In this module, we will discuss hypoxia and cyanosis. You will learn the difference between hypoxia and cyanosis, as well as the causes of both central and peripheral cyanosis, which include congenital anomalies, anatomical shunts, and physiological shunts. You will learn how to properly analyze the oxygen dissociation curve and the alveolar-arterial gradient. Lastly, you will learn how to manage patients with hypoxia and cyanosis and gain an understanding about the proper use of oxygen therapy.