Doppler ultrasound demonstrated good agreement and consistency between two days of testing for measuring popliteal blood flow and vascular conductance at rest and exercise.
We tested the data repeatability for popliteal blood flow velocity (PBV), popliteal arterial diameter (AD(pop)), popliteal blood flow (PBF) and lower limb vascular conductance (VC) at rest and exercise in three body positions, two work rates and two inspired oxygen fractions. Fifteen, eleven and ten healthy volunteers participated in the three phases of the studies. Resting protocols were performed in horizontal (HOR), 35° head-down tilt (HDT) and 45° head-up tilt (HUT) for 5 min in each body position. Participants also exercised at lower and higher power outputs (repeated plantar flexion contractions at 20% and 30% maximal voluntary contraction, respectively) in HOR, HDT and HUT and in normoxia (21%O2) and hypoxia (14%O2) with the same work rates and body positions. PBV and AD(pop) were measured by ultrasound to determine PBF, and VC was estimated by dividing PBF by muscle perfusion pressure (MPP). PBV, AD(pop), PBF and VC were not different, demonstrated good agreement and consistency between the two days of testing during both rest and exercise conditions regardless of body position. Therefore, these data support the utilization of Doppler and echo Doppler ultrasound as a reproducible method to measure PBV and AD(pop) and consequently estimate PBF and VC responses in such conditions.
Villar et al. (Tue,) conducted a other in Healthy volunteers (n=15). Doppler ultrasound measurement vs. Between two days of testing was evaluated on Repeatability of popliteal blood flow velocity, arterial diameter, blood flow, and vascular conductance. Doppler ultrasound demonstrated good agreement and consistency between two days of testing for measuring popliteal blood flow and vascular conductance at rest and exercise.