Blood flow and behavioural states in the human fetus

The objective of the present study was five-fold: The first objective was to establish in normal pregnancy a possible relationship between the flow velocity waveform in the fetal descending aorta and fetal behavioural state, in particular states 1F and 2F according to the classification of Nijhuis et al (1982). These two behavioural states were studied because of the high incidence of 1F (32%) and 2F (42%) at 38 weeks and the marked differences in fetal heart rate pattern, fetal eye movements and fetal body movements between these two behavioural states (Nijhuis et al, 1982). State 3F and 4F were excluded from the study because of the low incidence of these behavioural states, respectively 1% and 7% of the recording time (Nijhuis et a!, 1982). Moreover during behavioural state 4F the fetus moves continuously too vigorous to obtain reliable blood flow velocity waveforms. Blood flow velocity waveforms were recorded at 37-38 weeks of gestation, since only then welldefined behavioural states could be expected (Chapter 3.1). The characteristic blood flow velocity changes in the fetal descending aorta observed during intrauterine growth retardation (IUGR) prompted a similar behavioural state related study in this high risk group and represented our second objective, the results of which can be found in Chapter 3.2. Doppler flow measurements are increasingly performed during the early third trimester of pregnancy for the early detection and evaluation of intrauterine growth retardation. The results obtained at 37-38 weeks justified a repeat of this study during the early third trimester of pregnancy. At 27-28 weeks of gestation there already is a clear periodicity of state variables, but there is no proper synchronization in their cyclic appearance, thus allowing elucidation of the role of separate variables on possible flow velocity waveform changes in the fetal descending aorta. This was the third objective of our study; the data are presented in Chapter 3.3. Following the introduction of an ultrasound method for recording blood flow velocity waveforms in the fetal internal carotid artery (Wladimiroff et al, 1986), the fourth objective was to relate these waveforms to fetal behavioural states in normal pregnancy at 37-38 weeks of gestation. It was decided to also include the umbilical artery in the study, since flow velocity waveforms from this vessel are often documented with respect to the early detection of IUGR. From the results collected in this cross-sectional study on blood flow velocity waveforms in the internal carotid artery as well as the earlier observation that during the last four weeks of gestation the pulsatility index in this vessel displays a gradual decline (Wladimiroff et al, 1987b), it was decided to also perform the behavioural ·state related study in the fetal internal carotid artery in a longitudinal design between 36 and 41 weeks of gestation. This would provide an answer to the question as to the role of fetal behavioural states in the fore-mentioned reduction in PI during late pregnancy. The results from the cross-s~ctional study are presented in Chapter 4.1, the results from the longitudinal study can be found in Chapter 4.2. The fifth objective of our study was to elucidate the possible role of fetal behavioural states in fetal internal carotid artery and umbilical artery blood flow measurements during IUGR. We, therefore, first established the incidence and magnitude of flow velocity waveform changes in these two vessels in the presence of IUGR with particular emphasis on the PI umbilical artery /internal carotid artery ratio as a possible predictor of fetal growth retardation. Results are presented in Chapter 4.3. This was followed by a cross-sectional study at 37-38 weeks of gestation, during which blood flow velocity waveforms in both vessels in IUGR were documented during behavioural state 1F and 2F. The data from this part of the investigation can be found in Chapter 4.4

IMproving PArticipation of patients in Clinical Trials - rationale and design of IMPACT

BACKGROUND: One of the most commonly reported problems of randomised trials is that recruitment is usually slower than expected. Trials will cost more and take longer, thus delaying the use of the results in clinical practice, and incomplete samples imply decreased statistical power and usefulness of its results. We aim to identify barriers and facilitators for successful patient recruitment at the level of the patient, the doctor and the hospital organization as well as the organization and design of trials over a broad range of studies. METHODS/DESIGN: We will perform two cohort studies and a case-control study in the Netherlands. The first cohort study will report on a series of multicenter trials performed in a nationwide network of clinical trials in obstetrics and gynaecology. A questionnaire will be sent to all clinicians recruiting for these trials to identify determinants - aggregated at centre level - for the recruitment rate. In a case control-study nested in this cohort we will interview patients who refused or consented participation to identify factors associated with patients' consent or refusal. In a second cohort study, we will study trials that were prospectively registered in the Netherlands Trial Register. Using a questionnaire survey we will assess whether issues on hospital organization, trial organization, planning and trial design were associated with successful recruitment, i.e. 80% of the predefined number of patients recruited within the planned time. DISCUSSION: This study will provide insight in barriers and facilitators for successful patient recruitment in trials. The results will be used to provide recommendations and a checklist for individual trialists to identify potential pitfalls for recruitment and judge the feasibility prior to the start of the study. Identified barriers and motivators coupled to evidence-based interventions can improve recruitment of patients in clinical trials

