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Zarko Alfirevic

Publications and source records attributed to Zarko Alfirevic.

At least 19 recordsLinked to original sources
PubMed2006

Issues of informed consent for intrapartum trials: a suggested consent pathway from the experience of the Release trial [ISRCTN13204258].

Service users within the NHS are increasingly being asked to participate in clinical research. In Liverpool Women's NHS Foundation Trust, approximately 35% of women take part in research during their pregnancy. For many studies the consent process is simple; information is provided and signed consent is given. There is a difficulty, however, with obtaining informed consent from women in pregnancy who become eligible only when they develop unforeseen complications, especially when they occur acutely. The problem is compounded with women in labour who may be frightened, vulnerable, in pain, under the effect of opiate analgesia, or all of the above. If research to improve the care of these women is to continue, then special consent procedures are needed. These procedures must ensure that the woman's autonomy is protected whilst recognising that women under these circumstances vary enormously, both in their desire for information and their ability to comprehend it. This paper will discuss the obtaining of consent in this situation, and describe an information and consent pathway for intrapartum research which has been developed in collaboration with consumer groups as a way in which these issues can be tackled.

Editorial↗
PubMed2006

Intrapartum fetal emergencies.

Labour is one of the shortest yet most hazardous journeys humans take during their lifetime. Currently, our methods of identifying those fetuses at particular risk of compromise during labour are limited. Antepartum tests of placental reserve give little information about an individual fetus's ability to cope with passage through the birth canal and some might already have received a silent insult earlier in the pregnancy that places them at increased risk. In addition to the normal processes of labour, other, more unpredictable factors can act to place the fetus in acute danger.

Birth Injuries↗
PubMed2006

Oral misoprostol administration for labor induction.

Using oral agents for induction of labor would reduce the need for repeated vaginal examinations; this is more acceptable to women and could reduce infection rates. A systematic review was conducted of 41 randomized trials comparing oral misoprostol to other induction agents. Oral misoprostol is effective at achieving vaginal delivery, and may have benefits over both vaginal and intracervical dinoprostone. Although it does not achieve vaginal delivery as quickly as vaginal misoprostol, the rates of hyperstimulation are lower when using comparable doses. As the primary consideration should be safety rather than speed, an oral regimen using a maximum of 50 mcg 4 hourly is recommended.

Administration, Oral↗
PubMed2006

Effect of different partogram action lines on birth outcomes: a randomized controlled trial.

OBJECTIVE: The World Health Organization recommends partograms with a 4-hour action line, denoting the timing of intervention for prolonged labor; others recommend earlier intervention. We assessed the effect of different action line positioning on birth outcomes. METHODS: A randomized trial of primigravid women with uncomplicated pregnancies, in spontaneous labor at term, was conducted in the northwest of England. Women were assigned to have their labors recorded on a partogram with an action line 2 or 4 hours to the right of the alert line. If progress crossed the action line, diagnosis of prolonged labor was made and managed according to standard protocol. Primary outcomes were rate of cesarean delivery and maternal satisfaction. RESULTS: A total of 3,000 women were randomly assigned to groups; 2,975 (99.2%) were available for analysis. Questionnaires were completed by 1,929 (65%) women. There were no differences in cesarean delivery rate (136/1,490 compared with 135/1,485; relative risk [RR] 1, 95% confidence interval [CI] 0.80-1.26) or women dissatisfied with labor experience (72/962 compared with 81/967; RR 0.89, 95% CI 0.66-1.21). More women assigned to the 2-hour arm had labors that crossed the action line (854/1,490 compared with 673/1,485; RR 1.27, 95% CI 1.18-1.37); received more intervention (772/1,490 compared with 624/1,485; RR 1.23, 95% CI 1.14-1.33); and, if admitted to the midwife-led unit, were transferred for consultant-led care (366/674 compared with 285/666; RR 1.26, 95% CI 1.13-1.42). CONCLUSION: In this birth setting, for primigravid women selecting low intervention care, the 2-hour partogram increases the need for intervention without improving maternal or neonatal outcomes, compared with the 4-hour partogram, advocated by the World Health Organization. CLINICAL TRIAL REGISTRATION: Current Controlled Trials, http://www.controlled-trials.com/isrctn/trial/|/0/78346801.html, ISRCTN78346801.

