Maternal, obstetric, and fetal Doppler characteristics in a high-risk population: prediction of adverse perinatal outcomes and of cesarean section due to intrapartum fetal compromise / Características maternas, obstétricas e do Doppler fetal em uma população de alto risco: predição de desfechos perinatais adversos e de cesariana por comprometimento fetal intraparto

Abstract Objective: To evaluate the capacity of fetal Doppler, maternal, and obstetric characteristics for the prediction of cesarean section due to intrapartum fetal compromise (IFC), a 5-min Apgar score < 7, and an adverse perinatal outcome (APO), in a high-risk population. Materials and Methods: This was a prospective cohort study involving 613 singleton pregnant women, admitted for labor induction or at the beginning of spontaneous labor, who underwent Doppler ultrasound within the last 72 h before delivery. The outcome measures were cesarean section due to IFC, a 5-min Apgar score < 7, and any APO. Results: We found that maternal characteristics were neither associated with nor predictors of an APO. Abnormal umbilical artery (UA) resistance index (RI) and the need for intrauterine resuscitation were found to be significant risk factors for cesarean section due to IFC (p = 0.03 and p < 0.0001, respectively). A UA RI > the 95th percentile and a cerebroplacental ratio (CPR) < 0.98 were also found to be predictors of cesarean section due to IFC. Gestational age and a UA RI > 0.84 were found to be predictors of a 5-min Apgar score < 7 for newborns at < 29 and ≥ 29 weeks, respectively. The UA RI and CPR presented moderate accuracy in predicting an APO, with areas under the ROC curve of 0.76 and 0.72, respectively. Conclusion: A high UA RI appears to be a significant predictor of an APO. The CPR seems to be predictive of cesarean section due to IFC and of an APO in late preterm and term newborns.

Resumo Objetivo: Avaliar a capacidade do Doppler fetal e características materno-obstétricas na predição de cesariana por comprometimento fetal intraparto (CFI), índice de Apgar de 5º min < 7 e desfecho perinatal adverso (DPA) em uma população de alto risco. Materiais e Métodos: Estudo de coorte prospectivo envolvendo 613 parturientes admitidas para indução ou em início de trabalho de parto espontâneo que realizaram ultrassonografia Doppler nas 72 horas anteriores ao parto. Os desfechos foram cesariana por CFI, índice de Apgar de 5º min < 7 e DPA. Resultados: As características maternas não foram associadas nem preditoras de DPA. Índice de resistência (IR) da artéria umbilical anormal (p = 0,03) e necessidade de medidas de ressuscitação intrauterina (p < 0,0001) permaneceram como fatores de risco significativos para cesariana por CFI. IR AU > 95º e razão cerebroplacentária (RCP) < 0,98 foram preditores de cesariana. Idade gestacional e IR AU > 0,84 foram os preditores de índice de Apgar de 5º min < 7 para recém-nascidos < 29 e ≥ 29 semanas, respectivamente. IR AU e RCP apresentaram acurácia moderada na predição de DPA (área sob a curva ROC de 0,76 e 0,72, respectivamente). Conclusão: IR UA mostrou-se preditor significativo de DPA. RCP revelou-se possível preditora de cesariana por CFI e DPA em recémnascidos prematuros tardios e a termo.

Mild controlled hypothermia for necrotizing enterocolitis treatment to preterm neonates: low technology technique description and safety analysis.

