Doppler flow velocity waveform analysis in high risk pregnancies: a randomized controlled trial. The effect of introduction of umbilical Doppler recordings to obstetric practice. A randomized, controlled trial of computerized physiologic trend monitoring in an intensive care unit. Randomized comparison of routine vs highly selective use of Doppler ultrasound and biophysical scoring to investigate high risk pregnancies. Randomised controlled trial of cardiotocography versus umbilical artery Doppler in the management of small for gestational age fetuses. A randomised controlled trial of admission electronic fetal monitoring in normal labour. Randomised comparison of routine versus highly selective use of Doppler ultrasound in low risk pregnancies. Randomised controlled trial of cardiotocography versus Doppler auscultation of fetal heart at admission in labour in low risk obstetric population. A randomised controlled trial of Doppler ultrasound velocimetry of the umbilical artery in low risk pregnancies. Doppler French Study Group.
To test whether the introduction of Doppler waveform analysis into the ultrasound department of a tertiary level hospital reduces neonatal morbidity and improves obstetric management.
                A randomized controlled trial.
                Department of Ultrasound, King Edward Memorial Hospital, Perth, Western Australia.
                505 women with pregnancy abnormalities referred to an ultrasound department for fetal investigation during the third trimester.
                Continuous wave Doppler studies of umbilical and uteroplacental arterial circulations. Results were revealed to patients and clinicians.
                Principal end point was the duration of neonatal stay in hospital; other end points included the number and type of fetal heart rate monitoring studies, obstetric interventions, frequency of fetal distress, birthweight, Apgar scores and need for neonatal intensive care.
                There was no effect on the duration of neonatal stay in hospital. Small trends in obstetric management were observed with study group patients having fewer contraction stress tests, less likelihood of antepartum fetal distress, and more likelihood of fetal distress after induction of labour leading to emergency caesarean section. Depressed Apgar scores were more frequent in the study group.
                Introduction of Doppler waveform studies did not result in reduced neonatal morbidity but did have a small effect on obstetric management. For each institution the role of Doppler studies in late pregnancy will be influenced by the usage of other tests of fetal welfare already entrenched in clinical practice. To assess the effect on obstetric practice of clinician access to umbilical artery Doppler ultrasound results.
                Randomised controlled trial.
                A large teaching hospital.
                Two thousand two hundred and eighty-nine pregnancies defined as being at risk by referral for Doppler or fetal monitoring.
                Continuous wave Doppler studies of umbilical artery. Results immediately available to clinicians.
                Fetal outcome: perinatal mortality, Apgar score and admission to the neonatal unit. Obstetric intervention: admission to hospital, induction of labour and caesarean section. Use of of fetal well being: cardiotocography, biophysical profile and ultrasound biometry.
                The treatment and control groups were comparable in age, parity, gestation at point of entry and risk features. There were no overall differences in perinatal outcome, obstetric intervention or use of fetal monitoring. Examination of a subset recruited only because of hypertension or suspected intrauterine growth retardation (n = 754) similarly showed no difference attributable to group randomisation. Comparison of only those pregnancies retrospectively defined as low risk and high risk showed more use of cardiotocography in the high risk group with access to Doppler (P = 0.007) but no difference in the low risk group.
                Doppler umbilical artery recording has been shown to perform well in prediction power of antenatal fetal compromise. What has been examined in this study is the response of clinicians to the test. The results suggest that obstetricians do not use the test to modify their risk assessment, and, therefore, the need for fetal monitoring in particular pregnancies. There is a real need for accumulation of information from very large data sets, particularly in the prediction power of Doppler for antenatal fetal compromise from apparently chronic utero-placental cause to guide use of monitoring resources. If simply added to existing fetal monitoring techniques in a hospital where these are widely used, then umbilical artery Doppler recordings may at present simply involve extra resources of staff and expenses, without benefit. To assess whether the provision of computerized physiologic trend data could improve outcome in newborn infants requiring intensive care.
                Randomized, controlled trial, with subsidiary questionnaire studies.
                Tertiary neonatal intensive care unit with 12 intensive care cots.
                All infants admitted between January 1991 and September 1993 who were < or =32 wks gestation or >32 wks gestation, and ventilated for >4 hrs or asphyxiated.
