Spontaneous variations in venous tone in man

¹ Department of Medicine, Tulane University School of Medicine; and Charity Hospital of Louisiana, New Orleans, Louisiana

Using the intact isolated venous segment technique, Statham strain-gauge pressure transducers and a multichannel direct recorder, spontaneous changes in venous tone were recorded in human subjects with and without congestive heart failure. Evidence was presented to show the existence of spontaneous variations in venous tone. Specific venous pressure deflections were described similar to, if not identical with, the alpha and beta deflections described in digital plethysmography. Venous pressure deflections associated with respiration and with transmitted arterial pulsations were also described. The effect of Cheyne-Stokes respiration on systemic venous pressure was observed fortuitously in one subject. It was noted that during sleep venous pressure usually decreased but occasionally increased. This increase is probably associated with dreams or other disturbances. Spontaneous venomotor changes were found equally in subjects with and those without congestive heart failure.