|Author: A. Chandrasekhar, MD||Consultant: R. Lichtenberg, MD and R. Gunnar, MD|
Inspect for internal jugular vein pulsations in the neck, in supine position and with neck and trunk raised to approximate angle of 45o. Internal jugular vein pulsation are visible at the root of the neck between clavicular and sternal heads of sternoclidomastoid muscle. Internal jugular vein corresponds to a line drawn from this point to infra auricular region.
Inspection with simultaneous palpation of the carotid and/or auscultation of the heart will assist in identification and timing of the waves.
Inspect the vein from different angles. Apply light tangentially and observe for venous pulsations in the shadow of neck on the pillow.
At 0o jugular veins should be filled. An impulse visible just prior to S1 or the upstroke of the carotid is the "a-wave". This will be followed by a x-descent. The 'c' wave is usually not visible. The 'v' wave occurs after the start of the carotid upstroke and during ventricular systole (which is atrial diastole). When the tricuspid valve opens there is a brisk descent (y-descent).
Observe the venous pressure changes with respiration. There is normally a drop in intrathoracic pressure with inspiration. This decrease is also reflected on the intracardiac pressures. Therefore, an increase in the pressure difference between the SVC/IVC and the RA increases cardiac filling.