João Renato Bennini

Fetoscopic Endotracheal Occlusion for Severe Isolated Diaphragmatic Hernia: Initial Experience from a Single Clinic in Brazil

Objective: To report on the initial experience in a single Brazilian university clinic of the use of fetoscopic endotracheal occlusion (FETO) to treat severe isolated congenital diaphragmatic hernia (CDH). Methods: The inclusion criteria for FETO for this prospective study were isolated CDH and intrathoracic herniation of the liver, as well as the lung area to head circumference ratio (LHR) <1.0. The main variables evaluated were LHR and observed to expected (o/e) LHR before and after FETO, gestational age (GA) at FETO, reversal of tracheal occlusion (TO), and birth and discharge of a living child from the hospital. Results: Among 8 isolated left-sided CDH cases with normal karyotypes, the median LHR and o/e LHR before FETO were 0.7 (range: 0.6–0.9) and 0.27 (range: 0.22–0.32), respectively. The median LHR and o/e LHR after FETO were 1.2 (range: 0.9–1.8) and 0.45 (0.31–0.67), respectively. The median GA at FETO, reversal of TO and birth were 26.8 (range: 26–29), 32.5 (range: 31.0–34.0) and 37 weeks (range: 35–37), respectively. Neonatal survival at the time of hospital discharge was 50% (4/8). Conclusion: FETO is feasible at our institution and may help to improve postnatal survival of children with severe CDH in developing countries.

Birth‐weight prediction by two‐ and three‐dimensional ultrasound imaging

To compare the accuracies of birth‐weight predicting models derived from two‐dimensional (2D) ultrasound parameters and from total fetal thigh volumes measured by three‐dimensional (3D) ultrasound imaging; and to compare the performances of these formulae with those of previously published equations.

Intervalos de referência longitudinais de parâmetros doplervelocimétricos materno-fetais

PURPOSE To create longitudinal reference intervals for pulsatility index (PI) of the umbilical (UA), middle cerebral (MCA), uterine (UtA) arteries and ductus venosus (DV) in a Brazilian cohort. METHODS A longitudinal observational study performed from February 2010 to May 2012. Low risk pregnancies were scanned fortnightly from 18 to 40 weeks for the measurements of PI of the UA, MCA, DV and UtA. Linear mixed models were used for the elaboration of longitudinal reference intervals (5th, 50th and 95th percentiles) of these measurements. PI obtained for the placental and abdominal portions of the umbilical artery were compared by the t-test for independent samples. Two-sided p values of less than 0.05 were considered statistically significant. RESULTS A total of 164 patients underwent 1,242 scans. There was significant decrease in PI values of all vessels studied with gestational age (GA). From the 18(th) to the 40(th) week of pregnancy, the median PI values of UA (abdominal and placental ends of the cord), MCA, DV and the mean PI of the UtA ranged from 1.19 to 0.74, 1.33 to 0.78, 1.56 to 1.39, 0.58 to 0.41, and 0.98 to 0.66, respectively. The following equations were obtained for the prediction of the medians: PI-UA=1.5602786 - (0.020623 x GA); Logarithm of the PI-MCA=0.8149111 - (0.004168 x GA) - [0.02543 x (GA - 28.7756)²]; Logarithm of the PI-DV=-0.26691- (0.015414 x GA); PI-UtA = 1.2362403 - (0.014392 x GA). There was a significant difference between the PI-UA obtained at the abdominal and placental ends of the umbilical cord (p<0.001). CONCLUSIONS Longitudinal reference intervals for the main gestational Doppler parameters were obtained in a Brazilian cohort. These intervals could be more adequate for the follow-up of maternal-fetal hemodynamic modifications in normal and abnormal pregnancies, a fact that still requires further validation.

Balloon removal after fetoscopic endoluminal tracheal occlusion for congenital diaphragmatic hernia

