Master Acid-Base Balance & ABG Interpretation 2026 – Ace the Test and Balance Your Success!

PaCO2 shows how well the lungs are regulating ventilation. When it falls within the normal range (about 35–45 mmHg), it means the respiratory system is not driving an acid-base problem—there’s no primary respiratory issue contributing to the imbalance. To identify a metabolic problem, you’d look at bicarbonate (HCO3−) and pH rather than PaCO2. So a normal PaCO2 indicates no respiratory cause; metabolic disturbances would be diagnosed from the other ABG parameters, not from PaCO2 alone.