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The Jugular Venous Pressure Revisited

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The Jugular Venous Pressure Revisited REVIEW CME EDUCATIONAL OBJECTIVE: Readers will measure and interpret the jugular venous pressure in their patients CREDIT with heart failure JOHN MICHAEL S. CHUA CHIACO, MD NISHA I. PARIKH, MD, MPH DAVID J. FERGUSSON, MD Cardiovascular Disease, John A. Burns School Assistant Professor, John A. Burns School Clinical Professor of Medicine, Department of Medicine, University of Hawaii, Honolulu of Medicine, University of Hawaii; of Cardiology, John A. Burns School The Queen’s Medical Center, Honolulu of Medicine, University of Hawaii; The Queen’s Medical Center, Honolulu The jugular venous pressure revisited ■■ ABSTRACT n this age of technological marvels, I it is easy to become so reliant on them as Assessment of the jugular venous pressure is often inad- to neglect the value of bedside physical signs. equately performed and undervalued. Here, we review Yet these signs provide information that adds the physiologic and anatomic basis for the jugular venous no cost, is immediately available, and can be pressure, including the discrepancy between right atrial repeated at will. and central venous pressures. We also describe the cor- Few physical findings are as useful but as rect method of evaluating this clinical finding and review undervalued as is the estimation of the jugular the clinical relevance of the jugular venous pressure, venous pressure. Unfortunately, many practi- especially its value in assessing the severity and response tioners at many levels of seniority and experi- to treatment of congestive heart failure. Waveforms ence do not measure it correctly, leading to a vicious circle of unreliable information, lack reflective of specific conditions are also discussed. of confidence, and underuse. Another reason ■■ KEY POINTS for its underuse is that the jugular venous pres- sure does not correlate precisely with the right If the jugular venous pressure differs from the true right atrial pressure, as we will see below. atrial pressure, the jugular venous pressure is always the In this review, we will attempt to clarify lower value. physiologic principles and describe technical details. Much of this is simple but, as always, the devil is in the details. The jugular venous pressure is useful to observe when diagnosing congestive heart failure and when consider- ■ ANATOMIC CONSIDERATIONS ing the need for or the adequacy of diuresis. Think of the systemic veins as a soft-walled The jugular venous wave form is more difficult to observe and mildly distensible reservoir with finger- than its elevation but can yield useful information in the like projections, analogous to a partially fluid- 1 assessment of certain arrhythmias, right-heart conditions, filled surgical glove. In a semi-upright posi- and pericardial disease. tion, the venous system is partially filled with blood and is collapsed above the level that this blood reaches up to. Blood is constantly flowing in and out of this reservoir, flowing in by venous return and flowing out by the pumping action of the right side of the heart. The volume in the venous reservoir and hence the pressure are normally maintained by the variability of right ventricular stroke volume in accor- dance with the Frank-Starling law. Excess volume and pressure indicate failure of this homeostatic mechanism. The internal jugular veins, being con- doi:10.3949/ccjm.80a.13039 tinuous with the superior vena cava, provide 638 CLEVELAND CLINIC JOURNAL OF MEDICINE VOLUME 80 • NUMBER 10 OCTOBER 2013 Downloaded from www.ccjm.org on October 1, 2021. For personal use only. All other uses require permission. CHUA CHIACO AND COLLEAGUES a visible measure of the degree to which the lower venous pressures. systemic venous reservoir is filled, a manom- This indicates the following: eter that reflects the pressure in the right • In the presence of congestive heart failure, atrium—at least in theory.2 Thus, the vertical the right atrial pressure is at least as high height above the right atrium to which they and perhaps higher than the jugular ve- are distended and above which they are in a nous pressure. Hence, if the jugular venous collapsed state should reflect the right atrial pressure is high, further treatment, espe- pressure. cially diuresis, is needed. (In fact, the jugular venous pressure may • A jugular venous pressure of zero implies a underestimate the right atrial pressure, for euvolemic state. reasons still not understood. This will be dis- Thus, the jugular venous pressure provides cussed below.) excellent guidance when administering diure- In a healthy person, the visible jugular sis in congestive heart failure. These deduc- veins are fully collapsed when the person is tions obviously require the clinical judgment standing and are often distended to a variable that the elevated right atrial pressure and degree when the person is supine. Selecting an jugular venous pressure do indeed reflect