Blood pressure: (central) venous

Venous pressure

Venous pressure is the blood pressure (BP) in a vein or in the atria of the heart. It is much less than arterial BP, with common values of 5 mmHg in the right atrium and 8 mmHg in the left atrium. Measurement of pressures in the venous system and the pulmonary vessels plays an important role in intensive care medicine but requires invasive techniques.

Central venous pressure

Central venous pressure (CVP) describes the pressure of blood in the thoracic vena cava, near the right atrium. CVP reflects the amount of blood returning to the heart and the ability of the heart to pump the blood into the arterial system. It is a good approximation of right atrial pressure, which is a major determinant of right ventricular end diastolic volume (right ventricular preload).

CVP can be measured by connecting the patient's central venous catheter to a special infusion set which is connected to a small diameter water column. If the water column is calibrated properly the height of the column indicates the CVP.