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1.
Ultrasound Obstet Gynecol ; 63(4): 446-456, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38197327

RESUMO

OBJECTIVE: To determine the diagnostic accuracy of prenatal ultrasound in detecting coarctation of the aorta (CoA). METHODS: An individual participant data meta-analysis was performed to report on the strength of association and diagnostic accuracy of different ultrasound signs in detecting CoA prenatally. MEDLINE, EMBASE and CINAHL were searched for studies published between January 2000 and November 2021. Inclusion criteria were fetuses with suspected isolated CoA, defined as ventricular and/or great vessel disproportion with right dominance on ultrasound assessment. Individual participant-level data were obtained by two leading teams. PRISMA-IPD and PRISMA-DTA guidelines were used for extracting data, and the QUADAS-2 tool was used for assessing quality and applicability. The reference standard was CoA, defined as narrowing of the aortic arch, diagnosed after birth. The most commonly evaluated parameters on ultrasound, both in B-mode and on Doppler, constituted the index test. Summary estimates of sensitivity, specificity, diagnostic odds ratio (DOR) and likelihood ratios were computed using the hierarchical summary receiver-operating-characteristics model. RESULTS: The initial search yielded 72 studies, of which 25 met the inclusion criteria. Seventeen studies (640 fetuses) were included. On random-effects logistic regression analysis, tricuspid valve/mitral valve diameter ratio > 1.4 and > 1.6, aortic isthmus/arterial duct diameter ratio < 0.7, hypoplastic aortic arch (all P < 0.001), aortic isthmus diameter Z-score of < -2 in the sagittal (P = 0.003) and three-vessel-and-trachea (P < 0.001) views, pulmonary artery/ascending aorta diameter ratio > 1.4 (P = 0.048) and bidirectional flow at the foramen ovale (P = 0.012) were independently associated with CoA. Redundant foramen ovale was inversely associated with CoA (P = 0.037). Regarding diagnostic accuracy, tricuspid valve/mitral valve diameter ratio > 1.4 had a sensitivity of 72.6% (95% CI, 48.2-88.3%), specificity of 65.4% (95% CI, 46.9-80.2%) and DOR of 5.02 (95% CI, 1.82-13.9). The sensitivity and specificity values were, respectively, 75.0% (95% CI, 61.1-86.0%) and 39.7% (95% CI, 27.0-53.4%) for pulmonary artery/ascending aorta diameter ratio > 1.4, 47.8% (95% CI, 14.6-83.0%) and 87.6% (95% CI, 27.3-99.3%) for aortic isthmus diameter Z-score of < -2 in the sagittal view and 74.1% (95% CI, 58.0-85.6%) and 62.0% (95% CI, 41.6-78.9%) for aortic isthmus diameter Z-score of < -2 in the three-vessel-and-trachea view. Hypoplastic aortic arch had a sensitivity of 70.0% (95% CI, 42.0-88.6%), specificity of 91.3% (95% CI, 78.6-96.8%) and DOR of 24.9 (95% CI, 6.18-100). The diagnostic yield of prenatal ultrasound in detecting CoA did not change significantly when considering multiple categorical parameters. Five of the 11 evaluated continuous parameters were independently associated with CoA (all P < 0.001) but all had low-to-moderate diagnostic yield. CONCLUSIONS: Several prenatal ultrasound parameters are associated with an increased risk for postnatal CoA. However, diagnostic accuracy is only moderate, even when combinations of parameters are considered. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Coartação Aórtica , Canal Arterial , Gravidez , Feminino , Humanos , Coartação Aórtica/diagnóstico por imagem , Ultrassonografia Pré-Natal , Aorta/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Canal Arterial/diagnóstico por imagem , Estudos Retrospectivos
2.
Artigo em Inglês | MEDLINE | ID: mdl-37689502

RESUMO

INTRODUCTION AND AIM: Endoscopic retrograde cholangiopancreatography (ERCP) is a complex procedure. Clinical guidelines assess competence in ERCP through a defined number of procedures, but multiple factors are involved. Our aim was to analyze the morphology of the papilla of Vater as an independent factor in selective common bile duct cannulation during resident training. MATERIAL AND METHODS: Patients that underwent ERCP were studied consecutively. All ERCPs were begun by a resident in training. The type of papilla was classified according to Haraldsson, including those with previous sphincterotomy. Cannulation difficulty and success and their relation to the type of papilla were documented. The analysis was divided into three 4-month periods. RESULTS: Of the 429 patients, cannulation was difficult in 101 (23.5%). The residents achieved selective cannulation of the common bile duct in 276 (64.3%) and the cannulation success rate at the end of their training was 81.7%. Cannulation was performed with the least difficulty in papillae with previous sphincterotomy (2.8%), unlike the type 4 papilla, which was difficult to cannulate in 50% of the cases. The lowest overall cannulation success was in the type 2 papilla (81.8%). CONCLUSION: Papilla type can influence cannulation success, but it is not the only related factor. Patients that underwent previous sphincterotomy appear to be the cases in whom ERCP training can be started.