Роль страдающей депрессией матери в развитии личности ребенка

С позиций психодинамического подхода показана роль страдающей депрессией матери в формировании личности ребенка на первых этапах его постнатального развития и ее влияние на его психическое здоровье в дальнейшем.The role of the mother with depression in development of the child's personality at the first stages of the postnatal period as well as its influence on his/her mental state in future are shown from the perspective of a psychodynamic approach

Resonant two-site tunnelling dynamics of bosons in a tilted optical superlattice

We study the non-equilibrium dynamics of a 1D Bose-Hubbard model in a gradient potential and a superlattice, beginning from a deep Mott insulator regime with an average filling of one particle per site. Studying a quench that is near resonance to tunnelling of the particles over two lattice sites, we show how a spin model emerges consisting of two coupled Ising chains that are coupled by interaction terms in a staggered geometry. We compare and contrast the behavior in this case with that in a previously studied case where the resonant tunnelling was over a single site. Using optimized tensor network techniques to calculate finite temperature behavior of the model, as well as finite size scaling for the ground state, we conclude that the universality class of the phase transition for the coupled chains is that of a tricritical Ising point. We also investigate the out-of-equilibrium dynamics after the quench in the vicinity of the resonance and compare dynamics with recent experiments realized without the superlattice geometry. This model is directly realizable in current experiments, and reflects a new general way to realize spin models with ultracold atoms in optical lattices.Comment: 12 pages, 6 figure

Pessaries in multiple pregnancy as a prevention of preterm birth: the ProTwin Trial

Contains fulltext : 79491.pdf (publisher's version ) (Open Access)BACKGROUND: Multiple pregnancies are at high risk for preterm birth, and therefore an important cause of infant mortality and morbidity. A pessary is a simple and potentially effective measure for the prevention of preterm birth. Small studies have indicated its effectiveness, but large studies with sufficient power on the subject are lacking. Despite this lack of evidence, the treatment is at present applied by some gynaecologists in The Netherlands. METHODS/DESIGN: We aim to investigate the hypothesis that prophylactic use of a cervical pessary will be effective in the prevention of preterm delivery and the neonatal mortality and morbidity resulting from preterm delivery in multiple pregnancy. We will evaluate the costs and effects of this intervention. At study entry, cervical length will be measured. Eligible women will be randomly allocated to receive either a cervical pessary or no intervention. The cervical pessary will be placed in situ at 16 to 20 weeks, and will stay in situ up to 36 weeks gestation or until delivery, whatever comes first.The primary outcome is composite bad neonatal condition (perinatal death or severe morbidity). Secondary outcome measures are time to delivery, preterm birth rate before 32 and 37 weeks, days of admission in neonatal intensive care unit, maternal morbidity, maternal admission days for preterm labour and costs. We need to include 660 women to indicate a reduction in bad neonatal outcome from 7.2% without to 3.9% with a cervical pessary, using a two-sided test with an alpha of 0.05 and a power of 0.80. DISCUSSION: This trial will provide evidence on whether a cervical pessary will decrease the incidence of early preterm birth and its concomitant bad neonatal outcome in multiple pregnancies. TRIAL REGISTRATION: Current Controlled Trials: NTR 1858

Assessment of perinatal outcome after sustained tocolysis in early labour (APOSTEL-II trial)

Contains fulltext : 80242.pdf (publisher's version ) (Open Access)BACKGROUND: Preterm labour is the main cause of perinatal morbidity and mortality in the Western world. At present, there is evidence that tocolysis for 48 hours is useful in women with threatened preterm labour at least before 32 weeks. This allows transfer of the patient to a perinatal centre, and maximizes the effect of corticosteroids for improved neonatal survival. It is questionable whether treatment with tocolytics should be maintained after 48 hours. METHODS/DESIGN: The APOSTEL II trial is a multicentre placebo-controlled study. Pregnant women admitted for threatened preterm labour who have been treated with 48 hours corticosteroids and tocolysis will be eligible to participate in the trial between 26+0 and 32+2 weeks gestational age. They will be randomly allocated to nifedipine (intervention) or placebo (control) for twelve days or until delivery, whatever comes first.Primary outcome is a composite of perinatal death, and severe neonatal morbidity up to evaluation at 6 months after birth. Secondary outcomes are gestational age at delivery, number of days in neonatal intensive care and total days of the first 6 months out of hospital. In addition a cost-effectiveness analysis will be performed. Analysis will be by intention to treat. The power calculation is based on an expected 11% difference in adverse neonatal outcome. This implies that 406 women have to be randomised (two sided test, beta 0.2 at alpha 0.05). DISCUSSION: This trial will provide evidence as to whether maintenance tocolysis reduces severe perinatal morbidity and mortality in women with threatened preterm labour before 32 weeks. TRIAL REGISTRATION: Clinical trial registration: http://www.trialregister.nl, NTR 1336, date of registration: June 3rd 2008

Cost-effectiveness of recurrence risk guided care versus care as usual in women who suffered from early-onset preeclampsia including HELLP syndrome in their previous pregnancy (the PreCare study)

