Ultrasound measurement of internal jugular vein distention could help diagnosing heart failure in the immediate care setting. A study in Am J Emerg Med Nov 2011 suggests a sensitivity of 100% and a specificity of 59% when compared to C-ECHO. There is a significant amount of false positives but JVD-US seems to reliably rule out CHF. Perhaps, maybe, helpful, especially in the very sick patients who really don´t have time to wait for an C-ECHO, Chest-X or proBNP.
They enrolled patients with dyspnea. Patients where heart failure wasn’t considered as a diagnosis were excluded from the study. So this was already a selected population. Still, the method gives some interesting insight into the physiology of CVP, ultrasound and heart failure. And it might be a tool among many to help you differentiate?
How to do it
The right internal jugular vein is a direct conduit to the right heart. With the right atrium as zero-point, the column of blood in the jugular vein and can be viewed as a barometer. The top of that barometer’s column is the level of the jugular vein where pulsations can be seen and where it collapses because of atmospheric pressure.
If filling pressures are high, the jugular vein will be distended all the way into the head and no pulsations will be visible. If filling pressures are low, the jugular vein will collapse from the atmospheric pressure and no pulsations will be visible.
In the 45 degree position there’s normally 5cm from the right atrium to the sternal notch, so in patients with a CVP of more than 5 cmH20 the pulse meniscus will be visible above the sternal notch. A normal jugular venous pressure is < 8 cm H2O (venous pulse less than 3 cm above sternal angle) Abnormal values are > 8 cmH20.
In this study the US is used to identify the level of the pulsations and vessel collapse of the internal jugular vein instead of relying on visual identification of the external jugular vein.
Visual identification of the meniscus of the external jugular vein is of course the old Lewis method of determining elevated venous filling pressures. The Lewis method can be difficult to do, and has low a sensitivity in the 50% range.
Hope this makes sense?
ThomasD: This is just a non-invasive way of measuring the CVP? And is that useful? Maybe. As the study concludes: JVD-US may help guide the clinician to administer the most appropriate medications to the challenging acute patient with rales and hypotension: if the JVD-US is less than 8, then administer intravenous fluid rather than diuretics and vasodilators, as CHF would essentially be ruled out.
Jang T, Aubin C, Naunheim R, Lewis LM, Kaji AH. Jugular venous distension on ultrasound: sensitivity and specificity for heart failure in patients with dyspnea. Am J Emerg Med. 2011 Nov;29(9):1198-202. Epub 2010 Oct 15.