3.
Ultrasound Obstet Gynecol ; 62(6): 788-795, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37325877

RESUMO

OBJECTIVE: To develop a model for the prediction of adverse perinatal outcome in growth-restricted fetuses requiring delivery before 28 weeks in order to provide individualized patient counseling. METHODS: This was a retrospective multicenter cohort study of singleton pregnancies with antenatal suspicion of fetal growth restriction requiring delivery before 28 weeks' gestation between January 2010 and January 2020 in six tertiary public hospitals in the Barcelona area, Spain. Separate predictive models for mortality only and mortality or severe neurological morbidity were created using logistic regression from variables available antenatally. For each model, predictive performance was evaluated using receiver-operating-characteristics (ROC)-curve analysis. Predictive models were validated externally in an additional cohort of growth-restricted fetuses from another public tertiary hospital with the same inclusion and exclusion criteria. RESULTS: A total of 110 cases were included. The neonatal mortality rate was 37.3% and, among the survivors, the rate of severe neurological morbidity was 21.7%. The following factors were retained in the multivariate analysis as significant predictors of mortality: magnesium sulfate neuroprotection, gestational age at birth, estimated fetal weight, male sex and Doppler stage. This model had a significantly higher area under the ROC curve (AUC) compared with a model including only gestational age at birth (0.810 (95% CI, 0.730-0.889) vs 0.695 (95% CI, 0.594-0.795); P = 0.016). At a 20% false-positive rate, the model showed a sensitivity, negative predictive value and positive predictive value of 66%, 80% and 66%, respectively. For the prediction of the composite adverse outcome (mortality or severe neurological morbidity), the model included: gestational age at birth, male sex and Doppler stage. This model had a significantly higher AUC compared with a model including only gestational age at birth (0.810 (95% CI, 0.731-0.892) vs 0.689 (95% CI, 0.588-0.799); P = 0.017). At a 20% false-positive rate, the model showed a sensitivity, negative predictive value and positive predictive value of 55%, 63% and 74%, respectively. External validation of both models yielded similar AUCs that did not differ significantly from those obtained in the original sample. CONCLUSIONS: Estimated fetal weight, fetal sex and Doppler stage can be combined with gestational age to improve the prediction of death or severe neurological sequelae in growth-restricted fetuses requiring delivery before 28 weeks. This approach may be useful for parental counseling and decision-making. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Peso Fetal , Recém-Nascido Pequeno para a Idade Gestacional , Recém-Nascido , Gravidez , Feminino , Masculino , Humanos , Estudos de Coortes , Lactente Extremamente Prematuro , Ultrassonografia Pré-Natal , Retardo do Crescimento Fetal/diagnóstico por imagem , Idade Gestacional , Morbidade , Feto
4.
Ultrasound Obstet Gynecol ; 62(1): 14-22, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36776132

