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The Jugular Venous Pressure and Pulse
Dr Nighat Majeed
Assistant Professor
Medical Unit II
SIMS/SHL Lahore
Introduction It provides indirect measure of central
venous pressure. The normal mean jugular venous pressure,
determined as the vertical distance above the midpoint of the right atrium, is 6 to 8 cm H2O.
Deviations from this normal range reflect
Hypovolemia ( less than 5 cm H2O).
Impaired cardiac filling(greater than9cm).
Introduction The peripheral venous pressure is
measured accurately with manometry. For clinical purposes, approximation of
venous pressure can be obtained by inspection of jugular pulsations.
An elevated JVP is the classic sign of venous hypertension (e.g. right-sided heart failure).
Introduction
JVP elevation can be visualized as jugular venous distension, whereby the JVP is visualized at a level of the neck that is higher than normal.
Reference point for bed side evaluation is sternal angle.
Basic Physiology The right internal jugular vein
communicates directly with the right atrium via the superior vena cava.
There is a functional valve at the junction of the internal jugular vein and the superior vena cava.
This valve does not impede the phasic flow of blood to the right atrium. Thus the wave form generated by phasic flow to the right atrium is accurately reflected in the internal jugular vein.
Basic Physiology The external jugular vein possesses valves. The relatively direct line between the right
external and internal jugular veins, as compared to the left external and internal jugular veins, make the right jugular vein the preferred system for assessing the venous pressure and pulse contour.
Basic Physiology In determining mean jugular venous
pressure, one assumes that the filling pressure of the right atrium and right ventricle are the mirror that of the left atrium and left ventricle.
This relationship is usually correct.
Exceptions
correlate with history and physical examination
Acute left ventricular failure may significantly raise the pulmonary capillary wedge pressure without raising the mean right atrial and jugular venous pressures.
pulmonary hypertension, tricuspid insufficiency, or stenosis may be associated with elevated mean right atrial and jugular venous pressures while leaving the left heart pressures unaffected.
Clinical Examination The patient is positioned under 45°, and
the filling level of the 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 a maximum of (3-4) centimeters above the sternal angle.
Visualization Height of jugular pulsations varies with the
position of chest. The upper limits for normal venous pressures are recumbent,2cm 30 degrees,3cm 45 degrees,4.5cm Upright at the level of suprasternal notch. these values are less than those obtained
by manometry because the true zero is at the level of right atrium.
Characteristics of JVP Multiphasic The JVP "beats" twice (in quick succession) in
the cardiac cycle. The first beat represents that atrial
contraction (termed a). second beat represents venous filling of the
right atrium against a closed tricuspid valve (termed v) and not the commonly mistaken 'ventricular contraction'.
The carotid artery only has one beat in the cardiac cycle
Characteristics of JVP Non-palpable - the JVP cannot be
palpated. If one feels a pulse in the neck, it is
generally the common carotid artery.
Characteristics of JVP Occludable The JVP can be stopped by occluding
the internal jugular vein by lightly pressing against the neck.
varies with head-up-tilt (HUT) The JVP varies with the angle of neck.
The carotid pulse's location does not vary with HUT.
Characteristics of JVP
varies with respiration - the JVP usually decreases with deep inspiration. Physiologically, this is a consequence of the Frank-Starling mechanism as inspiration decreases the thoracic pressure and venous return.
The jugular venous pressure (JVP)
Waveforms of the JVP a - presystolic; produced by right atrial
contraction. c - bulging of tricuspid valve into the
right atrium during ventricular systole (isovolumic contraction phase).
v - occurs in late systole; (atrial venous filling)increased blood in right atrium from venous return.
Descents(occur during diastole)
x - combination of atrial relaxation, downward movement of the tricuspid valve and ventricular systole Deeper than the y descent).
y - tricuspid valve opens and blood flows in to the right ventricle.
Descents(occur during diastole)
Usually, the descents in the jugular venous pulse are brisk but not excessively rapid.