                Randomization to one of four groups for first 7 days of life: A) no display of trend data; B) continuous display of trend data; C1) alternating 24-hr display of trend data, starting with display in first 24 hrs; and C2) alternating 24-hr display of trend data, starting with no display in first 24 hrs.
                The short-term effects of monitoring on patient outcome was judged by volume of colloid given, number of blood gases taken, and by measurement taken from cranial Doppler ultrasound. Medium-term measures included time ventilated, time given supplemental oxygen, death, time to death or discharge, and cranial ultrasound at discharge. Long-term outcome was assessed by neurodevelopmental status at age 1 to 4 yrs of age. Staff and parent questionnaires assessed their respective attitudes to the introduction of this technology. None of the patient outcome measures, short-, medium-, or long-term, demonstrated any significant benefit from the provision of computerized physiologic trend monitoring. Staff questionnaires demonstrated an acceptance of the system and an improved understanding of neonatal physiology as a result of computerized physiologic trends. Parent questionnaires demonstrated increased anxiety caused by the system in 11% of parents, although only 1% of parents continued to have concerns if the system were able to help their child.
                A randomized, controlled trial was unable to demonstrate any benefit to patients resulting from the introduction of a computerized physiologic trend monitoring system. Benefits of the system have been recognized, however, in subsidiary studies, staff education, and research studies. To compare routine versus highly selective use of Doppler ultrasound and biophysical scoring in higher risk pregnancy.
                A pragmatic randomized trial.
                St James's University Hospital, Leeds.
                500 pregnant women at high risk of intrauterine growth retardation or still birth.
                Regular monitoring with biophysical profile assessment and Doppler velocity waveform recording in umbilical and uteroplacental arteries. Results immediately available to clinicians.
                Gestational age at delivery, obstetric intervention rates and short-term neonatal morbidity.
                Risk factors were distributed very evenly between the 250 patients in the study and control groups respectively. A total of 902 biophysical profile and Doppler assessments were done in the 250 study group patients and only in 12 patients in the control group. In the study group, absent end-diastolic flow was found in only 2.7% of all 902 measurements. A persistently abnormal biophysical score was always associated with absence of end-diastolic flow. The mean gestational age at induction of labour was statistically and clinically similar in the two groups and there was no overall statistically significant difference in intervention rates between the two groups. There was a statistically significant lower frequency of depressed 5-min Apgar scores in the study group. Serious neonatal morbidity was also statistically significantly more common in the control group than in the study group.
                The use of Doppler ultrasound in higher risk pregnancies does not lead to an increase in iatrogenic preterm delivery. The total rate of positive tests on Doppler ultrasound is very low and persistently abnormal biophysical scores are unlikely to be found in patients where umbilical end-diastolic blood flow is present. Surrogate measures for fetal damage seem to be improved when clinicians have access to Doppler ultrasound assessments. To compare the impact on use of resources in the management of small for gestational age babies using Doppler ultrasound versus cardiotocography.
                A randomised controlled trial.
                A large district general hospital delivering 5500 to 6000 infants each year, 30% to 35% of which are to women of Pakistani origin.
                One hundred and fifty women delivered of small for gestational age infants.
                Primary outcome measures were length of hospital inpatient stay and induction of labour rates. Secondary outcome measures included caesarean section rates and length of stay on neonatal unit.
                The use of Doppler reduced average hospital inpatient stay from 2.5 days to 1.1 days, compared with cardiotocography (P = 0.036). There was no effect on induction of labour rates or caesarean section rates. There was no significant difference in length of stay on the neonatal unit (P = 0.33). There was a reduction in monitoring frequency and fewer hospital antenatal clinic visits.
                The use of Doppler ultrasound to manage small for gestational age infants reduces the use of resources, compared with cardiotocography. To test the hypothesis that the use of admission Electronic Fetal Monitoring (EFM) for healthy pregnant women in spontaneous labour would result in an increase in continuous EFM when compared to women who have had no admission EFM.
                A randomised controlled trial.
                The Midwives Birth Unit in Glasgow Royal Maternity Hospital, a major urban teaching hospital with approximately 5000 births per year.
                Healthy pregnant women admitted in normal labour, deemed low risk based on the midwives' birth unit admission criteria.
                Women were randomly allocated either to receive a routine 20-minute period of EFM at the time of admission (control group), or to receive no routine admission EFM (study group).
