What is the relationship between cardiac output and oxygen delivery?

The relationship between cardiac output and oxygen delivery is directly proportional. Cardiac output, which is the volume of blood the heart pumps per minute, plays a crucial role in determining the amount of oxygen delivered to the tissues.

Oxygen delivery (DO2) can be expressed using the formula: DO2 = Cardiac Output (CO) × Arterial Oxygen Content (CaO2). This means that as cardiac output increases, assuming the arterial oxygen content remains constant, the overall oxygen delivery to the tissues also increases. Conversely, if cardiac output decreases, oxygen delivery will also decrease.

This relationship underlines the importance of maintaining adequate cardiac output, especially in critical care settings where patients may be reliant on interventions like ECMO to support or restore normal cardiac function and enable sufficient oxygen delivery.

In cases where cardiac output is compromised, tissues risk becoming hypoxic, emphasizing the necessity of closely monitoring and managing cardiac output in various clinical scenarios.