We performed a quality improvement project to necrotizing enterocolitis (NEC) and published our results about the initiative in 2021. However, aspects on the safety of the cooling and how to do therapeutic hypothermia with low technology to preterm infants are not described in this previous reporter. Thus, we aim to describe the steps and management to apply hypothermia in preterm infants using low technology and present the safety aspects regarding the initiative. We performed a quality improvement project to NEC in a reference hospital for neonatology (intensive care unit). Forty-three preterm infants with NEC (modified Bell's stage II/III) were included: 19 in the control group (2015-2018) and 24 in the hypothermic group (2018-2020). The control group received standard treatments. The hypothermia group received standard treatment and underwent passive cooling (35.5 °C, used for 48 h after NEC diagnosis). We reported cooling safety to NEC, assessing hematological and gasometrical parameters, coagulation disorders, clinical instability, and neurological disorders. We described how to perform cooling to preterm infants using incubators' servo-control and the occurrence and management of dysthermia during the cooling. We turn-off the incubator and used the esophageal probe to monitor the temperature every 15 min; if the temperature dropped, the incubator was turned on with a rewarming speed of 0.5 °C/h. The participants' average weights and gestational ages were 1186 g and 32 weeks, respectively. There were no differences among hematological indices, serum parameters (sodium, potassium, creatinine, lactate, and bicarbonate), pH, pCO2, and pO2/FiO2 between the groups during treatment and after rewarming. We did not observe dysthermia, bradycardia, hemodynamic instability, apnea, seizure, bleeding, peri-intraventricular hemorrhage, or any alterations in ventilatory parameters due to the cooling technique in preterm babies. This simple technique was performed without intercurrences through a rigorous team evaluation, with a target cooling speed of 0.5 °C/h. The target temperature was successfully reached between the second and third hours of life with the incubator control in 21 children; ice bags were used in only three cases. The temperature was maintained at the expected level during the programmed cooling period. CONCLUSION: Mild controlled hypothermia for preterm infants with NEC is safe. The cooling of preterm infants could be performed through passive methods, using the servo-control of the incubators for temperature management. WHAT IS KNOWN: • Mild controlled hypothermia to NEC treatment is feasible and associated with a decrease in NEC surgery, short bowel, and death. • Mild controlled hypothermia to preterm is feasible and can be performed through low technology and passive cooling. WHAT IS NEW: • Mild controlled hypothermia to preterm is safe and does not associate with safety adverse effects during and after the cooling. • Preterm infants can be cooled through passive methods by just using the servo control of the incubator, presenting acceptable temperature variance, without dysthermia, achieving and remaining at the target temperature with a proper cooling speed. Mild controlled temperature for preterm infants does not need an additional cooling device.

Low technology, mild controlled hypothermia for necrotizing enterocolitis treatment: an initiative to improve healthcare to preterm neonates.

Necrotizing enterocolitis (NEC) treatment remains unchanged for years. Data suggest that mild controlled hypothermia could potentially improve NEC outcomes. Our units presented unfavourable outcomes on NEC. The aim was to assess our experience with low technology, mild controlled hypothermia on NEC outcomes, and improve preterm infants' healthcare. This was a single-center quality improvement study with retrospective cohort design at the neonatal intensive care unit in the university hospital. Forty-three preterm infants with NEC (Modified Bell's Stage II/III) were included: 19 in the control group (2015-2018) and 24 in the hypothermia group (2018-2020). The control group received standard treatment (fasting, abdominal decompression, and broad-spectrum antibiotics). The hypothermia group underwent cooling to 35.5 °C for 48 h after NEC diagnosis, along with conventional treatment. The primary outcomes are intestinal perforation, need for surgery, duration of parenteral nutrition, death, and extensive resection of the small intestine. There was no statistical difference in the NEC score. The hypothermia group required less surgery (aRR 0.40; 95% CI 0.19-0.85), presented less bowel perforation (aRR 0.39; 95% CI 0.18; 0.83), had a shorter duration of parenteral nutrition (aHR 5.28; 95% CI 1.88-14.89), did not need extensive intestinal resection, (0 vs 15.7%), and did not experience any deaths (0 vs 31.6%).Conclusions: In our experience, low technology, mild controlled hypothermia was feasible, not related to adverse effects, and effective treatment for NEC Modified Bell's Stage II/III. It avoided surgery, bowel perforation, and extensive intestinal resection; reduced mortality; and shortened parenteral nutrition duration. What is Known: • New approaches have been proposed to avoid enterocolitis incidence; however, the treatment of enterocolitis stage 2 has been the same for decades, and unfavourable outcomes remain despite conventional management. • Studies suggest that hypothermia can be an alternative to enterocolitis treatment. What is New: • Mild controlled hypothermia can be an additional practice to treat enterocolitis stage 2, is feasible, and is not related to adverse effects to preterm infants. • It can decrease surgery needs, duration of parenteral nutrition, and death and avoids extensive intestinal resection in preterm infants.

