What formula is used to calculate cardiac output?

The correct choice is based on the understanding that cardiac output is defined as the amount of blood the heart pumps in one minute. This quantity is determined by two key factors: the stroke volume, which is the amount of blood ejected by the heart during each heartbeat, and the heart rate, which is the number of beats per minute.

To calculate cardiac output, one multiplies the stroke volume by the heart rate. This formula reflects the principle that if the heart pumps a greater volume of blood with each beat or beats more frequently, the overall output of blood distributed throughout the body increases accordingly. Therefore, if stroke volume is high or the heart rate is elevated, cardiac output increases, indicating effective perfusion to vital organs and tissues.

Using this formula is essential in clinical settings for assessing a patient's cardiovascular status and guiding treatment decisions, particularly in conditions such as heart failure or shock, where maintaining adequate cardiac output is crucial for patient stability.