Comparison of single- and two-channel neuromuscular electrical stimulation sites for enhancing venous return.

Neuromuscular electrical stimulation (NMES) has previously been used to activate the musculature of the lower leg and increase venous return to the heart. However, there is little evidence to suggest the superiority of one particular stimulation site over another. In this paper, we aim to reveal the optimal stimulation site on the lower leg in a group of healthy adults.

Doppler ultrasound measurements of venous return in the popliteal vein.

An assessment of the use of Doppler ultrasound for the measurement of venous blood expelled at the site of the popliteal vein was made. Ten subjects underwent colour Doppler ultrasonography and measurements for peak venous velocities and venous blood volume expelled were taken for each subject when standing and during voluntary contractions. The study shows that only a weak correlation exists between peak venous velocities and venous blood volume expelled, indicating that peak venous velocity alone, is not an accurate measure of the performance of the calf muscle pump either naturally or via artificial means.