The best measurements for determining blood acid/base health are pH, pCO2, and HCO3-. Reference ranges for these are provided in Table 3. Blood gases are commonly measured on radial or brachial arterial blood.
Table 3. Reference Ranges.
| Reference Range |
| Blood pH | 7.35–7.45 |
| HCO3- | 22–26 mmol/L |
| pCO2 | 35–45 mmHg |
Acidosis occurs when the blood pH is less than 7.35.
Alkalosis occurs when the blood pH is greater than 7.45.
HCO3- represents the "base" portion of the blood.
pCO2 represents the "acid" portion of the blood.