RESUMO

OBJECTIVE: A favorable postnatal prognosis in cases of pulmonary atresia/critical stenosis with intact ventricular septum (PA/CS-IVS) is generally equated with the possibility of achieving biventricular (BV) repair. Identification of fetuses that will have postnatal univentricular (UV) circulation is key for prenatal counseling, optimization of perinatal care and decision-making regarding fetal therapy. We aimed to evaluate the accuracy of published models for predicting postnatal circulation in PA/CS-IVS using a large internationally derived validation cohort. METHODS: This was a systematic review of published uni- and multiparametric models for the prediction of postnatal circulation based on echocardiographic findings at between 20 and 28 weeks of gestation. Models were externally validated using data from the International Fetal Cardiac Intervention Registry. Sensitivity, specificity, predictive values, area under the receiver-operating-characteristics curves (AUCs) and proportion of cases with true vs predicted outcome were calculated. RESULTS: Eleven published studies that reported prognostic parameters of postnatal circulation were identified. Models varied widely in terms of the main outcome (UV (n = 3), non-BV (n = 3), BV (n = 3), right-ventricle-dependent coronary circulation (n = 1) or tricuspid valve size at birth (n = 1)) and in terms of the included predictors (single parameters only (n = 6), multiparametric score (n = 4) or both (n = 1)), and were developed on small sample sizes (range, 15-38). Nine models were validated externally given the availability of the required parameters in the validation cohort. Tricuspid valve diameter Z-score, tricuspid regurgitation, ratios between right and left cardiac structures and the presence of ventriculocoronary connections (VCC) were the most commonly evaluated parameters. Multiparametric models including up to four variables (ratios between right and left structures, right ventricular inflow duration, presence of VCC and tricuspid regurgitation) had the best performance (AUC, 0.80-0.89). Overall, the risk of UV outcome was underestimated and that of BV outcome was overestimated by most models. CONCLUSIONS: Current prenatal models for the prediction of postnatal outcome in PA/CS-IVS are heterogeneous. Multiparametric models for predicting UV and non-BV circulation perform well in identifying BV patients but have low sensitivity, underestimating the rate of fetuses that will ultimately have UV circulation. Until better discrimination can be achieved, fetal interventions may need to be limited to only those cases in which non-BV postnatal circulation is certain. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Atresia Pulmonar , Insuficiência da Valva Tricúspide , Septo Interventricular , Gravidez , Recém-Nascido , Feminino , Humanos , Atresia Pulmonar/diagnóstico por imagem , Constrição Patológica , Estudos Retrospectivos
5.
Ultrasound Obstet Gynecol ; 61(2): 168-180, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35816445

RESUMO

Pre-eclampsia (PE) is characterized by placental and maternal endothelial dysfunction, and associated with fetal growth restriction (FGR), placental abruption, preterm delivery and stillbirth. The angiogenic factors soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) are altered in pregnancies complicated by placenta-related disorders. In this Review, we summarize the existing knowledge, examining the performance of maternal PlGF, sFlt-1 and the sFlt-1/PlGF ratio for screening PE, predicting development of PE in the short term, diagnosing PE, monitoring established PE and predicting other placenta-related disorders in singleton pregnancy. We also discuss the performance of PlGF and the sFlt-1/PlGF ratio for predicting PE in twin pregnancy. For first-trimester screening in singleton pregnancy, a more accurate way of identifying high-risk women than current practice is to combine maternal PlGF levels with clinical risk factors and ultrasound markers. Later in pregnancy, the sFlt-1/PlGF ratio has advantages over PlGF because it has a higher pooled sensitivity and specificity for diagnosing and monitoring PE. It has clinical value because it can rule out the development of PE in the 1-4-week period after the test. Once a diagnosis of PE is established, repeat measurement of sFlt-1 and PlGF can help monitor progression of the condition and may inform clinical decision-making regarding the optimal time for delivery. The sFlt-1/PlGF ratio is useful for predicting FGR and preterm delivery, but the association between stillbirth and the angiogenic factors is unclear. The sFlt-1/PlGF ratio can be used to predict PE in twin pregnancy, although different sFlt-1/PlGF ratio cut-offs from those for singleton pregnancy should be applied for optimal performance. In summary, PlGF, sFlt-1 and the sFlt-1/PlGF ratio are useful for screening, diagnosing, predicting and monitoring placenta-related disorders in singleton and twin pregnancy. We propose that tests for these angiogenic factors are integrated more fully into clinical practice.© 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Pré-Eclâmpsia , Nascimento Prematuro , Recém-Nascido , Gravidez , Feminino , Humanos , Fator de Crescimento Placentário , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/metabolismo , Retardo do Crescimento Fetal/diagnóstico , Natimorto , Valor Preditivo dos Testes , Biomarcadores , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Placenta/metabolismo , Fator A de Crescimento do Endotélio Vascular
6.
Biomech Model Mechanobiol ; 22(2): 575-591, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36550245

