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B Carbonne

Publications and source records attributed to B Carbonne.

At least 19 recordsLinked to original sources
PubMed2001

Tocolysis with nifedipine or beta-adrenergic agonists: a meta-analysis.

OBJECTIVE: To clarify the relative efficacy of nifedipine and beta-agonists for tocolysis. DATA SOURCES: The literature was searched in the following databases: MEDLINE 1965-1998, Embase 1988-1998, Current Contents 1997-1998, and the Cochrane Database for 1998. We also sought unpublished trials and abstracts submitted to major international congresses. Search terms were: "tocolysis," "nifedipine," "calcium channel blocker," "ritodrine," "terbutaline," and "salbutamol." METHODS OF STUDY SELECTION: Randomized controlled trials comparing tocolysis with nifedipine and beta-adrenergic agonists during preterm labor were reviewed. In cases with postrandomization exclusions, authors were contacted to obtain intent-to-treat results and to avoid analytical bias. We identified 11 published and two unpublished randomized trials. TABULATION, INTEGRATION, AND RESULTS: Data were extracted by two reviewers and analyzed by a blinded biostatistician with RevMan 3.1 software from the Cochrane Collaboration. We analyzed nine relevant randomized controlled trials that included 679 patients. Meta-analysis showed that nifedipine was more effective than the beta-agonists in delaying delivery at least 48 hours [odds ratio (OR) 1.52, 95% confidence interval (CI) 1.03, 2.24], or over 34 weeks (OR 1.87, 95% CI 1.11, 3.15). The agents did not differ as to the incidence of deliveries after 37 weeks (OR 1.29, 95% CI 0.85, 1.96) or the neonatal mortality rate (OR 1.51, 95% CI 0.63, 3.65). Treatment with nifedipine was interrupted significantly less often because of side effects (OR 0.12, 95% CI 0.05, 0.29) and led to better neonatal outcomes (fewer infants with respiratory distress syndrome: OR 0.57, 95% CI 0.37, 0.89) or transferred to neonatal intensive care units (OR 0.65, 95% CI 0.43, 0.97). CONCLUSION: With respect to neonatal outcome, nifedipine appears to be more effective than beta-agonists for tocolysis and should be considered for use as a first-line tocolytic agent.

Adrenergic beta-Agonists↗
PubMed2001

[The new tocolytics].

Explore the source record for details and available documents.

Calcium Channel Blockers↗
PubMed2001

[Which tocolytics should be used in 2001?].

Beta-mimetics are the gold standard tocolytic treatment but raise several problems. Despite their recognized efficacy in prolonging pregnancy, the neonatal benefit remains to be proven. There are several contraindications and frequent adverse effects, with a risk of fatal maternal accidents. The lack of reliable criteria for the prediction of preterm birth leads to giving unnecessary treatments to two-thirds of the patients. In this context, obstetrical practices have tended to prefer tocolytics which, with the same efficacy, would have fewer side effects than beta-mimetics and which would not raise a risk of severe complications. Calcium-channel blockers belonging to the dihydropyridin family and ocytocin antagonists would appear to meet the new requirements. In randomized trials versus beta-mimetics, they have been found to have a comparable effect in prolonging pregnancy by 48 hours. Tolerance is better than with beta-mimetics and treatment interruption due to side effects can be avoided. Finally, a meta-analysis of trials comparing calcium inhibitors versus beta-mimetics demonstrated a decrease in respiratory distress syndrome in the neonates and a reduction in the number of transfers to neonatal intensive care. The data accumulated on these new compounds would appear to suggest that they should be used as the first line treatment and not as an alternative to beta-mimetics. Other compounds including NO donors and cyclo-oxygenase 2 inhibitors are under evaluation.

Adrenergic beta-Agonists↗
PubMed2001

[Tocolysis with calcium-channel-blockers].

OBJECTIVE: To evaluate the use of calcium-channel-blockers (CCBs) for tocolysis. METHODS: We reviewed the literature retrieved from the Medline database from 1967 to 200 dealing with fetal toxicity and efficacy of CCBs compared with beta-adrenergic agonists. RESULTS: Data on fetal toxicity in animals were inconsistent. A teratologic effect has been observed during early pregnancy at supratherapeutic dosage. At usual therapeutic dosage, no fetal abnormalities have been observed. The efficacy of CBs for tocolysis is superior to that of beta-adrenergic drugs and allows a reduction of neonatal morbidity. Calcium channel blockers are better tolerated than beta-adrenergic agonists. CONCLUSION: Published data suggest that CCBs could be used a first line tocolytic agents. Although use of CCBs is extremely simple, they should not be prescribed in low-risk outpatients.

