Related Experiment Videos
Does the brachial artery Doppler flow velocity waveform reflect changes in downstream impedance?
1Perinatal Unit, Glasgow Royal Maternity Hospital, Scotland.
American Journal of Obstetrics and Gynecology
|December 1, 1991
Summary
Doppler ultrasound reveals significant changes in maternal brachial artery blood flow during pregnancy. These findings in pregnant women indicate altered vascular resistance and cardiac output, reflecting normal physiological adaptations.
Area of Science:
- Obstetrics and Gynecology
- Vascular Physiology
- Diagnostic Ultrasound
Background:
- Pregnancy is associated with significant cardiovascular adaptations.
- Brachial artery Doppler velocimetry is a non-invasive tool to assess vascular function.
Purpose of the Study:
- To investigate brachial artery Doppler flow velocity waveforms in nonpregnant and pregnant women.
- To assess the impact of acute changes in downstream impedance on maternal brachial artery Doppler parameters.
Main Methods:
- Recorded brachial artery Doppler flow velocity waveforms in 10 nonpregnant and 19 pregnant women.
- Applied cold-water immersion to induce acute changes in downstream impedance in 9 pregnant women.
Main Results:
- Pregnant women exhibited higher peak systolic and end-diastolic frequencies and lower pulsatility indices compared to nonpregnant women.
- Cold-water immersion significantly reduced peak systolic and end-diastolic frequencies and increased pulsatility index in pregnant women.
- These Doppler changes normalized within 60 seconds after immersion cessation.
Conclusions:
- Maternal brachial artery Doppler waveforms reflect physiological changes in pregnancy, including altered cardiac output and systemic vascular resistance.
- The brachial artery Doppler waveform is sensitive to acute changes in downstream impedance during pregnancy.
- Doppler velocimetry can assess both chronic adaptations and acute responses in the maternal brachial circulation.