Adult↗
PubMed2006

Controlled-release misoprostol vaginal insert in parous women for labor induction: a randomized controlled trial.

OBJECTIVE: To assess the ability of a controlled-release misoprostol vaginal insert to induce labor using dose reservoirs of 25, 50, 100, and 200 microg. METHODS: This double-blind, dose ranging, randomized study was carried out in parous women requiring induction of labor at term. Each woman was randomly assigned to receive a single misoprostol vaginal insert that could remain in place for up to 24 hours and was removed for onset of active labor, an adverse event, or having reached 24 hours in situ. The primary outcome measure was time from insertion of the misoprostol vaginal insert to vaginal delivery of the neonate. RESULTS: A total of 124 women participated in the study. The median time to vaginal delivery was 27.5, 19.1, 13.1, and 10.6 hours for the 25-, 50-, 100-, and 200-microg doses, respectively. The percentage of women who delivered vaginally within 12 hours was 9%, 14%, 47%, and 53% (P<.001 using the 25-microg group as the comparator) and within 24 hours was 42%, 79%, 81%, and 70% (P=.003). Uterine hyperstimulation syndrome occurred in one woman who received the 25-mug, two women who received the 100-microg, and three women who received the 200-microg dose reservoirs. CONCLUSION: Misoprostol vaginal inserts effectively induced labor in pregnant parous women at term. LEVEL OF EVIDENCE: I.

Administration, Intravaginal↗
PubMed2006

Induction of labour with previous caesarean delivery: where do we stand?

PURPOSE OF REVIEW: This paper reviews the literature to elucidate the international stance on induction of labour in women with previous caesarean section. RECENT FINDINGS: There is no evidence to suggest that current induction methods are less effective in women with previous caesarean section. It would, therefore, seem logical to use the same regimens as for women with intact uteri, including prostaglandins, particularly in women with unfavourable cervices. The clinical decision making and counselling, however, will always focus on safety, not effectiveness. There is no question that induction of labour is associated with higher risk of uterine rupture, but quantifying this risk remains elusive. SUMMARY: For the present, we will continue our practice, based on the sources of the best evidence available. Improvements in obstetric care have not only reduced the risks associated with uterine rupture but also risks associated with caesarean section. Therefore, both elective caesarean section and induction of labour, with or without prostaglandins, are reasonable choices for women who need induction with previous caesarean section. The efforts to better quantify the benefits/risks of various policies and regimens should continue, but should be complemented with qualitative studies to obtain crucial insight into the demands and challenges confronting women and clinicians to identify factors influencing their decision-making or their preferences.

Cesarean Section↗
PubMed2006

How to repair an anal sphincter injury after vaginal delivery: results of a randomised controlled trial.

OBJECTIVE: To compare two surgical techniques and two types of suture material for anal sphincter repair after childbirth-related injury. DESIGN: Factorial randomised controlled trial. SETTING: Tertiary referral maternity unit. POPULATION: Women with an anal sphincter injury sustained during childbirth. METHOD: Women were randomised into four groups: overlap repair with polyglactin (Vicryl); end-to-end repair with polyglactin (Vicryl); overlap repair with polydioxanone (PDS); and end-to-end repair with PDS. All repairs were completed as a primary procedure by staff trained in both methods. MAIN OUTCOME MEASURES: Suture-related morbidity at six weeks. Bowel symptoms at 3, 6 and 12 months. Anorectal physiology at three months. Quality of life scores at 3 and 12 months. RESULTS: One hundred and fifty women (1.5% of deliveries) were eligible and 112 (75%) were randomised. One hundred and three (92%) attended follow up visit at 6 weeks, 89 (80%) at 3 months, 79 (71%) at 6 months and 60 (54%) at 12 months. At six weeks, there was no difference in suture-related morbidity between groups (P=0.11) and 70% patients were completely asymptomatic. Incidence of bowel symptoms and quality of life disturbances were low, with no differences between the four groups. CONCLUSION: Obstetric anal sphincter repair carried out by appropriately trained staff is associated with low morbidity, irrespective of the suture material and repair method used.