BACKGROUND: Isolated congenital diaphragmatic hernia defect allows viscera to herniate into the chest, competing for space with the developing lungs. At birth, pulmonary hypoplasia leads to respiratory insufficiency and persistent pulmonary hypertension that is lethal in up to 30% of patients. Antenatal measurement of lung size and liver herniation can predict survival after birth. Prenatal intervention aims at stimulating lung development, clinically achieved by percutaneous fetal endoscopic tracheal occlusion under local anesthesia. This in utero treatment requires a second intervention to reestablish the airway, either before birth or at delivery. OBJECTIVE: To describe our experience with in utero endotracheal balloon removal. MATERIALS AND METHODS: This is a retrospective analysis of prospectively collected data on consecutive patients with congenital diaphragmatic hernia treated in utero by fetal endoscopic tracheal occlusion from 3 centers. Maternal and pregnancy‐associated variables were retrieved. Balloon removal attempts were categorized as elective or emergency and by technique (in utero: ultrasound‐guided puncture; fetoscopy; ex utero: on placental circulation or postnatal tracheoscopy). RESULTS: We performed 351 balloon insertions during a 144‐month period. In 9 cases removal was attempted outside fetal endoscopic tracheal occlusion centers, 3 of which were deemed impossible and led to neonatal death. We attempted 302 in‐house balloon removals in 292 fetuses (217 elective [71.8%], 85 emergency [28.2%]) at 33.4 ± 0.1 weeks (range: 28.9−37.1), with a mean interval to delivery of 16.6 ± 0.8 days (0‐85). Primary attempt was by fetoscopy in 196 (67.1%), by ultrasound‐guided puncture in 62 (21.2%), by tracheoscopy on placental circulation in 30 (10.3%), and postnatal tracheoscopy in 4 cases (1.4%); a second attempt was required in 10 (3.4%) cases. Each center had different preferences for primary technique selection. In elective removals, we found no differences in the interval to delivery between fetoscopic and ultrasound‐guided puncture removals. Difficulties during fetoscopic removal led to the development of a stylet to puncture the balloon, leading to shorter operating time and easier reestablishment of airways. CONCLUSION: In these fetal treatment centers, the balloon could always be removed successfully. In 90% this was in utero, with the use of fetoscopy preferred over ultrasound‐guided puncture. Ex utero removal was a fall‐back procedure. In utero removal does not seem to precipitate immediate membrane rupture, labor, or delivery, although the design of the study did not allow for a formal conclusion. For fetoscopic removals, the introduction of a stylet facilitated retrieval. Successful removal may rely on a permanently prepared team with expertise in all possible techniques.

Endoscopic laser dichorionization of the placenta in the treatment of severe twin-twin transfusion syndrome.

Objectives: To describe the results of a technique of laser ablation of placental vessels in the treatment of severe twin-twin transfusion syndrome (TTTS), which is characterized by separation of the fetoplacental vascular territories and dichorionization of the placenta. Patients and Methods: Descriptive analysis of TTTS cases treated with the endoscopic laser dichorionization of the placenta (ELDP) procedure. The variables evaluated were the occurrence of reversal of the donor-recipient phenotype, persistence of TTTS or twin anemia-polycythemia sequence (TAPS); gestational age at delivery; discharge from the hospital of at least 1 or 2 live neonates, and incidence of neurological alterations among survivors. Results: 67 patients were treated with the ELDP procedure. There was no persistence of TTTS, reversal of the donor-recipient phenotype or TAPS. The median gestational age at delivery was 33.0 (23.6-37.7) weeks. The rate of discharge from the hospital of at least 1 or 2 live neonates was 88.2% (67/76) and 71.1% (54/76), respectively. Among survivors, 17 (17/121 = 14.0%) children presented with neurodevelopmental alterations during clinical follow-up. Conclusions: The major contribution of this study was the demonstration that the ELDP technique appears to be associated with a low risk of persistence or recurrence of TTTS and TAPS.

Laser ablation of placental vessels for treatment of severe twin-twin transfusion syndrome: experience from an university center in Brazil

PURPOSE To describe the results of laser ablation of placental vessels for the treatment of severe twin-to-twin transfusion syndrome in an university center in Brazil. METHODS Retrospective observational study of patients treated at UNICAMP from 2007 to 2009. Laser ablation of placental vessels was performed in cases of severe twin-twin transfusion syndrome (Quintero stages II, III and IV) diagnosed before 26 complete weeks of gestation. The main variables evaluated in this series were gestational age at delivery, survival (discharge from the nursery) of at least one twin and neurological damage in survivors. Logistic regression was used to investigate the influence of cervical length, gestational age and stage of the disease (before the surgery) on the occurrence of delivery/abortion and fetal death after the intervention, and the influence on severe preterm birth and survival. RESULTS In the whole series, at least one twin survived in 63.3% of cases (19/30). Among patients who did not have delivery/abortion after surgery, the survival of at least one twin was 82.6% (19/23). In this subgroup (n=23), mean gestational age in delivery was 31.9 weeks and neurological damage was identified in one neonate (1/31; 3.2%). Cervix length influenced the occurrence of delivery/abortion after surgery (p-value=0.008). Among seven patients (7/30; 23.3%) who carried this complication, five (5/7; 71.4%) had cervix length lower than 15 mm. Among the 23 patients who did not have delivery/abortion as a result of the surgery, the highest stages of the disease (III and IV) increased the risk of delivery prior to 32 complete weeks of gestation (p-value=0.025) and decreased the chance of survival of both twins (p-value=0.026). CONCLUSIONS The results are similar to those available in the literature. In our series, the main factors associated with poorer results were short cervix (lower than 15 mm) and the highest stages of the disease (III and IV) at the time of the treatment.