RESUMO

BACKGROUND: Aortic Regurgitation (AR) produces the entrance of an abnormal amount of blood in the left ventricle. This disease is responsible for high morbidity and mortality worldwide and may be caused by an aortic valve dysfunction. Surgical and transcatheter aortic valve replacement (TAVR) are the current options for treating AR. They have replaced older procedures such as Hufnagel's one. However, some physicians have reconsidered this procedure as a less aggressive alternative for patients not eligible for surgical or TAVR. Although Hufnagel suggested a 75% regurgitation reduction when a valve is placed in the descending aorta, a quantification of this value has not been reported. METHODS: In this paper, CFD/FSI numerical simulation is conducted on an idealized geometry. We quantify the effect of placing a bileaflet mechanical heart valve in the descending aorta on a moderate-severe AR case. A three-element Windkessel model is employed to prescribe pressure outlet boundary conditions. We calculate the resulting flow rates and pressures at the aorta and first-generation vessels. Moreover, we evaluate several indices to assess the improvement due to the valve introduction. RESULTS AND CONCLUSIONS: Regurgitation fraction (RF) is reduced from 37.5% (without valve) to 18.0% (with valve) in a single cardiac cycle. This reduction clearly shows the remarkable efficacy of the rescued technique. It will further ameliorate the left ventricle function in the long-term. Moreover, the calculations show that the implantation in that location introduces fewer incompatibilities' risks than a conventional one. The proposed methodology can be extended to any particular conditions (pressure waveforms/geometry) and is designed to assess usual clinical parameters employed by physicians.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Insuficiência da Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/etiologia , Aorta Torácica/cirurgia , Valva Aórtica/cirurgia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Próteses Valvulares Cardíacas/efeitos adversos , Resultado do Tratamento , Fatores de Risco
7.
Ultrasound Obstet Gynecol ; 61(2): 181-190, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36370447

RESUMO

OBJECTIVE: To analyze the ability to predict perinatal survival and severe neonatal morbidity of cases with early-onset fetal growth restriction (eoFGR) using maternal variables, ultrasound parameters and angiogenic markers at the time of diagnosis. METHODS: This was a prospective observational study in a cohort of singleton pregnancies with a diagnosis of eoFGR (< 32 weeks of gestation). At diagnosis of eoFGR, complete assessment was performed, including ultrasound examination (anatomy, biometry and Doppler assessment) and maternal serum measurement of the angiogenic biomarkers, soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF). Logistic regression models for the prediction of perinatal survival (in cases diagnosed at < 28 weeks) and severe neonatal morbidity (in all liveborn cases) were calculated. RESULTS: In total, 210 eoFGR cases were included, of which 185 (88.1%) survived perinatally. The median gestational age at diagnosis was 27 + 0 weeks. All cases diagnosed at ≥ 28 weeks survived. In cases diagnosed < 28 weeks, survivors (vs non-survivors) had a higher gestational age (26.1 vs 24.4 weeks), estimated fetal weight (EFW; 626 vs 384 g), cerebroplacental ratio (1.1 vs 0.9), PlGF (41 vs 18 pg/mL) and PlGF multiples of the median (MoM; 0.10 vs 0.06) and lower sFlt-1/PlGF ratio (129 vs 479) at the time of diagnosis (all P < 0.001). The best combination of two variables for predicting perinatal survival was provided by EFW and PlGF MoM (area under the receiver-operating-characteristics curve (AUC), 0.84 (95% CI, 0.75-0.92)). These were also the best variables for predicting severe neonatal morbidity (AUC, 0.73 (95% CI, 0.66-0.80)). CONCLUSIONS: A model combining EFW and maternal serum PlGF predicts accurately perinatal survival in eoFGR cases diagnosed before 28 weeks of gestation. Prenatal prediction of severe neonatal morbidity in eoFGR cases is modest regardless of the model used. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Retardo do Crescimento Fetal , Recém-Nascido Pequeno para a Idade Gestacional , Gravidez , Recém-Nascido , Feminino , Humanos , Lactente , Fator de Crescimento Placentário , Retardo do Crescimento Fetal/diagnóstico por imagem , Valor Preditivo dos Testes , Cuidado Pré-Natal , Biomarcadores , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Ultrassonografia Pré-Natal
8.
Brain Stimul ; 15(5): 1184-1191, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36028155

