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Amnioinfusion: from termination of pregnancy to therapy
Full text linkAMNIOINFUSION: FROM TERMINATION OF PREGNANCY TO THERAPY
Amnioinfusion or infusion of saline into the amniotic cavity was first used as a
technique for late termination of pregnancy in the 1960s (Jonas and Slate. Obstet
Gynecol.1966;27:494-6). By the mid 1970s, transabdominal amnioinfusion of
hypertonic (20%) saline was the most widely used method of pregnancy termination
after 14 weeks in the US. This technique was associated with around 10% morbidity
including hemorrhage requiring transfusion, retained tissue requiring surgical removal,
infection, coagulopathy, and hypernatremia (Ballard and Ballard. Am J Obstet
Gynecol.1972;114:575-81). There were also risks of intravenous, intraperitoneal, or
intramyometrial injection of the saline and thus amnioinfusion for abortion was
abandoned in the 1980s in favour of prostaglandins (PGE2) which were more efficient
and with fewer side effects.
Miyazaki and Taylor were the first to report on the use of saline amnioinfusion
in 42 patients having repetitive variable or prolonged decelerations that did not
respond to conventional therapy, such as maternal position changes and oxygen
administration (Miyazaki and Taylor. Am J Obstet Gynecol.1983;146:670‐8). The
technique used normal saline or ringers lactate infused transcervically through a
catheter into the uterine cavity, or transabdominally using a 'spinal' needle when
membranes are intact. More recently, transcervical amnioinfusion was proposed for
women presenting with thick meconium staining of the amniotic fluid to reduce the risk
of perinatal death and meconium aspiration syndrome. Although the first results
seemed encouraging (Hofmeyr et al.BJOG.1998;105:304-8), the 2006 UK National
Institute for Health and Care Excellence (NICE) concluded that there was insufficient
evidence to support the practice (www.nice.org.uk › guidance › ipg192) and it has
rarely been used for this indication. More recent data from India have suggested that 1
transcervical amnioinfusion in labour for meconium-stained amniotic fluid can be
performed safely in a setup with limited neonatal care facilities, to decrease the
incidence of caesarean deliveries and improve neonatal outcome (Choudhary and
Bano. Arch Gynecol Obstet.2010;282:17-22).
Amnioinfusion was also used prophylactically in various conditions commonly
associated with oligohydramnios to limit the risk of cord compression or
oligohydramnios-related pulmonary hypoplasia (Figure) (Fisk et al.
BJOG.1992;99:464-8) but was not found to improve neonatal outcomes. Two large
trials have assessed whether infusion of fluid into the amniotic cavity could improve
pregnancy outcome after second-trimester premature rupture of the membranes
(AMIPROM trial Roberts et al.UOG 2014;43:490-9;PPROMEXIL-III trial van Teeffelen
et al. BMC Pregnancy Childbirth. 2014; Apr 4;14:128). The first trial suggested an
improvement in long-term healthy survival after amnioinfusion but neither of these
studies showed a significant better outcome after amnioinfusion. In this issue, De
Ruigh et al. (BJOG 2021) report on the long-term outcome of the PPROMEXIL-III trial.
