The jingular venous system is in direct continuity to right atrium in systolic extending to right ventricle in diastole when tricuspid valve is open. In other word its pressure and pattern of pulsation denotes the right sided filling pattern or preload. In absence of any pulmonary or right-sided disease state of l~eart may even be a good indirect indicator of left ventricular preload state.
The pressure and pulsation pattern in internal jugular veins are clinically studied and not that of external jugular system, which takes a sharp bend to enter the subclavian vein which in turn has another bend beibre it drains into SVC. The internal jugular vein unlike its counterpart (external) cannot be seen. The silhouette of skin overlying the internal jugular vein can be studied hence this exarninatidn is always preferable to perfom looking tangentially to root of neck, if necessary again with tangential illumination by a torch.
a)Position of Patient During JVP Examination: Th'e patienl is propped up to 45" on a back rest or pillow as in this position the two waves roll nicely at the root of the neck. In case venous pressure is too high as in severe heart failuse with tricuspid regurgitation patient is made to sit at the edge of the bed with legs hanging to see the height of venous pressure and its pulsation.A nonpulsatiiig very high venous pressure indicative of superior ~nediastinal obstruction.
b) Measurement of Height: Measurement of height of venous pressure is done from the sternal angle of Louis verlically by a ruler in centimeters. Normally it is 4.5 cin or so. If it is too high it is expressed as beyond ear lobes. In case of low venous pressure patient is made to lie flat and abdoniinojugirlar rellux manoeuvre is done. At bedside if a ruler is not available it can be roughly
measured by finger breaths. Roughly at mid phalanx the width is 2 crn in an adult.
c) Venous Pulsation: Nornially the jugular venous pulsation faithf~~lly reflects the pressure changes in rig111 atrium. It is described as a, x, c, x ,v , y, x and x and y being descent and a and v are waves. Tlie 'a' wave is products by atrial contraction and as atrial relaxation sets in x descent begins which is i~iterrupted by a small 'c' wave and ful-ther descent occurs due to downward displacement of atrioventricular ring and ternled as x descent to differentiate it from x dcscent caused by atrial relxation. Tlie 'c' wave is produccd in atrium by the closure of atrioventricular valve but in JVP in neck it is an artifact resulting from systolic thrust of carotid artery, hence named as 'c' by Mclcenzie. As the ventricular contractioil continues the a-v valve remains closed and venous ret~11-11 continues producing another slow undwelling wave called 'v' wave. At the diastole sets in the a-v valve opens producing 'y' descent until diastesis, i.e, equalisation of pressure in atrium and ventricle occurs to be followed by atrial contraction to produce 'a' wave of another cardiac cycle. The x descent is norlnally brisk and easy to identify in JVP. Similarly 'a' wave is brisk event, as caused by active atrial contraction and 'v' is a slow filling wave. In case of difficulty it can be timed with contralateral carotid arlery palpation, 'a' always occurs before carotid pulsation while 'v' wave appears after this.
The pressure and pulsation pattern in internal jugular veins are clinically studied and not that of external jugular system, which takes a sharp bend to enter the subclavian vein which in turn has another bend beibre it drains into SVC. The internal jugular vein unlike its counterpart (external) cannot be seen. The silhouette of skin overlying the internal jugular vein can be studied hence this exarninatidn is always preferable to perfom looking tangentially to root of neck, if necessary again with tangential illumination by a torch.
a)Position of Patient During JVP Examination: Th'e patienl is propped up to 45" on a back rest or pillow as in this position the two waves roll nicely at the root of the neck. In case venous pressure is too high as in severe heart failuse with tricuspid regurgitation patient is made to sit at the edge of the bed with legs hanging to see the height of venous pressure and its pulsation.A nonpulsatiiig very high venous pressure indicative of superior ~nediastinal obstruction.
b) Measurement of Height: Measurement of height of venous pressure is done from the sternal angle of Louis verlically by a ruler in centimeters. Normally it is 4.5 cin or so. If it is too high it is expressed as beyond ear lobes. In case of low venous pressure patient is made to lie flat and abdoniinojugirlar rellux manoeuvre is done. At bedside if a ruler is not available it can be roughly
measured by finger breaths. Roughly at mid phalanx the width is 2 crn in an adult.
