Evaluate the pH
The patient’s pH is 7.36 – this is in the normal range. There are two possibilities when we see a normal pH:
- The patient’s acid-base status is normal OR
- The patient has a mixed acid-base status
The biggest mistake that people make is looking only at the pH, and stopping when they see it is normal. When you do this, you will miss many mixed disturbances that could give you clues about what is going on with the patient.
Step 2: Evaluate the pCO2, and the bicarbonate
The pCO2 is 36 – this in the normal range
The bicarbonate is 18 – also in the normal range
So, the pH, bicarbonate, and the pCO2 are all in the normal range. This patient has a
Want to learn about reading blood gases? You’ve come to the right place. Every week a new blood gas case will be posted. The scenario will post on Monday and the solution will post on Wednesday.
New to blood gasses? Check out the quick guide to acid-base interpretation here.
