Blog | Thursday, May 24, 2012

Learning the best way to assess jugular venous pressure

Of all of the physical exam findings that are often taught in medical training, I think one of the most important is the ability to judge volume status from examining neck veins. It's a skill that a lot of medical students and residents strive to become competent in; often many trainees will ask their attendings to verify their findings from their morning rounds.

Finding the level of the jugular venous pressure is hard, but I think it's something that's really worth mastering as it will inform your decision making more so than many other aspects of a daily exam.

To prove my point I ask you, does the quality or quantity of bowel sounds matter in a patient without bowel complaints? Is there any part of the head exam that would change in the course of an inpatient admission? The lung exam may change in a case of pneumonia but isn't the fever curve and the general appearance of the patient better and more important to note? The rales of heart failure may improve in a case of congestive heart failure, but I'd say that when your patient is sleeping flat, no longer dyspneic, and no longer tripoding, the pulmonary finding of rales is irrelevant.

Here is a great website about jugular venous pressure from the University of Washington School of Medicine. Where I got the information at the bottom of this post.

Here is a classic film about the JVP:

I think all of us as internists, hospital and ambulatory, nephrologists and cardiologists should have a good sense of how to find and measure the top of the jugular venous pressure in order to monitor the volume status of our patients on a day-to-day basis. The great challenge in interpreting neck veins, the expert clinician, is to be able to perform wave analysis as Dr. Wood does in this video.

The "a" wave represents the atrial contraction, the x decent represents atrial relaxation, the "v" wave represents ventricular contraction, and the "y" descent represents ventricular diastole.

The most prominent aspects of the neck waves are not the contractions or waves themselves but their troughs: the x and y descent.

Timing of the descents can be done while palpating the carotid or when listening to the heart. The x descent falls into the dub of S2. Lub-clap-dub. The y descent falls during ventricular diastole so it comes after S2. Lub-dub-clap.

Alternatively if you can time the carotid pulse with the x descent by saying C every time you feel the carotid pulse. Then start staying down quickly after every C; C-down, C-down. The x-descent will be occurring as you say down.

Justin Penn, MD, ACP Associate Member, attended medical school at the University of Washington School of Medicine and trained in internal medicine at the University of Rochester, where he is serving as Chief Resident. This post originally appeared at his blog, Musings of an Internist.