Classification of Acid-Base Abnormalities
There are 4 basic acid-base disturbances (Fig. 6.4):
- Metabolic acidosis
- Metabolic alkalosis
- Respiratory acidosis
- Respiratory alkalosis
All 4 can be uncompensated, partially compensated, or compensated; overcompensation does not occur. If the primary disturbance is respiratory (abnormal pCO2), compensation will be metabolic (through the kidneys) and vice versa. The respiratory and renal systems are, of course, both metabolic, but for the purposes of describing acid-base disturbances, the respiratory system is considered separately from other metabolic systems.
Table 6.3 demonstrates the expected changes in values seen on the blood gas and biochemical panel results for the four major acid-base disturbances.