Adult↗
PubMed2005

Individual patient data meta-analysis : Cervical stitch (cerclage) for preventing pregnancy loss in women.

BACKGROUND: Cervical cerclage is a surgical procedure involving suturing the cervix with a purse type stitch to keep it closed during pregnancy. This procedure has been used widely in the management of pregnancies considered at high risk of preterm delivery. Several observational studies into the efficacy of cervical cerclage have claimed high rates of successful pregnancy outcome in women with a poor obstetric history attributed to cervical incompetence. However, a recent aggregate data Cochrane review found no such conclusive evidence from seven included randomised studies. Current data suggests that cervical cerclage is likely to benefit women considered to be 'at very high risk' of a second trimester miscarriage due to a cervical factor, however identifying such women remains elusive and many women may be treated unnecessarily. Undertaking an individual patient data (IPD) meta-analysis of the studies will allow us to investigate whether treatment is more effective in particular subgroups. Such an analysis will also provide a more powerful analysis of the predictors of preterm delivery and pregnancy loss, including ultrasound measurement of cervical length, and will allow a more complete analysis of 'time to event' outcomes. METHODS/DESIGN: The analysis will include data from randomised trials comparing the intervention of elective cerclage versus no cerclage or bedrest to prevent miscarriage or pre-term labour. A specific list of data will be requested for each trial, including demographic and obstetric history data. The primary outcomes of interest will be neonatal mortality/morbidity. Attention will also be given to secondary outcomes such as time from randomisation to delivery, preterm delivery before 32 weeks and maternal morbidity. An intention to treat analysis will be performed, with attention paid to assessing clinical and statistical heterogeneity. Multilevel models with patients and trials as the two levels will be explored to investigate treatment effect on various outcomes. Patient-level covariates will be incorporated into the models in an attempt to account for statistical heterogeneity as well as to investigate interactions with treatment effect. DISCUSSION: Predictive models generated from our analysis should lead to more effective counselling of women at risk and a more cost effective use of cerclage.

Journal Article↗
PubMed2005

The evidence base for fetal medicine.

This chapter looks at the evidence base for the practice of fetal medicine and surgery. There is very little good-quality research and much activity is based on case reports and series. However, the philosophy of evidence-based practice is now accepted and new randomized trials are being published in the literature (e.g. fetal endoscopic tracheal occlusion for congenital diaphragmatic hernia and laser treatment of the twin-to-twin transfusion syndrome). Many well established techniques would not be suitable for randomized trials but, as new techniques related to established practice are introduced (e.g. middle cerebral artery Doppler assessment), well-designed trials are essential to ensure they are safe, clinically useful and at least as good as standard practice. In this unique area of medicine, where ethical and emotional issues interplay with clinical practice, it is important not to introduce exciting techniques without solid evidence that they are beneficial both in the short and the long term.

Chromosome Aberrations↗
PubMed2005

Uterine rupture after induction of labour in women with previous caesarean section.

BACKGROUND: The issues related to safety of induction of labour in women with previous caesarean section remain controversial. The main adverse outcome fuelling this debate is a "small" risk of uterine rupture that is potentially devastating for both the mother and the fetus. OBJECTIVE: To estimate the risk of uterine rupture or dehiscence in women who require induction of labour with previous caesarean sections. DESIGN: Five year retrospective review of computerised hospital records and case note review of index cases. SETTING: Large inner city teaching hospital. POPULATION: Two hundred and five women who had their labour induced with history of one lower segment caesarean section. METHODS: This study was conducted at Liverpool Women's Hospital, a tertiary referral centre, with approximately 6000 births per annum. We searched the hospital's computerised records of deliveries from June 1997 to June 2002 and reviewed all indications and outcomes of induction of labour in women with one previous caesarean section. Women with singleton pregnancy and cephalic presentation were then divided into three groups: those with one previous caesarean section and no previous vaginal deliveries, those whose last delivery was a caesarean section but had delivered vaginally before and those whose last delivery was by vaginal route, but had had one caesarean section in the past. MAIN OUTCOME MEASURES: Uterine rupture or dehiscence, adverse neonatal outcome. RESULTS: Two hundred and five women were included. There were four cases of uterine rupture and one dehiscence (2.4%, 95% CI 0.8-5.6%). Two babies were profoundly acidotic at birth, but all five neonates were healthy when discharged from hospital with no long term morbidity. All five cases occurred in the group of women with no previous vaginal deliveries. The intrauterine pressure catheter recordings had contributed to the diagnosis of uterine rupture/dehiscence in three out of five cases. CONCLUSION: In women with previous caesarean section and no vaginal deliveries, induction of labour carries a relatively high risk of uterine rupture/dehiscence despite all precautions, including intrauterine pressure monitoring.

