Effect of exercise on portal vein blood flow in man

Purpose: Doppler pulsed flow and electronic scanning allow for instantaneou s measurement of portal vein flow. This method was used to monitor alterati ons in splanchnic blood flow during exercise. Methods: Measurements of port al vein blood flow were performed in eight healthy males at rest and at 10- min intervals during cycle ergometry at 70% of maximal aerobic capacity. Su bjects stopped cycling briefly (similar to 30 s) and stopped breathing whil e measurements were made. Flow was calculated from values obtained for velo city of red blood cell passage and cross-sectional area of the vessel. Resu lts: Cross-sectional area decreased during exercise, resulting in a signifi cant decrease in flow over time (P = 0.0001 by ANOVA). The flow within the portal vein had decreased by 80% after 60 min of exercise (absolute flow, 0 .63 +/- 0.13 L.min(-1) at rest and 0.13 +/- 0.04 L.min(-1) at 60 min). Conc lusion: Electronic Doppler flow measurement of portal vein flow is a viable , noninvasive technique that can be used to measure splanchnic blood flow. Values obtained as a result of intensive exercise are in line with earlier results obtained with other techniques.