Jugular venous distension

The jugular venous pressure (JVP, sometimes referred to as jugular venous pulse) is the indirectly observed pressure over the venous system via visualization of the internal jugular vein. It can be useful in the differentiation of different forms of heart and lung disease. Classically three upward deflections and two downward deflections have been described.

The patient is positioned at a 45° incline, and the filling level of the external jugular vein determined. Visualize the internal jugular vein when looking for the pulsation. In healthy people, the filling level of the jugular vein should be less than 3 centimetres vertical height above the sternal angle. A pen-light can aid in discerning the jugular filling level by providing tangential light.

The JVP is easiest to observe if one looks along the surface of the sternocleidomastoid muscle, as it is easier to appreciate the movement relative to the neck when looking from the side (as opposed to looking at the surface at a 90 degree angle). Like judging the movement of an automobile from a distance, it is easier to see the movement of an automobile when it is crossing one's path at 90 degrees (i.e., moving left to right or right to left), as opposed to coming toward one.

Pulses in the JVP are rather hard to observe, but trained cardiologists do try to discern these as signs of the state of the right atrium.

The JVP and carotid pulse can be differentiated several ways:

The jugular venous pulsation has a biphasic waveform.

A classical method for quantifying the JVP was described by Borst & Molhuysen in 1952. It has since been modified in various ways. A venous arch may be used to measure the JVP more accurately.

Moodley's Sign This sign is used to determine which waveform you are viewing. Feel the radial pulse while simultaneously watching the JVP. The waveform that is seen immediately after the arterial pulsation is felt is the 'v wave' of the JVP.

The term hepatojugular reflux was previously used as it was thought that compression of the liver resulted in "reflux" of blood out the hepatic sinusoids into the great veins thereby elevating right atrial pressure and visualized as jugular venous distention. The exact physiologic mechanism of jugular venous distention with a positive test is much more complex and the commonly accepted term is now "Abdominojugular test."

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