cardiacoutput

Cardiac output (CO) is a fundamental physiological measurement representing the volume of blood the heart pumps per minute. It is a key indicator of the heart's efficiency and the body's ability to supply oxygen and nutrients to its tissues. Cardiac output is calculated by multiplying the heart rate (HR), which is the number of times the heart beats per minute, by the stroke volume (SV), which is the amount of blood ejected from the left ventricle with each beat. The formula is CO = HR x SV.

Factors influencing cardiac output are numerous and interconnected. Heart rate can increase or decrease in response to physiological demands such as exercise, stress, or rest. Stroke volume is affected by preload, which is the amount of blood filling the ventricles before contraction, afterload, which is the resistance the ventricles must overcome to eject blood, and contractility, the inherent strength of the heart muscle's contraction.

Normal resting cardiac output in an adult typically ranges from 4 to 8 liters per minute. During strenuous exercise, this value can increase significantly to meet the heightened metabolic demands of the body. Conversely, conditions that impair heart function, such as heart failure or significant blood loss, can lead to a reduced cardiac output, potentially causing symptoms like fatigue, shortness of breath, and organ dysfunction. Monitoring and understanding cardiac output are crucial in diagnosing and managing a wide spectrum of cardiovascular conditions.