Arterial Blood Gas Analysis

Authors: Gillian Kelly / Editor: Jason M Kendall / Reviewer: Michael Perry, Josh Davison, Jia Luen Goh / Code: A2, PP2, R1, R2 / Published: 19/07/2021 / Reviewed: 16/04/2026

This module focuses on the evaluation of arterial blood gases in the emergency department (ED).

After completing this session you will be able to:

• Explain acid-base balance and the principles of physiological buffering
• Describe the different types of acid-base derangement and their effects on the oxyhaemoglobin dissociation curve
• List the causes of acid-base derangement including problems which affect the oxygen carrying capacity of the blood
• Describe the compensatory mechanisms of acid-base derangement
• Interpret an arterial blood gas assay

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