Epidemiological Risk Factors and Perinatal Outcomes of Congenital Anomalies.

Objectives To identify the epidemiological risk factors for congenital anomalies (CAs) and the impact of these fetal malformations on the perinatal outcomes. Methods This prospective cohort study comprised 275 women whose fetuses had CAs. Maternal variables to establish potential risk factors for each group of CA and perinatal outcomes were evaluated. The primary outcome was CA. Secondary outcomes included: fetal growth restriction (FGR); fetal distress (FD); premature rupture of membranes (PROM); oligohydramnios or polyhydramnios; preterm delivery (PTD); stillbirth; cesarean section; low birth weight; Apgar score < 7 at the 1st and 5th minutes; need for assisted ventilation at birth; neonatal infection; need for surgical treatment; early neonatal death; and hospitalization time. Chi-square (χ(2)) test and multilevel regression analysis were applied to compare the groups and determine the effects of maternal characteristics on the incidence of CAs. Results The general prevalence of CAs was of 2.4%. Several maternal characteristics were associated to CAs, such as: age; skin color; level of education; parity; folic acid supplementation; tobacco use; and history of previous miscarriage. There were no significant differences among the CA groups in relation to FGR, FD, PROM, 1-minute Apgar score > 7, and need for assisted ventilation at birth. On the other hand, the prevalence of the other considered outcomes varied significantly among groups. Preterm delivery was significantly more frequent in gastrointestinal tract/abdominal wall defects. The stillbirth rate was increased in all CAs, mainly in isolated fetal hydrops (odds ratio [OR]: 27.13; 95% confidence interval [95%CI]: 2.90-253.47). Hospitalization time was higher for the urinary tract and congenital heart disease groups (p < 0.01). Neonatal death was significantly less frequent in the central nervous system anomalies group. Conclusion It was possible to identify several risk factors for CAs. Adverse perinatal outcomes were presented in all CA groups, and may differ according to the type of CA considered.

Epidemiological Risk Factors and Perinatal Outcomes of Congenital Anomalies / Fatores de risco epidemiológicos e resultados perinatais das anomalias congênitas

Abstract Objectives To identify the epidemiological risk factors for congenital anomalies (CAs) and the impact of these fetal malformations on the perinatal outcomes. Methods This prospective cohort study comprised 275 women whose fetuses had CAs. Maternal variables to establish potential risk factors for each group of CA and perinatal outcomes were evaluated. The primary outcome was CA. Secondary outcomes included: fetal growth restriction (FGR); fetal distress (FD); premature rupture of membranes (PROM); oligohydramnios or polyhydramnios; preterm delivery (PTD); stillbirth; cesarean section; low birth weight; Apgar score < 7 at the 1st and 5th minutes; need for assisted ventilation at birth; neonatal infection; need for surgical treatment; early neonatal death; and hospitalization time. Chi-square (x2) test and multilevel regression analysis were applied to compare the groups and determine the effects of maternal characteristics on the incidence of CAs. Results The general prevalence of CAs was of 2.4%. Several maternal characteristics were associated to CAs, such as: age; skin color; level of education; parity; folic acid supplementation; tobacco use; and history of previous miscarriage. There were no significant differences among the CA groups in relation to FGR, FD, PROM, 1-minute Apgar score > 7, and need for assisted ventilation at birth. On the other hand, the prevalence of the other considered outcomes varied significantly among groups. Preterm delivery was significantly more frequent in gastrointestinal tract/abdominal wall defects. The stillbirth rate was increased in all CAs, mainly in isolated fetal hydrops (odds ratio [OR]: 27.13; 95% confidence interval [95%CI]: 2.90-253.47). Hospitalization time was higher for the urinary tract and congenital heart disease groups (p < 0.01). Neonatal death was significantly less frequent in the central nervous system anomalies group. Conclusion It was possible to identify several risk factors for CAs. Adverse perinatal outcomes were presented in all CA groups, and may differ according to the type of CA considered.