Adrenergic beta-Agonists↗
PubMed2000

Place of amniocentesis in the assessment of preterm labour.

OBJECTIVE: To evaluate the benefits and indications for amniocentesis in cases of preterm labor with or without preterm rupture of membranes. METHOD: A review of the literature on amniocentesis in cases of intra-amniotic infection. RESULTS: Amniocentesis is an invasive method that allows the diagnosis of intra-amniotic infection. However, no randomized trials have been performed from which we can assess the benefits and complications of amniocentesis in preterm labor. CONCLUSION: The published data do not justify the routine practice of amniocentesis in preterm labor. More data are needed to evaluate the benefits and complications of this practice. Only randomized trials of patients in preterm labor, comparing those who undergo amniocentesis with those who do not, will clarify the indications for this procedure.

Amniocentesis↗
PubMed2000

A mathematical model of uterine dynamics and its application to human parturition.

We have developed a simple mathematical model with three physiologically significant states to describe the changes in intrauterine pressure associated with a contraction during human parturition. The myometrium is modelled as a set of smooth muscle cells, each of which is in one of three states (quiescent, contracted, refractory) at a given time. These states are occupied according to a cycle governed by three temporal parameters. The solutions of the equations describing the model show an oscillatory behavior for particular values of these parameters, which is very similar to the time dependent development of intrauterine pressure during labor. Due to its non-linear terms, our model could lead to chaotic oscillations (in the mathematical sense), whose clinical counterpart may occur in cases of dystocia. Despite its simplicity, this model appears to be a useful guide to further investigations of the oscillatory behavior of the myometrium, or other smooth muscles, in normal and pathological situations.

Dystocia↗
PubMed2000

Effects of progesterone on prostaglandin E(2)-induced changes in glycosaminoglycan synthesis by human cervical fibroblasts in culture.

Prostaglandins are known to induce cervical ripening and this effect may be mediated by an increase in glycosaminoglycan (GAG) concentration. The aim of this study was to assess the effects of progesterone on prostaglandin E(2) (PGE(2))-induced changes in GAG synthesis by human cervical cells in culture. Human cervical fibroblasts were obtained by cervical biopsies in hormonally active women and cultured. Cells were submitted to an incubation with progesterone or control medium. A second incubation was then performed with increasing concentrations of PGE(2). GAG synthesis by the cervical cells was assayed after extraction, by incorporation of [(3)H]-glucosamine and [(35)S]-sulphate into GAGs. It was found that progesterone alone induced a dose-dependent increase in GAG synthesis. After pre-incubation with progesterone, PGE(2) further increased [(3)H]-glucosamine and [(35)S]-sulphate uptake. However, when expressed as percentage of stimulation, the stimulatory effect of PGE(2) on GAG synthesis was inhibited at high progesterone concentrations. Therefore we concluded that, although high concentrations of progesterone increase the overall synthesis of GAG, they may also play a preventative role against PGE(2)-induced changes in GAG production during pregnancy.

Cells, Cultured↗
PubMed2000

[Use of fetal pulse oximetry during labor].

Fetal surveillance during labor is mainly based on fetal heart rate monitoring in France. In case of abnormal FHR, fetal scalp blood analysis may reduce the rate of cesarean section. Fetal pulse oximetry, a recent second-line technique of fetal monitoring could also reduce obstetrical interventions. Several maternity departments in France and other European countries are currently using this new tool routinely. Several observation studies have shown the potential interest of pulse oximetry. Randomized controlled trials will soon be able to conclude on the real benefits that can be expected from pulse oximetry during therm labor in normally grown fetuses. Other clinical situations such as meconium-stained amniotic fluid, preterm labor or fetal growth retardation remain to be explored.

Female↗
PubMed1999

Detection of hepatitis C virus RNA (HCV RNA) in amniotic fluid: a prospective study.