RESUMO

BACKGROUND: Treatment-refractory psychosis (TRP) is a significant clinical challenge. While clozapine is frequently effective, alternate or augmentation strategies are often necessary. Evidence supports effectiveness of electroconvulsive therapy (ECT), but questions remain about optimal treatment parameters and impacts of concomitant pharmacotherapy. OBJECTIVE: /Hypothesis: To analyze the impact of clozapine, anticonvulsant medication, mood state, and ECT electrode placement on outcomes in TRP. We hypothesized that ECT would lead to greater reduction in positive symptoms, particularly in patients receiving clozapine. METHODS: Retrospective study in a tertiary TRP program. The Positive and Negative Syndrome Scale (PANSS) was used for clinical outcomes, with positive subscore as primary outcome. Clinical and ECT data were analyzed using a linear modelling approach, controlling for relevant covariates. RESULTS: A total of 309 patients were included. ECT plus clozapine associated with greater improvement in positive, general, and total symptoms than ECT alone. ECT associated with greater improvement in negative symptoms in depressed patients. Bifrontal placement was mostly equivalent to bitemporal, with greater reduction of positive symptoms in patients receiving clozapine, and associated with lower electrical dose in patients on anticonvulsants. Clozapine increased seizure duration, while anticonvulsants decreased it. Anticonvulsant use in ECT patients associated with equivalent to slightly improved symptom reduction. CONCLUSIONS: ECT's benefit in TRP may be greatest in patients receiving clozapine. ECT can improve negative symptoms in depressed TRP patients. Bifrontal placement is effective in TRP. Clozapine and anticonvulsants have opposite effects on seizure duration, but anticonvulsants may not adversely affect clinical outcomes of ECT for TRP.


Assuntos
Antipsicóticos , Clozapina , Eletroconvulsoterapia , Transtornos Psicóticos , Esquizofrenia , Anticonvulsivantes/uso terapêutico , Antipsicóticos/uso terapêutico , Clozapina/uso terapêutico , Eletroconvulsoterapia/efeitos adversos , Eletrodos , Humanos , Transtornos Psicóticos/terapia , Estudos Retrospectivos , Esquizofrenia/terapia , Convulsões , Resultado do Tratamento
9.
Med. intensiva (Madr., Ed. impr.) ; 46(8): 446-454, ago. 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-207874

RESUMO

La evolución del tratamiento de oxigenación por membrana extracorpórea (ECMO) y en particular del transporte de los pacientes sometidos a él, ha cambiado de forma significativa en la última década y lo ha hecho de manera desigual en diferentes regiones. Se ha demostrado que la creación de centros de referencia especializados mejora los resultados. Por todo ello ha sido necesario crear redes de equipos especializados y el número de transportes secundarios de pacientes con este tratamiento está en aumento. Con el fin de mejorar la calidad del tratamiento y ofrecer una guía para los servicios que intervienen en estos transportes, los grupos de trabajo de transporte crítico de la Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias (SEMICYUC) y la Sociedad Española de Cuidados Intensivos Pediátricos (SECIP) han realizado un trabajo conjunto de elaboración de estas recomendaciones, enfocadas a los siguientes aspectos: indicaciones, sistemas de centros de referencia, medios de transporte, características y equipamiento, equipos humanos, formación y seguridad clínica (AU)


The evolution of extracorporeal membrane oxygenation treatment and the transport of patients receiving this treatment has changed dramatically in the last decade unevenly in different regions. The creation of specialized referral centers has been shown to improve outcomes. For all these reasons, it has been necessary to create networks of specialized teams and the number of secondary transports of patients with this treatment is increasing. In order to improve the quality of treatment and offer a guide to the services involved in these transports, the critical transport working groups of the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC) and the Spanish Society of Pediatric Intensive Care (SECIP) have carried out a joint effort to prepare these recommendations, focused on the following aspects: indications, reference center systems, means of transport, characteristics and equipment, human teams, training and clinical safety (AU)


Assuntos
Humanos , Oxigenação por Membrana Extracorpórea , Cuidados Críticos , Transporte de Pacientes/métodos , Sociedades Médicas , Consenso , Espanha
10.
Med Intensiva (Engl Ed) ; 46(8): 446-454, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35752606

RESUMO

The evolution of extracorporeal membrane oxygenation treatment and the transport of patients receiving this treatment has changed dramatically in the last decade unevenly in different regions. The creation of specialized referral centers has been shown to improve outcomes. For all these reasons, it has been necessary to create networks of specialized teams and the number of secondary transports of patients with this treatment is increasing. In order to improve the quality of treatment and offer a guide to the services involved in these transports, the critical transport working groups of the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC) and the Spanish Society of Pediatric Intensive Care (SECIP) have carried out a joint effort to prepare these recommendations, focused on the following aspects: indications, reference center systems, means of transport, characteristics and equipment, human teams, training and clinical safety.


