This document provides an overview of arterial blood gas (ABG) testing. It defines an ABG test as measuring oxygen, carbon dioxide, pH and other values in arterial blood. The document outlines the normal ranges measured and details the procedure for drawing arterial blood, including using a syringe to extract blood from the radial artery. It explains that ABG tests are important for monitoring critically ill or respiratory patients. The document concludes by discussing how to interpret different results based on changes in pH, carbon dioxide and bicarbonate levels.