Abstract
There is little information available on the role of the upper-extremity muscle pump in venous outflow and there is no standard method for evaluation of the venous pump function in upper extremities. Also, the role of contractions of forearm and arm muscles in augmentation of venous outflow remains unclear. The aim of this study was to evaluate the muscular venous pump in the upper extremity with photoplethysmography. Venous photoplethysmography of the upper limb was performed in 30 healthy subjects randomly divided into 2 groups for the evaluation of forearm (group I) and arm (group II) muscles separately. In the group I average values of Vp (venous pump index) in the right limb were 8.3 and in the left limb 11.1. In group II Vp was 36.1 and 36.7, respectively. In the group I average values of RT (venous return time) in the right limb were 3.4 and in the left limb 5.9 s. In the group II RT was 24.8 and 30.9 s, respectively. Differences of Vp and RT were statistically significant between group I and group II (p = 0.001). There were no statistically significant differences of Vp and RT between right and left limbs in both groups. We conclude that arm muscle contractions augment venous outflow from the upper extremity, while forearm muscle contractions do not significantly increase venous flow and do not serve as a muscle pump for venous system in the upper extremities.