Resumo Objetivos Identificar os fatores epidemiológicos de risco para anomalias congênitas (ACs) e o impacto destas malformações fetais sobre os resultados perinatais. Métodos Este estudo de coorte prospectivo compreendeu 275 mulheres cujos fetos tinham ACs. Variáveis maternas para estabelecer potenciais fatores de risco para cada grupo de AC e resultados perinatais foram avaliados. O desfecho primário foi CAs. Os desfechos secundários incluíram: restrição de crescimento fetal (RCF); sofrimento fetal (SF); ruptura prematura de membranas (RPM); oligo-hidrâmnio ou polidrâmnio; parto pré-termo (PPT); morte fetal; parto cesárea; baixo peso ao nascer; índice de Apgar < 7 no 1° e 5° minutos; necessidade de ventilação assistida no momento do nascimento; infecção neonatal; necessidade de tratamento cirúrgico; óbito neonatal precoce; e tempo de internação. Teste de Qui-quadrado (x2) e análise de regressãomúltipla foram aplicados para comparar os resultados entre os grupos e determinar os efeitos das características maternas sobre a incidência de ACs. Resultados A prevalência geral de ACs foi de 2.4%. Várias características maternas foram associadas às ACs, tais como: idade; cor da pele; escolaridade; paridade; suplementação com ácido fólico; tabagismo; e histórico de aborto anterior. Não houve diferenças significativas entre os grupos de ACs com relação à RCF, SF, RPM, índice de Apgar < 7 no 1°minuto e necessidade de ventilação assistida no nascimento. Por outro lado, a prevalência dos demais resultados adversos considerados variou significativamente entre os grupos. O parto pré-termo foi significativamente mais frequente nos casos de defeitos do trato gastrointestinal/parede abdominal. As taxas de óbito fetal foram elevadas em todos os grupos de ACs, principalmente na hidropsia fetal isolada (odds ratio [OR]: 27.13; intervalo de confiança de 95% [IC95%]: 2.90-253.47). O tempo de internação foi maior nos casos de anomalias do trato urinário e nas cardiopatias congênitas (p < 0,01). O óbito neonatal foi significativamente menos frequente no grupo de anomalias do sistema nervoso central. Conclusão Foi possível identificar vários fatores de risco para ACs. Resultados perinatais adversos foram observados em todos os grupos de ACs, e podem diferir de acordo com o tipo de AC considerada.

[Fetal cardiac rhabdomyoma: analysis of five cases]. / Rabdomiomas cardíacos fetais: análise de cinco casos.

PURPOSE: to analyze the differential diagnosis, follow-up and therapeutic approach in five cases of primary cardiac tumors diagnosed during the prenatal period. METHODS: during the period from January 1997 to December 2008, 7989 pregnant women were submitted to morphological ultrasound due to the presence of risk factors for fetal malformations. Fetuses with hyperechogenic intracardiac masses larger than 1 mm diagnosed by ultrasound evaluation of the fetal heart, were selected for study. The differential diagnosis between the different tumor types was made on the basis of the ultrasound characteristics of the masses. RESULTS: five fetuses with hiperechogenic intracardiac masses were diagnosed, corresponding to a 0.06% prevalence rate. Gestational age ranged from 28 to 36 weeks (mean: 31), and maternal age ranged from 23 to 45 years (mean: 34.2). The most frequent location of the masses was the left ventricle (100%). Echographically, all masses were single or multiple, hyperechogenic, homogeneous and well delimited, compatible with a diagnosis of rhabomyoma. In cases in which the diameters of the masses were less than 20 mm, an expectant conduct was followed and no complications occurred during the prenatal period. One case with a huge tumor presented arrhythmia and cardiac insufficiency during the 35 gestational weeks, and the interruption of pregnancy was indicated. Tuberous sclerosis was associated in four cases (80%) and the diagnosis was confirmed during the postnatal follow-up. CONCLUSIONS: fetal morphological ultrasonography is the main form of early detection of primary cardiac tumors. The fetal cardiac evaluation is of fundamental importance for the differential morphological characterization of cardiac masses and for the evaluation of cardiac function. Rhabdomyomas are the most common type of fetal tumor. An expectant pre and postnatal conduct is followed, with a low risk of complications and with the possibility of spontaneous regression in most cases. Postnatal clinical follow-up is mandatory due to the high frequency of associated tuberous sclerosis.

