2003 Volume 14 Issue 4 Pages 291-295
The purpose of the study was to assess venous-valve movement and venous flow in the lower extremity in connection with respiration. We performed ultrasonographic study of right lower limb in 10 healthy male volunteers. Each subject was placed supine in reverse-Trendelenburg’s position and respiration was monitored during examination. In each examination, both abdominal respiratory method (using diaphragm movement; AbM) and thoracic respiratory method (using thoracic enlargement; ThM) were performed. The valve movement and the blood flow in the right femoral vein were analyzed by B-mode and pulse Doppler images, respectively, in connection with respiratory methods. Usually, the valve was observed to open and close at the start of expiration and inspiration, respectively, and the flow has been observed during expiration when AbM was used (9/10). When ThM was used, no closure of the valve was observed and the flow has been observed without apparent pause in most cases (6/10, P<0.05). The effect of respiration on the valve movement and the venous flow was considered to be significant. The flow pattern may largely depend on the respiratory method and expiration may have an effect to accelerate the venous flow in some degree when AbM is used.