Oclusão traqueal para fetos com hérnia diafragmática esquerda grave isolada: um estudo experimental controlado não randomizado

PURPOSE To compare postnatal survival to hospital discharge of fetuses with severe isolated left-sided congenital diaphragmatic hernia, who underwent tracheal occlusion, with that of nonrandomized contemporaneous controls. METHODS Experimental nonrandomized controlled study, performed from April 2007 to September 2011. Fetuses with severe isolated left-sided congenital diaphragmatic hernia with liver herniation into the chest and lung area-to-head circumference ratio <1.0, who underwent tracheal occlusion (study group) or expectant management (non-randomized contemporaneous controls), were compared in terms of lung area-to-head circumference ratio and observed/expected lung area-to-head circumference ratio (observed/expected lung area-to-head circumference ratio) at the time of diagnosis, gestational age at birth, and survival to hospital discharge. Modifications in lung area-to-head circumference ratio and o/e lung area-to-head circumference ratio after tracheal occlusion were also analyzed. Fishers exact test, Mann-Whitneys or Wilcoxons tests were used for the comparisons. RESULTS There were no significant differences between the Study Group (TO=28) and Controls (n=13) in terms of the lung area-to-head circumference ratio (p=0.709) and the observed/expected lung area-to-head circumference ratio (p=0.5) at the time of diagnosis and gestational age at birth (p=0.146). The survival to hospital discharge was higher (p=0.012) in the tracheal occlusion group (10/28=35.7%) than in controls (0/13=0.0%). There was a significant increase in lung area-to-head circumference ratio (p<0.001) and observed/expected lung area-to-head circumference ratio (p<0.001) between the diagnosis of the congenital diaphragmatic hernia [lung area-to-head circumference ratio: 0.80 (0.40-0.94); observed/expected lung area-to-head circumference ratio: 27.0 (15.3-45.0)], and the day before retrieval of the balloon [lung area-to-head circumference ratio: 1.2 (0.50-1.80); observed/expected lung area-to-head circumference ratio: 40.0 (17.5-60.0)]. CONCLUSIONS There was a significant improvement in the survival rate to hospital discharge of fetuses with severe isolated left-sided congenital diaphragmatic hernia, who underwent tracheal occlusion in comparison to nonrandomized contemporaneous controls.

Longitudinal reference intervals for Doppler velocimetric parameters of the fetal renal artery correlated with amniotic fluid index among low-risk pregnancies

To establish longitudinal reference intervals for pulsatility index (PI) and systolic velocity (SV) of the fetal renal artery, and to evaluate their correlation with the amniotic fluid index (AFI).

Fetal growth standards in gastroschisis: Reference values for ultrasound measurements

The objectives of this study were to create growth curves based on ultrasonography biometric parameters of fetuses with gastroschisis, comparing them with normal growth standards, and to analyze umbilical artery (UA) Doppler velocimetry patterns.

Elaboração e validação de intervalos de referência longitudinais de peso fetal com uma amostra da população brasileira

PURPOSES To elaborate models for the estimation of fetal weight and longitudinal reference intervals of estimated fetal weight (EFW) using a sample of the Brazilian population. METHODS Prospective observational study. Two groups of patients were evaluated: Group EFW (estimation of fetal weight): to elaborate (EFW-El) and validate (EFW-Val) a model for the prediction of fetal weight; Group LRI (longitudinal reference intervals): To elaborate (LRI-El) and validate (LRF-Val) conditional (longitudinal) percentiles of EFW. Polynomial regression analysis was applied to the data from subgroup EFW-El to elaborate a model for the estimation of fetal weight. The performance of this model was compared to those of previously published formulas. Linear mixed models were used for the elaboration of longitudinal reference intervals of EFW using data from subgroup LRI-El. Data obtained from subgroup LRI-Val were used to validate these intervals. RESULTS Group EFW consisted of 458 patients (EFW-El: 367; EFW-Val: 91) and Group LRI consisted of 315 patients (LRI-El: 265; LRI-Val: 50). The model obtained for EFW was: EFW=-8.277+2.146xBPDxACxFL-2.449xFLxBPD². The performances of other models were significantly worse than those obtained with our formula. Equations for the prediction of conditional percentiles of EFW were derived from the longitudinal observation of patients of subgroup LRI-El and validated with data from subgroup LRI-Val. CONCLUSIONS We described a method for customization of longitudinal reference intervals of EFW obtained using formulas generated from a sample of the Brazilian population.