Contains fulltext : 87321.pdf (publisher's version ) (Open Access

Cost-effectiveness of fibronectin testing in a triage in women with threatened preterm labor: alleviation of pregnancy outcome by suspending tocolysis in early labor (APOSTEL-I trial)

BACKGROUND: At present, women with threatened preterm labor before 32 weeks of gestation are, after transfer to a perinatal center, treated with tocolytics and corticosteroids. Many of these women are treated unnecessarily. Fibronectin is an accurate predictor for the occurrence of preterm birth among women with threatened preterm labor. We will assess whether triage of these women with fibronectin testing, cervical length or their combination is cost-effective. METHODS/DESIGN: We will investigate a prospective cohort of women referred to a perinatal centre for spontaneous threatened preterm labor between 24 and 34 weeks with intact membranes. All women will be tested for fibronectin and cervical length. Women with a cervical length <10 mm and women with a cervical length between 10-30 mm in combination with a positive fibronectin test will be treated with tocolytics according to local protocol. Women with a cervical length between 10-30 mm in combination with a negative fibronectin test will be randomised between treatment with nifedipine (intervention) and placebo (control) for 48 hours. Women with a cervical length > 30 mm will be managed according to local protocol. Corticosteroids may be given to all women at the discretion of the attending physician. Primary outcome measure will be delivery within 7 days. Secondary outcome measures will be neonatal morbidity and mortality, complications of tocolytics, costs and health related quality of life. The analysis will be according to the intention to treat principle. We anticipate the probability on preterm birth within 7 days in the group of women with a negative fibronectine test to be 5%. Two groups of 110 women will be needed to assure that in case of non-inferiority the difference in the proportion of preterm deliveries < 7 days will be within a prespecified boundary of 7.5% (one sided test, beta 0.2, alpha 0.05). Data obtained from women with a positive and negative fibronectin tests in both the cohort study and the trial will be integrated in a cost-effectiveness analysis that will assess economic consequences of the use of fibronectin. DISCUSSION: This study will provide evidence for the use of fibronectin testing as safe and cost-effective method in a triage for threatened preterm labor. TRIAL REGISTRATION: Nederlands Trial Register (NTR) number 1857, http://www.trialregister.nl

How to monitor pregnancies complicated by fetal growth restriction and delivery below 32 weeks: a post-hoc sensitivity analysis of the TRUFFLE-study.

OBJECTIVES: In the recent TRUFFLE study it appeared that, in pregnancies complicated by fetal growth restriction (FGR) between 26 and 32 weeks, monitoring of the ductus venosus (DV) combined with computerised cardiotocography (cCTG) as a trigger for delivery, increased the chance of infant survival without neurological impairment. However, concerns in interpretation were raised as DV monitoring appeared associated with a non-significant increase in fetal death, and part of the infants were delivered after 32 weeks, after which the study protocol was no longer applied. This secondary sensitivity analysis focuses on women who delivered before 32 completed weeks, and analyses fetal death cases in detail. METHODS: We analysed the monitoring data of 317 women who delivered before 32 weeks, excluding women with absent infant outcome data or inevitable perinatal death. The association of the last monitoring data before delivery and infant outcome was assessed by multivariable analysis. RESULTS: The primary outcome (two year survival without neurological impairment) occurred more often in the two DV groups (both 83%) than in the CTG-STV group (77%), however the difference was not statistically significant (p = 0.21). Nevertheless, in surviving infants 93% was free of neurological impairment in the DV groups versus 85% in the CTG-STV group (p = 0.049). All fetal deaths (n = 7) occurred in women allocated to DV monitoring, which explains this difference. Assessment of the monitoring parameters that were obtained shortly before fetal death in these 7 cases showed an abnormal CTG in only one. Multivariable regression analysis of factors at study entry demonstrated that higher gestational age, larger estimated fetal weight 50th percentile ratio and lower U/C ratio were significantly associated with the (normal) primary outcome. Allocation to the DV groups had a smaller effect, but remained in the model (p < 0.1). Assessment of the last monitoring data before delivery showed that in the CTG-STV group abnormal fetal arterial Doppler was significantly associated with adverse outcome. In contrast, in the DV groups an abnormal DV was the only fetal monitoring parameter that was associated with adverse infant outcome, while fetal arterial Doppler, STV below CTG-group cut-off or recurrent fetal heart rate decelerations were not. CONCLUSIONS: In accordance with the results of the overall TRUFFLE study of the monitoring-intervention management of very early severe FGR we found that the difference in the proportion of infants surviving without neuroimpairment (the primary endpoint) was non-significant when comparing timing of delivery with or without changes in the DV waveform. However, the uneven distribution of fetal deaths towards the DV groups was likely by chance, and among surviving children neurological outcomes were better. Before 32 weeks, delaying delivery until abnormalities in DVPI or STV and/or recurrent decelerations occur, as defined by the study protocol, is therefore probably safe and possibly benefits long-term outcome