BACKGROUND/AIMS: Mother-to-infant transmission of hepatitis C virus (HCV) has been reported, but the transmission route is unknown. The aim of our study was to detect HCV RNA in amniotic fluid of pregnant women seropositive for HCV. METHODS: Twenty-two HCV seropositive women were included in the study (median age: 39 years). An amniocentesis was performed in all patients during the 4th month of pregnancy. Sixteen women also tested positive for HCV RNA in serum. The range of HCV RNA titers was 0.3 to 15.1x10(6) Eq/ml (Quantiplex HCV RNA 2.0 Assay, Chiron Diagnostics). Of these 16 viremic patients, four had an anterior placenta, ten had a posterior placenta and the position of the placenta was not determined in two cases. PCR (Amplicor HCV, Roche Diagnostics) was used to detect HCV RNA in the amniotic fluid. We also studied 11 HCV seronegative women as a control group. RESULTS: In the viremic group (n = 16), HCV RNA was detected once in amniotic fluid. The positive specimen was collected from a patient with an HCV RNA serum value equal to 1.1x10(6) Eq/ml. The placenta was in an anterior position. A PCR inhibitor was detected in one case. No HCV RNA was detected in the amniotic fluid of six seropositive non-viremic patients, nor in the control group. Serum HCV RNA was negative in the ten children tested. The woman whose amniotic fluid contained HCV RNA was the mother of one of them. CONCLUSIONS: HCV RNA detection in amniotic fluid is rarely positive. The anterior position of the placenta in the only positive detection cannot rule out contamination of the amniotic fluid during the transplacental amniocentesis.

Adult↗
PubMed1999

Precarity and pregnancy in Paris.

OBJECTIVE: Our purpose was to assess to what extent the absence of health insurance (Social Security) contributes to poor pregnancy outcome. STUDY DESIGN: A prospective, population-based study compared the perinatal outcome of women without Social Security (n=243) to a contemporaneous control group (n=243) and to a group of women (n=32) with Social Security but presenting another risk factor for precarity (a judicial child-mother separation sentence). RESULTS: Prenatal consultations were less frequent and initiated later for women without Social Security than for controls. There was no difference between these two groups concerning maternal morbidity (premature labour, hypertension, gestational diabetes, post-partum complications) or maternal mortality, no difference for the mode of delivery and the rate of low birth-weight, foetal death, and neonatal morbidity (hypoglycaemia, hypocalcemia, anaemia, jaundice, infection and transfer to intensive care unit). The rate of prematurity was not significantly higher in the group without Social Security compared to the control group (11.1% versus 6.2%, P=0.08). However, in the group with Social Security and a court sentence of child mother separation, the rate of fetal growth retardation, prematurity, home delivery, caesarean section, neonatal drug deprivation syndrome and transfer to an intensive care unit was significantly higher compared to the two other groups (P<0.01). CONCLUSION: In our study, absence of Social Security during pregnancy is not a major determinant of poor pregnancy outcome, whereas other factors of precarity seem to be more influential.

Female↗
PubMed1999

[Clinical importance of fetal pulse oximetry. I. Methodological evaluation. Multicenter study. French Study Group on Oximetry of Fetal Pulse].

OBJECTIVE: To evaluate the feasibility of intrapartum fetal pulse oximetry, the distribution of fetal oxygen saturation values, and the relation with the neonatal outcome in a population with an abnormal fetal heart rate (FHR). STUDY DESIGN: A prospective multicenter observational study, from June 1994 to November 1995. Fetal oxygen saturation was continuously recorded using a Nellcor N-400 fetal pulse oximeter in case of abnormal FHR during labor. Simultaneous readings of fetal oxygen saturation and of fetal blood analysis (FBA) were obtained at inclusion and before birth. Feasibility, adverse effects, distribution of fetal oxygen saturation values and relation with neonatal outcome were assessed. RESULTS: 74 patients were included. From 172 attempted sensor placements, the procedure was impossible in three cases and fetal oxygen saturation values were obtained in 164 cases (95.3%). Physicians considered sensor placement an easier task than FBA attempt (easy in 87.5% vs 78.9% for FBA, p = 0.03). The mean reliable signal time (+/- SD) was 64.7 +/- 32% during the first stage. There were no serious adverse effects in the study population. The mean fetal oxygen saturation during the first stage of labor was 42.2 +/- 8.0% (10th-90th centile range: 30-53%). Fetal oxygen saturation was significantly correlated with scalp pH (r = 0.29; p = 0.01) but not with neonatal umbilical artery pH or gas values. There was a significant association between a low fetal oxygen saturation (< 30%) and a poor neonatal condition. CONCLUSION: The feasibility of fetal pulse oximetry is satisfactory in clinical practice. It is easy to use and provides a fair rate of recorded values, even in a population with suspicion of fetal distress. A low fetal oxygen saturation is significantly associated with an abnormal neonatal outcome.

Adult↗