Blood gas analysis provides real-time information about the oxygenation, ventilation, and acid-base balance of the critically ill and injured. This book has been prepared for all physicians and healthcare professionals who wish to gain a deeper understanding of blood gas analysis and integrate it into their clinical practice. It covers fundamental physiological principles and provides a detailed examination of conditions such as acidosis, alkalosis, respiratory and metabolic disorders, hypoxemia, and hypercapnia. Additionally, it addresses current topics such as pre- and post-intubation blood gas management, mechanical ventilation optimization, and the role of blood gas analysis in critical patient monitoring. We hope this book will be a valuable resource for all healthcare providers seeking to enhance their knowledge and skills in blood gas analysis.