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Overview :
The central venous pressure can be estimated from findings
on physical examination.
Patient position: recumbent, with trunk at a 45 degree angle
central venous pressure in cm H2O =
= (vertical height of jugular venous distention above the
sternal angle in cm) + 5 cm
central venous pressure in mm Hg =
= (central venous pressure in cm H2O) / 1.36
where:
• For a 45
degree angle, then the vertical height in cm = (distended length along the
jugular vein ) / SQRT(2).
• 5 cm H2O is 3.65 mm Hg.
Normally the right atrial pressure is 2.5 to 6.0 mm Hg with
a mean of 3.5. At pressures less than 3.7 mm Hg the jugular vein is not
distended; a pressure of 6 mm Hg would show a jugular distention of 3.2 cm.
An elevated central venous pressure may be seen in right
heart failure, constrictive pericarditis and obstruction of the superior vena
cava.
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