Rabdomiomas cardíacos fetais: análise de cinco casos / Fetal cardiac rhabdomyoma: analysis of five cases

OBJETIVO: analisar o diagnóstico, evolução e conduta terapêutica em cinco casos de tumores cardíacos primários diagnosticados no período pré-natal. MÉTODOS: no período de Janeiro 1997 a Dezembro 2008, 7.989 gestantes foram submetidas à avaliação ultrassonográfica morfológica fetal devido à presença de fatores de risco para malformações fetais. Foram selecionados os casos com massas hipercogênicas intracardíaca maiores que 1 mm diagnosticados na avaliação ultrassonográfica do coração fetal. O diagnóstico diferencial dos tumores foi realizado segundo as características ultrassonográficas das massas. RESULTADOS: em cinco fetos foram diagnosticadas massas hiperecogênicas intracardíaca correspondendo a uma taxa de prevalência de 0,06 por cento. A idade gestacional variou entre a 28ª e a 36ª semanas (média=31) e a idade materna variou de 23 a 45 anos (média=34,2). A localização mais frequente das massas foi o ventrículo esquerdo (100 por cento). Ecograficamente, todas as massas eram hipercogênicas, homogêneas, únicas ou múltiplas e bem delimitadas, compatíveis com diagnóstico de um rabdomioma. Nos casos em que os diâmetros das massas foram menores que 20 mm, a conduta foi expectante e não houve complicações no período pré-natal. Um caso com tumor de grande volume apresentou arritmia e insuficiência cardíaca na 35ª semana de gestação, sendo indicada a interrupção da gestação. Em 80 por cento dos casos foi observada associação com esclerose tuberosa no seguimento pós-natal. A regressão dos tumores cardíacos ocorreu em três casos (60 por cento) durante um seguimento médio de três anos. Todos os recém-nascidos eram do sexo masculino e sem antecedentes familiares de esclerose tuberosa. CONCLUSÕES: a avaliação ultrassonográfica morfológica fetal é a principal forma de detecção precoce dos tumores cardíacos primários. A avaliação cardíaca fetal é fundamental para a caracterização morfológica diferencial das massas cardíacas e para avaliação funcional cardíaca...

PURPOSE: to analyze the differential diagnosis, follow-up and therapeutic approach in five cases of primary cardiac tumors diagnosed during the prenatal period. METHODS: during the period from January 1997 to December 2008, 7989 pregnant women were submitted to morphological ultrasound due to the presence of risk factors for fetal malformations. Fetuses with hyperechogenic intracardiac masses larger than 1 mm diagnosed by ultrasound evaluation of the fetal heart, were selected for study. The differential diagnosis between the different tumor types was made on the basis of the ultrasound characteristics of the masses. RESULTS: five fetuses with hiperechogenic intracardiac masses were diagnosed, corresponding to a 0.06 percent prevalence rate. Gestational age ranged from 28 to 36 weeks (mean: 31), and maternal age ranged from 23 to 45 years (mean: 34,2). The most frequent location of the masses was the left ventricle (100 percent). Echographically, all masses were single or multiple, hyperechogenic, homogeneous and well delimited, compatible with a diagnosis of rhabomyoma. In cases in which the diameters of the masses were less than 20 mm, an expectant conduct was followed and no complications occurred during the prenatal period. One case with a huge tumor presented arrhythmia and cardiac insufficiency during the 35 gestational weeks, and the interruption of pregnancy was indicated. Tuberous sclerosis was associated in four cases (80 percent) and the diagnosis was confirmed during the postnatal follow-up. CONCLUSIONS: fetal morphological ultrasonography is the main form of early detection of primary cardiac tumors. The fetal cardiac evaluation is of fundamental importance for the differential morphological characterization of cardiac masses and for the evaluation of cardiac function. Rhabdomyomas are the most common type of fetal tumor. An expectant pre and postnatal conduct is followed, with a low risk of complications and with the possibility of spontaneous...