el- appropriate intermediate position permits the evation of pulmonary capillary wedge pressure top of the column (the meniscus) to become rather than other conditions discussed later in visible in the neck between the clavicle and this article. the mandible. ■ WHICH REFERENCE POINT TO USE? ■ DISCREPANCY BETWEEN JUGULAR VENOUS AND RIGHT ATRIAL PRESSURE The two points that can be used as refer- ences above which the jugular venous pres- Several reports have indicated that the jugu- sure is expressed are the center of the right lar venous pressure may underestimate the atrium and the sternal angle. While the right atrial pressure. Deol et al3 confirmed former may reflect physiology, the latter is this, while establishing an excellent correla- preferred, as it is always visible and has the The internal tion between the level of venous collapse (ob- added advantage of being close to the upper jugular veins served on ultrasonography) and the jugular limit of normal, which is about 3 cm above venous pressure. The difference between the this level. act as a right atrial pressure and the jugular venous The difference in height between these manometer, pressure tended to be greater at higher venous two reference points has often been quoted reflecting pressures.3 as 5 cm, but this is an underestimate in the Most people have a valve near the termi- body positions used in examination.5 Seth the pressure nation of the internal jugular vein, with vari- et al6 found a mean of 8 cm at 30° elevation, in the right able competence. Inhibition of reflux of blood 9.7 cm at 45°, and 9.8 cm at 60°. The dif- from the superior vena cava into the internal ference also varied between patients, being atrium— jugular vein by this valve is the most plausible larger in association with smoking, older with a notable cause of this disparity.4 age, large body mass index, and large anteri- The failure of the jugular venous pressure or-posterior diameter. These factors should qualification to correlate with the right atrial pressure has be considered when trying to evaluate the been cited by some as a reason to doubt the significance of a particular jugular venous value of a sign that cardiologists have long pressure. relied on. How do we reconcile this apparent The junction of the midaxillary line and paradox? Careful review of the literature that the fourth left intercostal space (“the phlebo- has demonstrated this lack of correlation re- static point”) has been recommended as a ref- veals the following: erence point by some, as it is level with the • When unequal, the jugular venous pres- mid-right atrium. However, using the phlebo- sure always underestimates the right atrial static point as a reference position is cumber- pressure. some and results in a valid measurement only • The lack of correlation is less evident at with the patient in the supine position.7 CLEVELAND CLINIC JOURNAL OF MEDICINE VOLUME 80 • NUMBER 10 OCTOBER 2013 639 Downloaded from www.ccjm.org on October 1, 2021. For personal use only. All other uses require permission. JUGULAR VENOUS PRESSURE ■ The jugular venous pressure examination The patient lies comfortably at an angle that brings the pulsating column into view. The head lies on the pillow with the shoulders on the mattress, relaxing the sternocleidomastoid. The heel of the examiner’s left palm gently adjusts head rotation and angulation. The flashlight held in the right Once the meniscus has been located, hand shines tangentially to its anatomic site is noted and its height the skin against a darkened above the sternal angle is measured background. using a ruler held vertically and a pen held horizontally to that site. CCF Medical Illustrator: Beth Halasz ©2013 FIGURE 1 ■ TECHNIQUE IS VITAL • Turning the head away and elevating the jaw, both slightly; this is often best achieved Close adherence to technical details is vital in by gentle pressure of the palm of the observ- reliably and reproducibly measuring the pres- er's hand on the patient's forehead. sure in the internal jugular veins (FIGURE 1). The right side is usually observed first, as Degree of head elevation it is the side on which the examiner usually Although the proper degree of head eleva- stands. Using the right side also avoids the tion is sometimes said to be between 30° rare occurrence of external compression of the and 60°, these numbers are approximate. left brachiocephalic vein. The correct angle is that which brings the venous meniscus into the window of vis- Head and shoulders ibility in the neck between the clavicle and The sternocleidomastoid muscle lies anterior mandible. to each internal jugular vein.8 When tense, it impedes good observation. Shortening, and Lighting hence relaxing, this muscle permits the me- Shining a flashlight tangentially to the skin is niscus to be observed. Correct positioning is often helpful, casting shadows that improve achieved by: the visibility of vein motion. Dimming the • Placing a folded pillow behind the pa- room lighting may further enhance this effect.
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