Cohort Studies↗
PubMed2005

Risk scoring system for prediction of obstetric anal sphincter injury.

OBJECTIVE: The objective was to begin the process of developing an antenatal risk scoring system, as a first step towards examining whether elective Caesarean section for women at high risk of injury could be an effective and acceptable intervention. DESIGN: Retrospective study. SETTING: Tertiary maternity unit in the UK. POPULATION: One hundred and twenty-three women who sustained an obstetric anal sphincter injury (OASI) and 123 controls without OASI. METHODS: Case notes of women with a third or fourth degree tear between 1997 and 1999 were examined for risk factors. Controls matched for age and week of delivery were identified from the maternity record database and case records reviewed for the presence of risk factors. Unweighted and weighted risk scores were produced using odds ratios, and compared between cases and controls. Receiver operating characteristics (ROC) curve analysis of the risk scores was performed to discriminate between cases and controls and to calculate the sensitivity and specificity of each scoring system. MAIN OUTCOME MEASURES: Odds ratio (OR) and 95% confidence interval (CI) for each risk factor. Sensitivity and specificity from ROC curves for weighted and unweighted risk score. RESULTS: Among the cases there were more nulliparous women (OR 1.77; CI 1.05-2.99) and a trend towards more women with an episiotomy (OR 1.57; CI 0.99-2.47). Among women with sphincter injury, trends towards more epidurals (OR 1.64; CI 0.97-2.75), and more babies weighing more than 4000 g among (OR 1.45; CI 0.85-2.49) were noted. The median unweighted risk score was 2 for cases and 2 for controls (P= 0.05), while the weighted risk score was 2.1 and 1.37 (P= 0.03), respectively. The ROC curves approximated to a straight line demonstrating very poor discrimination between cases and controls. CONCLUSION: The predictive test performed poorly, suggesting that the risk factors identified do not exert a large enough effect in a cohort of this size.

Adult↗
PubMed2005

The Release Trial: a randomised controlled trial of umbilical vein oxytocin versus placebo for the treatment of retained placenta.

HYPOTHESIS: Intraumbilical injection of oxytocin reduces the incidence of manual removal compared with placebo in the treatment of retained placenta. ENTRY CRITERIA: The women recruited will be stable haemodynamically, not bleeding vaginally, over 34 weeks of gestation and with a retained placenta for at least 30 minutes. TREATMENT ARMS: Oxytocin (50 IU) or sterile water (in identical vials) in 25 mL saline injected through an intraumbilical venous catheter. SAMPLE SIZE: Five hundred seventy-two women. PRIMARY ENDPOINT: Need for manual removal of placenta. CENTRES: Initially, there will be two study sites in the UK (Liverpool and Sheffield) and five in Uganda (Mulago, Nsambia, Mengo, Rubaga and Arua). FUNDING: World Health Organization and WellBeing of Women.

Adult↗
PubMed2005

Progress of first stage of labour for multiparous women: an observational study.

As there is no universal definition of 'normal' labour, diagnosing prolonged labour is inherently difficult. Simple charts (partograms) are used to aid this process; however, there are little empirical data on which to base such charts. Therefore, we monitored 403 multiparous women, in the first stage of labour with uncomplicated term pregnancies, in a midwife-led unit. They had vaginal examinations every 2 hours, and we modelled rates of cervical dilatation for all women, either to the end of the first stage of labour or to the point of transfer for intervention. Overall, the median rate of dilatation was 1.9 cm/hour and the 5th percentile was 0.5 cm/hour. There was a weak positive correlation between initial dilatation and rate of dilatation (r= 0.2). Individualised computer-based partograms incorporating some of the factors that affect progress might prove useful in the future.

Adult↗