Assuntos
Oxigenação por Membrana Extracorpórea , Criança , Consenso , Cuidados Críticos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Humanos
11.
J Chem Phys ; 156(15): 154111, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35459323

RESUMO

The link between the static dielectric constant and the microscopic intermolecular interactions is the Kirkwood g1 factor, which depends on the orientational structure of the fluid. Over the years, there have been several attempts to provide an accurate description of the orientational structure of dipolar fluids using molecular theories. However, these approaches were either limited to mean-field approximations for the pair correlation function or, more recently, limited to adjusting the orientational dependence to simulation data. Here, we derive a theory for the dielectric constant of dipolar hard-sphere fluids using the augmented modified mean-field approximation. Qualitative agreement is achieved throughout all relevant thermodynamic states, as demonstrated by a comparison with simulation data from the literature. Excellent quantitative agreement can be obtained using a single empirical scaling factor, the physical origin of which is analyzed and accounted for. In order to predict the dielectric constant of the Stockmayer fluid (Lennard-Jones plus dipole potential), we use an adjusted version of the expression for the dipolar hard-sphere fluid. Comparing theoretical predictions with newly generated simulation data, we show that it is possible to obtain excellent agreement with simulation by performing the calculations at a corresponding state using the same scaling factor. Finally, we compare the theoretical orientational structure of the Stockmayer fluid with that obtained from simulations. The simulated structure is calculated following a post-processing methodology that we introduce by deriving an original expression that relates the proposed theory to the histogram of relative dipole angles.

12.
Ultrasound Obstet Gynecol ; 57(5): 687-697, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33724545

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a zoonotic coronavirus that crossed species to infect humans, causing coronavirus disease 2019 (COVID-19). Despite a potentially higher risk of pregnant women acquiring SARS-CoV-2 infection compared with the non-pregnant population (particularly in some ethnic minorities), no additional specific recommendations to avoid exposure are needed in pregnancy. The most common clinical symptoms and laboratory signs of SARS-CoV-2 infection in pregnancy are fever, cough, lymphopenia and elevated C-reactive protein levels. Pregnancy is associated with a higher risk of severe SARS-CoV-2 infection compared with the non-pregnant population, including pneumonia, admission to the intensive care unit and death, even after adjusting for potential risk factors for severe outcomes. The risk of miscarriage does not appear to be increased in women with SARS-CoV-2 infection. Evidence with regards to preterm birth and perinatal mortality is conflicting, but these risks are generally higher only in symptomatic, hospitalized women. The risk of vertical transmission, defined as the transmission of SARS-CoV-2 from the mother to the fetus or the newborn, is generally low. Fetal invasive procedures are considered to be generally safe in pregnant women with SARS-CoV-2 infection, although the evidence is still limited. In pregnant women with COVID-19, use of steroids should not be avoided if clinically indicated; the preferred regimen is a 2-day course of dexamethasone followed by an 8-day course of methylprednisolone. Non-steroidal anti-inflammatory drugs may be used if there are no contraindications. Hospitalized pregnant women with severe COVID-19 should undergo thromboprophylaxis throughout the duration of hospitalization and at least until discharge, preferably with low molecular weight heparin. Hospitalized women who have recovered from a period of serious or critical illness with COVID-19 should be offered a fetal growth scan about 14 days after recovery from their illness. In asymptomatic or mildly symptomatic women who have tested positive for SARS-CoV-2 infection at full term (i.e. ≥ 39 weeks of gestation), induction of labor might be reasonable. To date, there is no clear consensus on the optimal timing of delivery for critically ill women. In women with no or few symptoms, management of labor should follow routine evidence-based guidelines. Regardless of COVID-19 status, mothers and their infants should remain together and breastfeeding, skin-to-skin contact, kangaroo mother care and rooming-in throughout the day and night should be practiced, while applying necessary infection prevention and control measures. Many pregnant women have already undergone vaccination, mostly in the USA where the first reports show no significant difference in pregnancy outcomes in pregnant women receiving SARS-CoV-2 vaccination during pregnancy compared with the background risk. Vaccine-generated antibodies were present in the umbilical cord blood and breast milk samples of pregnant and lactating women who received the mRNA COVID-19 vaccine. Based on the available limited data on the safety of the COVID-19 vaccine in pregnancy, it seems reasonable to offer the option of vaccination to pregnant women after accurate counseling on the potential risk of a severe course of the disease and the unknown risk of fetal exposure to the vaccine. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Vacinas contra COVID-19/uso terapêutico , COVID-19/prevenção & controle , Aconselhamento/estatística & dados numéricos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Educação de Pacientes como Assunto/estatística & dados numéricos , Complicações Infecciosas na Gravidez/prevenção & controle , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez/epidemiologia
14.
J Neonatal Perinatal Med ; 13(3): 413-417, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31771073

RESUMO

BACKGROUND: Premature infants often require long-term indwelling intravascular catheters. Occasionally, catheters fracture and migrate into cardiovascular structures, risking perforation, infection, thrombosis, and interference with cardiac and valve function. This case series describes our experience with percutaneous retrieval of broken intravascular catheters. METHODS: A gooseneck micro-snare was used to retrieve fractured catheters in four premature infants, weighing between 840 and 1930 grams. RESULTS: All procedures were successful without complications. CONCLUSIONS: Gooseneck-snare retrieval of broken indwelling intravascular catheters can be performed safely and successfully in premature infants even those that weigh less than 1000 grams.


