Arterial Blood Gas (ABG) Interpretation

A set of flashcards focused on normal laboratory values, compensatory mechanisms, and the steps for interpreting Arterial Blood Gas results.

Normal pH range

$$7.35–7.45$$

Normal $CO2$ range

$$35–45\,mmHg$$

Normal $HCO3$ range

$$22–26\,mEq/L$$

Lungs (ABG role)

Opposing system that controls the $CO2$ level as a respiratory compensatory mechanism.

Kidneys (ABG role)

Opposing system that controls the $HCO3$ level as a metabolic compensatory mechanism.

Carbon dioxide ($CO2$) effect

Makes the blood more acidic and decreases blood pH.

Bicarbonate ($HCO3$) effect

Makes the blood more basic and increases blood pH.

pH High label

Alkaline

$CO2$ High label

Acidic

$HCO3$ High label

Alkaline

Step 4 of ABG interpretation

Match the pH label with $HCO3$ or $CO2$ and determine the system at fault.

Uncompensated

The opposing system is in the normal range and the pH is not in the normal range.

Partially compensated

The opposing system is not in the normal range and the pH is not in moving into the normal range.

Fully compensated

The opposing system is not in the normal range and the pH is in the normal range.

Kussmaul breathing

Deep, rapid breathing that serves as the lung’s way of responding to extreme acidosis by blowing off $CO2$.