Arterial Blood Gas (ABGs) Tic-Tac-Toe

HCO3

22-26 (above 26 alkalosis), (Below 22 acidic)

PaCO2 (mm Hg)

35-45 (below 35 alkalosis), (above 45 acidosis)

Metabolic

HCO3 and pH

Respiratory

PaCO2 and pH

Compensation

involves opposites: for example, in primary metabolic acidosis, compensation involves respiratory alkalosis; in primary respiratory acidosis, compensation involves metabolic alkalosis

Arterial Blood Gas

laboratory tests commonly used to determine the adequacy of oxygenation and ventilation, as well as in the assessment and treatment of acid-base imbalance

Complete compensation

occurs when the body's ability to compensate is so effective that the pH falls within the normal range.

pH levels

pH 7.35-7.45

Partial compensation

some compensation occurs but pH remains abnormal

Metabolic alkalosis

↑ pH >7.45 ↑ HCO3− Normal PaCO2

Respiratory alkalosis

↑ pH >7.45 ↓ PaCO2 Normal HCO3−

Respiratory acidosis

↓ pH <7.35 ↑ PaCO2 Normal HCO3−

Metabolic acidosis

↓ pH <7.35 ↓ HCO3− Normal PaCO2