c) Venous Pulsation: Nornially the jugular venous pulsation faithf~~lly reflects the pressure changes in rig111 atrium. It is described as a, x, c, x ,v , y, x and x and y being descent and a and v are waves. Tlie 'a' wave is products by atrial contraction and as atrial relaxation sets in x descent begins which is i~iterrupted by a small 'c' wave and ful-ther descent occurs due to downward displacement of atrioventricular ring and ternled as x descent to differentiate it from x dcscent caused by atrial relxation. Tlie 'c' wave is produccd in atrium by the closure of atrioventricular valve but in JVP in neck it is an artifact resulting from systolic thrust of carotid artery, hence named as 'c' by Mclcenzie. As the ventricular contractioil continues the a-v valve remains closed and venous ret~11-11 continues producing another slow undwelling wave called 'v' wave. At the diastole sets in the a-v valve opens producing 'y' descent until diastesis, i.e, equalisation of pressure in atrium and ventricle occurs to be followed by atrial contraction to produce 'a' wave of another cardiac cycle. The x descent is norlnally brisk and easy to identify in JVP. Similarly 'a' wave is brisk event, as caused by active atrial contraction and 'v' is a slow filling wave. In case of difficulty it can be timed with contralateral carotid arlery palpation, 'a' always occurs before carotid pulsation while 'v' wave appears after this.
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| Measurerncnt of the jugular venous pulse - JVP waveforms |
Respiratory Variation: During inspiralion due to fall in intratlioracic pressure the venous pressure goes down (fall in JVP) and reverse happensin expiration.
Analysis and Evaluation of JVP
1) Elevated: Any cause producing right ventricular, failure or in pericardial effusion and in constricitive pericardiitis when promine~~t a' and 'v' waves with sharp x and y descents make M or W pattern.
2) Low JVP: Hypovolaemia, excessive diuresis.
3) Tall 'a' Wave: Forceful atrial contraction as in tricuspid stenosis, atrial rnyxoma.lncreased RV filling pressure - Pulmonary stenosis. Pul. hypertension.
4) Cnnnon 'a' Wave: Atrial contraction during closed a-v valve - complete heart block, 'nodal rhythm premature beat, ventricular pacing.
5) Absent 'a' Wave: Atrial fibrillation, asystole, flutter.6) Elevated 'v' Wave: Tricuspid regurgitation, RV failure, restrictive cardiomyopathy.
7) Prominentx Descent: Tainponade, subacute constriction possibly chronic constriction; RV infarction with preserved atrial contractility.
8) Prominent y Descent: Constrictive pericarditis restrictive cardiomyopathy,tricuspid regurgitation.
9) Slowx Descent: Atrial fibrillation.
10) Slow Descent tamponade tricuspide,stenosis, so called muscle bound RV in TOF.
11) Kussmaul's Sign: Lack or absence of inspiratory decline in venous pressure round in constrictive pericarditis.
12) Spider Waves: Occasionally in atrial flutter rapid sharp waves are seen at the root of neck like a dancing spider.
13) Except in cases of severe tricuspid regurgitation the venous waves are always better seen than palpated.
Analysis and Evaluation of JVP
1) Elevated: Any cause producing right ventricular, failure or in pericardial effusion and in constricitive pericardiitis when promine~~t a' and 'v' waves with sharp x and y descents make M or W pattern.
2) Low JVP: Hypovolaemia, excessive diuresis.
3) Tall 'a' Wave: Forceful atrial contraction as in tricuspid stenosis, atrial rnyxoma.lncreased RV filling pressure - Pulmonary stenosis. Pul. hypertension.
4) Cnnnon 'a' Wave: Atrial contraction during closed a-v valve - complete heart block, 'nodal rhythm premature beat, ventricular pacing.
5) Absent 'a' Wave: Atrial fibrillation, asystole, flutter.6) Elevated 'v' Wave: Tricuspid regurgitation, RV failure, restrictive cardiomyopathy.
7) Prominentx Descent: Tainponade, subacute constriction possibly chronic constriction; RV infarction with preserved atrial contractility.
8) Prominent y Descent: Constrictive pericarditis restrictive cardiomyopathy,tricuspid regurgitation.
9) Slowx Descent: Atrial fibrillation.