Assuntos
Cateterismo Periférico , Cateteres de Demora/efeitos adversos , Remoção de Dispositivo , Migração de Corpo Estranho , Dispositivos de Acesso Vascular/efeitos adversos , Cateterismo Periférico/instrumentação , Cateterismo Periférico/métodos , Remoção de Dispositivo/instrumentação , Remoção de Dispositivo/métodos , Ecocardiografia/métodos , Falha de Equipamento , Feminino , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/etiologia , Migração de Corpo Estranho/terapia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Doenças do Recém-Nascido/terapia , Recém-Nascido Prematuro , Masculino , Resultado do Tratamento
16.
Ultrasound Obstet Gynecol ; 56(4): 549-556, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31840879

RESUMO

OBJECTIVE: To analyze the value of the soluble fms-like tyrosine kinase-1/placental growth factor (sFlt-1/PlGF) ratio in predicting the time to delivery in early-onset fetal growth restriction (FGR) with preserved antegrade umbilical artery (UA) flow at diagnosis. METHODS: This was a prospective observational single-center cohort study of pregnancies with early-onset (< 32 + 0 weeks) FGR and antegrade UA flow, in which maternal serum sFlt-1/PlGF ratio was determined at diagnosis. FGR was defined as estimated fetal weight < 3rd centile or < 10th centile with UA pulsatility index > 95th centile, fetal middle cerebral artery pulsatility index < 5th centile or cerebroplacental ratio < 5th centile. The previously described sFlt-1/PlGF ratio cut-off value of 85 for facilitating the diagnosis of pre-eclampsia was assessed in the prediction of the need to deliver in < 1 week and ≥ 4 weeks. RESULTS: In total, 120 cases were included. There were 116 (96.7%) liveborn neonates and 108 (90.0%) perinatal survivors. Median (interquartile range (IQR)) gestational age at diagnosis of early-onset FGR was 27.1 (25.7-29.4) weeks. Median (IQR) sFlt-1/PlGF ratio at diagnosis was 196 (84-474). Ninety (75.0%) cases had a sFlt-1/PlGF ratio ≥ 85. Among pregnancies with a liveborn neonate, median (IQR) interval to delivery in the groups with sFlt-1/PlGF ratio < 85 and ≥ 85 was 41 (22-54) days and 11 (4-20) days, respectively (P < 0.01). The probability of having to deliver within 1 week after diagnosis was 0% and 35.6% in those with sFlt-1/PlGF ratio < 85 and ≥ 85, respectively (P = 0.03), and the probability of delaying delivery for ≥ 4 weeks was 72.4% and 19.5%, respectively (P < 0.01). CONCLUSION: sFlt-1/PlGF ratio < 85 at diagnosis of early-onset FGR with antegrade UA flow identifies a group of pregnancies in which the need to deliver within 1 week is very low and the interval to delivery is expected to be prolonged for ≥ 4 weeks in > 70% of cases. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Retardo do Crescimento Fetal/diagnóstico , Fator de Crescimento Placentário/sangue , Artérias Umbilicais/embriologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Biomarcadores/sangue , Feminino , Retardo do Crescimento Fetal/fisiopatologia , Peso Fetal , Idade Gestacional , Humanos , Nascido Vivo , Artéria Cerebral Média/embriologia , Artéria Cerebral Média/fisiopatologia , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Fluxo Pulsátil , Fatores de Tempo , Artérias Umbilicais/fisiopatologia
17.
BMC Pediatr ; 19(1): 326, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506079