The descents or troughs of the jugular venous pulse occur between the "a" and "c" wave ("x" descent), between the "c" and "v" wave ("x" descent), and between the "v" and "a" wave ("y" descent).
How to examine the JVP
• Use the right internal jugular vein. • Neck should not be sharply flexed.
• Patient should be at a 45° angle.
• Head turned slightly to the left. • If possible have a tangential light
source that shines obliquely from the left.
How to examine the JVP(contd)
• Locate the surface markings of the internal jugular vein runs from medial end of clavicle to the ear lobe under medial aspect of the sternocleidomastoid.
• Locate the JVP - look for the double waveform pulsation (palpating the contralateral carotid pulse will help).
How to examine the JVP Measure elevation of neck veins above
the sternal angle (Lewis Method). Using a centimeter ruler, measure the
vertical distance between the angle of Louis (manubrio sternal joint) and the highest level of jugular vein pulsation. A straight edge intersecting the ruler at a right angle may be helpful.
How to examine the JVP(contd)
• Measure the level of the JVP by measuring the vertical distance between the sternal angle and the top of the JVP. Measure the height - usually less than 3cm
How to examine the JVP(contd)
Add 5 cm to measurement since right atrium is 5 cm below the sternal angle.
Normal CVP <= 8 cm H2O
How to examine the JVP(contd) If the internal jugular vein is not
detectable, use the external jugular vein. The internal jugular vein is the preferred site.
Thus, either the external or internal jugular vein may be useful in the assessment of mean venous pressure and pulse contour.
Wave Form
The a and v wave can be identified by timing the double waveform with the opposite carotid pulse.
The a wave will occur just before the pulse and the v wave occurs towards the end of the pulse.
Wave Form
Distinguishing the c wave, x and y descents is an almost impossible task.
Differentiate a jugular venous pulse from the carotid pulse
The JVP pulse is Not palpable. Obliterated by pressure. Characterised by a double waveform. Varies with respiration - decreases with
inspiration. Enhanced by the hepatojugular reflux.
Jugular Vein Carotid Artery
No pulsations palpable Palpable pulsations
Pulsations obliterated by pressure above the clavicle.
Pulsations not obliterated by pressure above the clavicle.
Level of pulse wave decreased on inspiration; increased on expiration
No effects of respiration on pulse.
Usually two pulsations per systole (x and y descents).
One pulsation per systole.
Prominent descents Descents not prominent.
Pulsations sometimes more prominent with abdominal pressure.
No effect of abdominal pressure on pulsations.
Hepatojugular reflux (abdominojugular reflux sign)
This can help confirm that the pulsation is caused by the JVP.
Firm pressure is applied to the right upper quadrant using the palm of the hand.
A transient increase in the JVP will be seen in normal patients.
There may be a delayed recovery back to baseline which is more marked in right ventricular failure.
Causes of a raised JVP Heart failure. In constrictive pericarditis. restrictive cardiomyopathy. pericardial effusion. Right-sided heart failure. JVP increases on inspiration called
Kussmaul's sign Cardiac tamponade. Fluid overload e.g. renal disease. Superior vena cava obstruction (no pulsation).
Abnormalities of the JVP Abnormalities of the a wave Disappears in atrial fibrillation. Large a waves Right ventricular hypertrophy (pulmonary
hypertension and pulmonary stenosis) Decreased right ventricular compliance as in
restrictive cardiomyopathy. Tricuspid stenosis. Extra large a waves (called cannon
waves) complete heart block ventricular tachycardia.
Prominent v waves
Tricuspid regurgitation called cv or V waves and occur at the
same time as systole (combination of v wave and loss of x descent), there may be ear lobe movement.
Slow y descent
Tricuspid stenosis. Right atrial myxoma.
Steep y descent
Right ventricular failure. Constrictive pericarditis. Tricuspid regurgitation. (The last two conditions have a rapid
rise and fall of the JVP called Friedreich's sign).
Prognostic use of the JVP
An elevated JVP in patients with heart failure is associated with an increased risk of hospital admission, death and subsequent hospitalization for heart failure. Therefore appreciation of this sign can be clinically helpful.
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