Portal vein blood flow-effects of pregnancy, gravity, and exercise
Autor: | William Stepanchak, Mary Kortan, Stephanie Faneslow, James F. Clapp, Jodi Tomaselli |
---|---|
Rok vydání: | 2000 |
Předmět: |
Adult
medicine.medical_specialty Posture Hemodynamics Physical exercise Gestational Age Pregnancy Internal medicine medicine.artery medicine Humans Exercise physiology Uterine artery Exercise business.industry Portal Vein Body Weight Obstetrics and Gynecology VO2 max Blood flow medicine.disease Surgery Cardiology Female Splanchnic business Blood Flow Velocity Gravitation |
Zdroj: | American journal of obstetrics and gynecology. 183(1) |
ISSN: | 0002-9378 |
Popis: | Objective: We sought to test the hypotheses that pregnancy increases portal vein blood flow and that regular exercise training during pregnancy limits the flow redistribution away from the splanchnic and uterine circulations in response to either gravitational or exercise-induced hemodynamic stress. Study Design: Portal vein blood flow, which probably reflects changes in uterine blood flow, was estimated with ultrasonography in 6 regularly exercising and 6 physically active control subjects before and during pregnancy after 15 minutes of rest in the left lateral recumbent position, after 5 minutes of standing rest, and immediately and 5 minutes after 20 minutes of treadmill exercise at 55% ± 3% of maximal aerobic capacity. Results: Portal vein blood flow rose significantly during early and mid pregnancy at recumbent rest (from 660 ± 110 to 1090 ± 120 mL/min), standing rest (580 ± 70 to 790 ± 120 mL/min), immediately after exercise (160 ± 30 to 360 ± 60 mL/min), and at 5 minutes of recovery (520 ± 60 to 760 ± 110 mL/min). Before pregnancy, exercise training did not blunt the decremental effects of either gravity or exercise on portal vein blood flow. During mid and late pregnancy, exercise training had no effect on the fall in portal vein blood flow with gravitational stress, but it markedly reduced the decremental effects of exercise (average for the 2 time points, –510 ± 80 vs –840 ± 100 mL/min) and improved recovery at 5 minutes after exercise (940 ± 140 vs 600 ± 130 mL/min). Conclusions: Portal vein blood flow rises significantly during pregnancy, and flow redistribution away from the splanchnic and uterine circulations in response to severe hemodynamic stress is reduced by exercise training in mid and late pregnancy. (Am J Obstet Gynecol 2000;183:167-72.) |
Databáze: | OpenAIRE |
Externí odkaz: |