Central blood volume

Central Blood Volume (CBV) refers to the volume of blood in the heart and the large blood vessels in the thoracic cavity. It is a critical parameter in cardiovascular physiology, as it directly influences cardiac output and blood pressure.

Physiology

The heart and the large blood vessels in the thoracic cavity, including the aorta, pulmonary artery, and vena cava, contain a significant portion of the body's total blood volume. This is referred to as the central blood volume. The CBV is dynamic and can change based on various factors such as body position, physical activity, and hydration status.

The CBV is closely related to the preload of the heart, which is the volume of blood in the ventricles at the end of diastole. An increase in CBV increases the preload, which in turn increases the stroke volume and cardiac output according to the Frank-Starling law of the heart. Conversely, a decrease in CBV decreases the preload, stroke volume, and cardiac output.

Measurement

The measurement of CBV is challenging due to its dynamic nature and the lack of direct measurement techniques. Indirect methods such as echocardiography, magnetic resonance imaging (MRI), and computed tomography (CT) can be used to estimate the CBV. These methods provide images of the heart and the large blood vessels, and the volume of blood can be estimated based on the dimensions of these structures.

Clinical Significance

Changes in CBV can have significant clinical implications. For example, a decrease in CBV can lead to hypotension and shock, while an increase in CBV can lead to hypertension and heart failure. Therefore, maintaining an optimal CBV is crucial in the management of various cardiovascular conditions.

This physiology-related article is a stub. You can help WikiMD by expanding it.