Overall, of the 14 survivors (all born at a median gestational age of 24 weeks), 71%
had no neurodevelopmental delay. The small sample size of this study does not allow
to draw any definitive conclusions and survival without developmental delay nor
respiratory problems did not differ between the treatment arm and controls with no
amnioinfusion. From termination of pregnancy to therapy, amnioinfusion has still to
find its place in modern obstetrics
Assisted reproductive technology and the risk of fetal congenital heart disease: insights from a tertiary-care referral center
Full text linkPurpose: To investigate whether congenital heart diseases exhibit higher rates in pregnancies achieved through assisted reproductive technology (ART) compared to natural conception. Methods: In this retrospective cohort study, multinomial logistic regression was employed to analyze the relationship between categories of congenital heart diseases and three conception groups (IVF, ICSI, and natural pregnancies). The main outcome measures are risks of congenital heart disease categories in IVF and ICSI groups using the natural group as reference. We selected fetuses referred for fetal echocardiography to IRCCS Policlinico Sant’Orsola, Bologna, between January 2005 and November 2023, diagnosed with congenital heart diseases. Results: We categorized the congenital heart diseases into six groups based on anatomical and embryological criteria. The estimated risk of left ventricular outflow tract, valvular, conotruncal, and atrioventricular septal defects was lower in the IVF group compared to natural conception. The estimated risk of valvular and atrioventricular septal defects was lower in the ICSI group vs natural. Conversely, the risk for right heart anomalies was higher both in the IVF and ICSI groups compared to natural conception. Heart rhythm diseases were more frequent in IVF pregnancies. When comparing ART methods, valvular defects, conotruncal defects, and right heart anomalies were more frequently observed in the ICSI group, while atrioventricular septal defects were more common in the IVF group. Conclusion: Significant differences were found in the occurrence of congenital heart diseases in pregnancies conceived through IVF and ICSI, versus those conceived naturally, underscoring the importance of further studying the underlying mechanisms of these associations
Three-dimensional ultrasound in monitoring progression of labor: a reproducibility study
No full textObjective The aim of this study was to evaluate the intraobserver and interobserver reproducibility of measurements, obtained from stored ultrasound volumes, related to fetal head progression in the birth canal. Methods From January to September 2009, serial ultrasound volumes were obtained from women in labor, stored and separately evaluated by two different operators using the SonoVCAD labor software. Volumes were aligned using the pubic bone and the urethra as references. In the sagittal plane of the pelvis, the following data were calculated: head progression distance (the distance between the infrapubic line and the lowest part of the fetal skull), head direction (the angle between the infrapubic line and the major longitudinal axis of the fetal head) and head progression angle (the angle between the longitudinal axis of the pubic bone and a line joining the lowest edge of the pubis to the lowest convexity of the fetal skull). In the transverse plane, the angle formed by the midline with the anteroposterior axis of the maternal pelvis (midline angle) was also measured. For each measurement, intraobserver and interobserver reproducibility was determined. Results We analyzed 30 ultrasound volumes. For all parameters, interobserver variation was significantly higher than intraobserver variation. Reproducibility was good for all parameters, except for the midline angle. Among the different ultrasound measurements, the progression angle presented the highest reproducibility. Conclusions Measurements obtained from stored ultrasound volumes to assess fetal head progression in the second stage of labor have good reproducibility, with progression distance and progression angle being the most reproducible parameters
Intracranial Hemorrhage, Cysts, Tumors, and Destructive Lesions
No full textDestructive cerebral lesions are the result of an insult to a normally developed fetal brain. The most common causes are hemorrhage, hypoxia-ischemia, and infections. However, the pathophysiology is unclear in many cases. The prognosis is usually poor. This chapter describes the main features of fetal intracranial destructive lesions, including intracranial hemorrhages, porencephaly, hydranencephaly, and schizencephaly. Other intracranial lesions that develop late in gestation, including intracranial cysts and intracranial tumors, are also described
Reference charts for umbilical Doppler pulsatility index in fetuses with isolated two-vessel cord
No full textPurpose: To determine reference values for umbilical Doppler pulsatility index in fetuses with isolated two-vessel cord and to compare these values with standard umbilical Doppler pulsatility index curves from 23 to 40 gestational weeks. Methods: A retrospective longitudinal cohort study was conducted between January 2014 and December 2017 in a tertiary referral hospital and included 62 pregnant women with isolated single umbilical artery (two-vessel cord) and 174 measurements. Only uncomplicated term pregnancies were included. A reference curve for umbilical Doppler pulsatility index was built up and compared with a standard curve commonly used for fetuses with three-vessel cord. Results: Umbilical Doppler pulsatility index values were much lower than expected in cases with two-vessel cord compared to 3-vessel cord: mean of the regression equations was 1.02 ± 0.23 vs. 0.86 ± 0.19, respectively (p value < 0.001). This difference was quite constant across the gestational weeks considered, showing that the slopes of the two regressions were very similar. Conclusion: Reference curves for umbilical Doppler pulsatility index in two-vessel cord pregnancies were determined. Pulsatility index values were significantly different compared with those commonly used for three-vessel cord. Using lower reference values for umbilical pulsatility index in cases with two-vessel cord may allow a better identification of fetuses affected with intrauterine growth restriction, thus improving fetal surveillance
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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