A hemodynamic model for pulsatile fluid flow in a pressurized thin-walled elastic tube was applied for the computation of volumetric blood flow and velocity profiles for a given set of system parameters at any selected location along the umbilical artery. The velocity profiles over one heart cycle provide the fetal blood flow velocity waveforms (FVW) from which the usual Doppler indexes (DI) ca...

Background: Abnormal umbilical cord pH can be indicated a distress imposed of newborn and can also be useful in determining the prognosis of the newborn. There are different views about the effect of the neonatal delivery method on the blood gas analysis of the umbilical artery. This study aimed to determine the effect of the method of delivery on umbilical artery pH. Methods: In this Cross ...

VALUE OF DOPPLER ULTRASOUND IN DECISION MAKING FOR CESAREAN SECTION DECISION (Abstract). Based on the Doppler phenomenon, several tools were developed that are able to measure the blood flows in various vessels. The authors aimed at d etermining whether in some cases such an examination is sufficient to decide if a cesarean section is indicated. According to the literature and authors’ own prof...

BACKGROUND The best mode of delivery in cases of intrauterine growth restriction (IUGR) with umbilical artery blood flow changes is not well elucidated. OBJECTIVE To evaluate outcome in IUGR with umbilical artery blood flow changes planned for vaginal delivery after a negative oxytocin challenge test (OCT). METHODS In 84 term singleton pregnancies with suspected IUGR and no unanimous indica...

The flow velocity wave forms generated by Doppler ultrasound examination of the umbilical artery were correlated with fetoplacental blood flow and numerically expressed as a ratio between the systolic (A) and the end-diastolic point (B). The technique is non-invasive and simple to perform. A cohort analytical study was done to see whether useful information could be obtained from the A/B ratio ...

We have performed serial haemodynamic investigations in 20 women undergoing elective Caesarean section under continuous spinal anaesthesia with a 32-gauge catheter with 0.5% heavy bupivacaine. Cardiac output was measured by Doppler and cross-sectional echocardiography at the aortic valve. Doppler flow velocity waveforms were recorded also from the umbilical artery. A block to T4 or above was ac...

Umbilical artery\vein, middle cerebral artery, and ductus venosus Doppler velocimetry were performed at 33 weeks of gestation in the settings of an intrauterine growth restricted fetus during a heart rate deceleration. Interestingly, we recorded a sudden onset redistribution of fetal blood flow with fetal bradycardia. Spontaneous normalization of waveforms was observed once fetal heart rate ret...

The information provided by Doppler ultrasound examination during labor permits the understanding of the mechanisms regarding the physiology and pathophysiology of feto-placental exchange and the fetal adaptive systems. There are certain technical difficulties related to intrapartum Doppler ultrasound examination. The investigated sites are the uterine arteries, umbilical arteries, fetal circul...

The fetal internal carotid artery and umbilical artery flow velocity time waveforms were studied in 17 consecutive twin pregnancies. The pulsatility index was calculated for each fetus in each artery as an index of vascular resistance. All studies were done within 14 days before delivery. In 8 pregnancies both fetuses were of birthweight appropriate for gestational age; whereas, in 9 patients o...