How did you arrive at your answer?
You needed to think through what the normal values are that you are expecting in the result and decide on whether these are OK, high or low before interpreting the result.
You needed to identify that the pH is low indicating an acidosis, the CO2 (respiratory component) is normal albeit at the bottom end of the range and that the bicarbonate level (metabolic component) is also low.
The gas shows an uncompensated metabolic acidosis. In addition, the oxygen level is on the low side of normal and the lactate is high, so you should have identified the result as:
Metabolic Acidosis with a high lactate level.
Blood Gas Result
Arterial Sample
Time: 18:30
| pH | 7.2 |
| pCO2 | 3.5 kPa |
| pO2 | 10 kPa |
| HCO3 | 16 mmols/L |
| Lactate | 4.1 mmols/L |
Normal Values
| pH | 7.35-7.45 |
| pCO2 | 3.5-5.0 kPa |
| pO2 | 10.6-13.3 kPa |
| HCO3 | 24-32 mmols/L |
| Lactate | 0.5-1.6 mmols/L |