RESUMO

BACKGROUND: Congenital heart disease (CHD) is the most prevalent congenital malformation affecting 1 in 100 newborns. While advances in early diagnosis and postnatal management have increased survival in CHD children, worrying long-term outcomes, particularly neurodevelopmental disability, have emerged as a key prognostic factor in the counseling of these pregnancies. METHODS: Eligible participants are women presenting at 20 to < 37 weeks of gestation carrying a fetus with CHD. Maternal/neonatal recordings are performed at regular intervals, from the fetal period to 24 months of age, and include: placental and fetal hemodynamics, fetal brain magnetic resonance imaging (MRI), functional echocardiography, cerebral oxymetry, electroencephalography and serum neurological and cardiac biomarkers. Neurodevelopmental assessment is planned at 12 months of age using the ages and stages questionnaire (ASQ) and at 24 months of age with the Bayley-III test. Target recruitment is at least 150 cases classified in three groups according to three main severe CHD groups: transposition of great arteries (TGA), Tetralogy of Fallot (TOF) and Left Ventricular Outflow Tract Obstruction (LVOTO). DISCUSSION: The results of NEURO-HEART study will provide the most comprehensive knowledge until date of children's neurologic prognosis in CHD and will have the potential for developing future clinical decisive tools and improving preventive strategies in CHD. TRIAL REGISTRATION: NCT02996630 , on 4th December 2016 (retrospectively registered).


Assuntos
Desenvolvimento Infantil , Ensaios Clínicos como Assunto , Cardiopatias Congênitas/complicações , Transtornos do Neurodesenvolvimento/etiologia , Biomarcadores/sangue , Ecocardiografia , Feminino , Idade Gestacional , Cardiopatias Congênitas/sangue , Humanos , Lactente , Imageamento por Ressonância Magnética , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Avaliação de Resultados em Cuidados de Saúde , Gravidez , Prognóstico , Estudos Prospectivos
18.
Materials (Basel) ; 12(5)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30823647

RESUMO

Ultrasound energy is a green and economically viable alternative to conventional techniques for surface modification of materials. The main benefits of this technique are the decrease of processing time and the amount of energy used. In this work, graphene nanoplatelets were treated with organic acids under ultrasonic radiation of 350 W at different times (30 and 60 min) aiming to modify their surface with functional acid groups and to improve the adsorption of uremic toxins. The modified graphene nanoplatelets were characterized by Fourier transform infrared spectroscopy (FT⁻IR), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The optimum time for modification with organic acids was 30 min. The modified nanoplatelets were tested as adsorbent material for uremic toxins using the equilibrium isotherms where the adsorption isotherm of urea was adjusted for the Langmuir model. From the solution, 75% of uremic toxins were removed and absorbed by the modified nanoplatelets.

19.
Sci Total Environ ; 653: 241-252, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30412869

RESUMO

Water scarcity has received global attention in the last decade as it challenges food security in arid and semi-arid regions, particularly in the Middle East and North Africa. This research assesses the possible alleviation of water scarcity by reducing the water footprint in crop production through the application of soil mulching and drip irrigation. The study is the first to do so at catchment scale, taking into account various crops, multi-cropping, cropping patterns, and spatial differences in climate, soil, and field management factors, using field survey and local data. The AquaCrop-OS model and the global water footprint assessment (WFA) standard were used to assess the green and blue water footprint (WF) of ten major crops in the Upper Litani Basin (ULB) in Lebanon. The blue water saving and blue water scarcity reduction under these two alternative practices were compared to the current situation. The results show that the WF of crop production is more sensitive to climate than soil type. The annual blue WF of summer crops was largest when water availability was lowest. Mulching reduced the blue WF by 3.6% and mulching combined with drip irrigation reduced it by 4.7%. The blue water saving from mulching was estimated about 6.3 million m3/y and from mulching combined with drip irrigation about 8.3 million m3/y. This is substantial but by far not sufficient to reduce the overall blue WF in summer to a sustainable level at catchment scale.

20.
J Matern Fetal Neonatal Med ; 32(19): 3300-3302, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29618241

RESUMO

Lung cancer during pregnancy is a very rare disease with less than 70 cases published to date. Information about specific lung cancer as adenocarcinoma is even more limited. Genetic techniques can detect oncogene mutations which seem to be more frequent among cases of lung cancer in pregnant women and could determine both the treatment and prognosis. We present a recent case seen at our hospital and a literature review.


Assuntos
Adenocarcinoma de Pulmão/terapia , Neoplasias Pulmonares/terapia , Complicações Neoplásicas na Gravidez/terapia , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adulto , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Quinase do Linfoma Anaplásico/genética , Crizotinibe/uso terapêutico , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico , Inibidores de Proteínas Quinases/uso terapêutico
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