                Primary study outcomes, use of continuous EFM; and use of EFM additional to the admission test. Secondary outcomes: artificial rupture of membranes, use of fetal scalp electrode, fetal blood sample, syntocinon, epidural analgesia, number of vaginal examinations, rate of transfer to labour ward, and reason for transfer.
                There was no statistically significant difference between the groups for use of continuous monitoring, but significantly more women in the control group did receive additional EFM. There was no statistically significant difference between groups for any of the interventions studied.
                The use of admission EFM did not in itself lead to a cascade of intervention. Other factors including setting of care and philosophy of caregivers may have an effect on the rate of intervention in labour. To help answer the question: should Doppler ultrasound of the umbilical circulation be made available to all pregnant women as part of their routine antenatal care?
                A randomised trial.
                St James's University Hospital, Leeds.
                2025 low risk primigravid women.
                Obstetric intervention rates and short term neonatal morbidity.
                The incidence of abnormal Doppler was low (1.7%) with complete absence of end diastolic flow in only 0.3% of cases. No significant differences could be demonstrated between control and study women in any of the outcomes measured.
                This study did not demonstrate any benefit or harm from Doppler ultrasound as a routine screening test for all low risk women, whereas our previous studies have suggested that it is useful in high risk pregnancies. Any marginal returns on extending access to Doppler ultrasound from high risk to all women must be small. Since this test has excellent performance characteristics (sensitivity and specificity) for the prediction of fetal hypoxia and acidosis our results call into question the cost to benefit ratio of all tests designed to predict these outcomes in low risk women. To compare the effect of admission cardiotocography and Doppler auscultation of the fetal heart on neonatal outcome and levels of obstetric intervention in a low risk obstetric population.
                Randomised controlled trial.
                Obstetric unit of teaching hospital
                Pregnant women who had no obstetric complications that warranted continuous monitoring of fetal heart rate in labour.
                Women were randomised to receive either cardiotocography or Doppler auscultation of the fetal heart when they were admitted in spontaneous uncomplicated labour.
                The primary outcome measure was umbilical arterial metabolic acidosis. Secondary outcome measures included other measures of condition at birth and obstetric intervention.
                There were no significant differences in the incidence of metabolic acidosis or any other measure of neonatal outcome among women who remained at low risk when they were admitted in labour. However, compared with women who received Doppler auscultation, women who had admission cardiotocography were significantly more likely to have continuous fetal heart rate monitoring in labour (odds ratio 1.49, 95% confidence interval 1.26 to 1.76), augmentation of labour (1.26, 1.02 to 1.56), epidural analgesia (1.33, 1.10 to 1.61), and operative delivery (1.36, 1.12 to 1.65).
                Compared with Doppler auscultation of the fetal heart, admission cardiotocography does not benefit neonatal outcome in low risk women. Its use results in increased obstetric intervention, including operative delivery. To evaluate the effect on management and outcome of pregnancy of routine umbilical Doppler examination in low risk populations.
                Pragmatic randomised controlled trial.
                Twenty centres caring for low risk pregnant women.
                4187 women were randomly assigned to umbilical Doppler between 28 and 34 weeks of gestation or no routine umbilical Doppler. The women included were at low risk at 28 weeks of gestation defined by a normal ultrasonographic examination at the time of randomisation and no obstetric or medical complications during the first two trimesters of the pregnancy.
                The general characteristics at inclusion were comparable for the two groups. Performance of umbilical Doppler led to a significant increase in the number of ultrasonographic and Doppler examinations subsequently conducted; there were no other effects on the management of the pregnancy. There was no significant difference in fetal distress during labour (odds ratio [OR] 0.96; 95% confidence interval [CI] 0.70-1.33). There were three times fewer perinatal deaths in the Doppler group (three versus nine), but this difference was not significant (OR 0.33; 95% CI 0.06-1.33).
                Based on this trial routine use of umbilical doppler for low risk pregnancy cannot be recommended. More data are needed to reach a definite conclusion of the value of routine Doppler.
There are insufficient data from randomised trials to guide practice regarding the management of DFM. Based on the results of other systematic reviews of management strategies for women whose babies are thought to be at risk of compromise for various reasons, the following strategies show promise and may be prioritised for further research: Doppler ultrasound studies, computerised cardiotocography, and fetal arousal to facilitate cardiotocography.
For settings where electronic fetal assessment methods are not available, clinical fetal arousal tests should be investigated.