10) Slow Descent tamponade tricuspide,stenosis, so called muscle bound RV in TOF.
11) Kussmaul's Sign: Lack or absence of inspiratory decline in venous pressure round in constrictive pericarditis.
12) Spider Waves: Occasionally in atrial flutter rapid sharp waves are seen at the root of neck like a dancing spider.
13) Except in cases of severe tricuspid regurgitation the venous waves are always better seen than palpated.
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| JVP in health and disease |
The term was first coined in 1885 to test the further rise in jugular venous pressure to elicit presence of h;art failures in patients with hepatomegaly and tricuspid regurgitation. It is also known as Abdominal Compression Test.The test is carried out by pressing the right upper quadrant of abdomen with outstretched fingers while lying elevated at 30' on a back rest and slowly increasing the pressure to see the rise of jugular venous pressure 3.4 cm above the basal line.The degree of pressure must not cause any discomfort or pain to the patient as this will vitiate the iat&retation. The raised venous pressure would persist as long as the compression is continued thus unmasking raised systemic venous pressure otherwise unperceived. In normal individuals the jugular venous pressure inay rise transiently to fall to basal level on continued compression of abdominal wall as this will result inco~npression of the inferior vena cava impeding venous return to RA with consequent fall in RA pressure. If right upper quadrant is tender, any part of upper abdominal wall may be compressed. In case of congestive failure both RA and RV are noncoinpliarlt due to over distension compounded by raised sympathetic tone. Rise of venous pressure will continue on compression.
However, false positive rise in venous pressure inay be noted in patients with severe obsiructive pulmonary disease, due to inability to tolerate any further rise in diaphragm, resulting from severe loss of vital capacity. Similarly any increase in blood volume like Polycythaemia Rubra Vera or excessive sympathetic stimulation like nervousness, pain may produce a positive result in absencg of congestive heart failure. In interpretation of positive result one must be careful that increase pulsation should not be inistaken for raised venous pressure. This subtle positive sign nlay alert the attending physician of the possible presence of significant RV infarction complicating a case of inferior infarction.
Blood Pressure
Techrriqrre of Measurement
Following techniques are recommended (JNC VII):
1) Patient should be seated in a chair with their backs supported and their alms bared and supported at heart level.
2) Under special ci~cun~stances,nleasuring BP in supine and standing positioils may be indicated as in to rule out orthostatic hypotension.
3) Patient should refrain from sinoking or ingesting caffeine during the 30 nlin preceding the measurement.
4) Measureme~lt should begin after at least f?ve minutes of rest.
5) Appropriate cuff size must be used to ensure accurate measurement. The bladder within the cuff should encircle at least 80 per , cent of arm.
6) Measurenlent should be taken preferably with a nlcrcury spl~ygmo~nano~neter.
7) Both Systolic Blood Pressure and Diastolic Blood Pressure should be recorded.
The first appearance of sound (Phase I) is used to define SBP aiid the disappearance of sound to define DBP.
8) Two or inore readings separated by two minutes should be averaged if first two readings differ by more that five mmHg, additional readings should be obtained and average.
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Guillelines for Mesurements
Palpatoiy Method: Systolic blood pressure (SBP) can be'n~easured by gradually compressing the brachial artery while palpating the radial artery. The force required to obliterate the radial pulse represents SBP.
Ausultatory Method: The sphygmomanometer cuff is applied around the am1 with its lower edge atleast I inch above the antecubital space. The radial pulse is palpated while the cuff is inflated to pressure of 30 n11nHg above the level at which radial pulsation cannot be felt. The stethoscope (diaphragm) is then placed tightly over the brachial artery aiid the pressure in cuff as lowered 3 mlnHg per second until the first Korotkoff sounds occur. This is the Systolic blood pressure. Continue to lower the pressure until the sounds disappear (5th Korotkoff phase). This is the DBP.Occasionally, the sounds nlay appear first (SBP) then disappear at a point below 200 mn1Hg (Silent gap) and then reappear and finally disappear (DBP). Its significance is unknowil but it may be found in certain patients with hypertension.
Instrmentations: Mercury sphygomenometer is still the most accurate device for clinical use; validated electronic devices or aneroid s~~hyg~noinanorneter may be used for home BP recording.
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