Effect of fortification of drinking water with iron plus ascorbic acid or with ascorbic acid alone on hemoglobin values and anthropometric indicators in preschool children in day-care centers in Southeast Brazil.

BACKGROUND: Iron-deficiency anemia currently is the most frequently occurring nutritional disorder world-wide. Previous Brazilian studies have demonstrated that drinking water fortified with iron and ascorbic acid is an adequate vehicle for improving the iron supply for children frequenting day-care centers. OBJECTIVE: The objective of this study was to clarify the role of ascorbic acid as a vehicle for improving iron intake in children in day-care centers in Brazil. METHODS: A six-month study was conducted on 150 children frequenting six day-care centers divided into two groups of three day-care centers by drawing lots: the iron-C group (3 day-care centers, n = 74), which used water fortified with 10 mg elemental iron and 100 mg ascorbic acid per liter, and the comparison group (3 day-care centers, n = 76), which used water containing only 100 mg ascorbic acid per liter. Anthropometric measurements and determinations of capillary hemoglobin were performed at the beginning of the study and after six months of intervention. The food offered at the day-care centers was also analyzed. RESULTS: The food offered at the day-care center was found to be deficient in ascorbic acid, poor in heme iron, and adequate in non-heme iron. Supplementation with fortified drinking water resulted in a decrease in the prevalence of anemia and an increase in mean hemoglobin levels associated with height gain in both groups. CONCLUSIONS: Fortification of drinking water with iron has previously demonstrated effectiveness in increasing iron supplies. This simple strategy was confirmed in the present study. The present study also demonstrated that for populations receiving an abundant supply of non-heme iron, it is possible to control anemia in a simple, safe, and inexpensive manner by adding ascorbic acid to drinking water.

Transição nutricional em crianças de Ribeirão Preto, SP, Brasil / Nutritional transition in children of Ribeirão Preto, Brazil

Objetivo: avaliar o estado nutricional de um grupo de crianças pré-escolares da cidade de Ribeirão Preto, interior do Estado de São Paulo. Métodos: foram avaliadas, por meio de método antropométrico, 2.063 crianças com idades entre 6 e 96 meses, provenientes das cinco regiões em que se subdivide a cidade, obtendo-se os escores z dos indicadores peso para idade, peso para estatura e estatura para idade. Resultados: as prevalências de baixo peso para idade (2,8 por cento), baixo peso para esatura (1,9 por cento) e baixa estatura para idade (3,2 por cento) foram em geral baixas, contrastando com a maior prevalência de obesidade (6,7 por cento). A distribuição, quanto ao esatdo nutricional, foi diferente entre as regiões, sendo que na região leste foi observada alta prevalência (4,1 por cento) de crianças com indicador sugestivo de subnutrição aguda. Na região oeste, predominaram os acsos de nanismo nutricional (4,9 por cento). A prevalência de obesidade foi alta nas regiões centro-sul (9,5 por cento), norte (7,4 por cento) e leste (7,1 por cento) e menor na região oeste (3,9 por cento). Conclusão: a cidade de Ribeirão Preto está atravessando o processo de transição nutricional em que se podem encontrar, coexistindo, casos de subnutrição de caráter agudo e pregresso com casos de obesidade. Essta transição foi observada de forma diferente dentre as regiões estudadas, com tendência a apresentação de indicadores semelhantes aos dos países desenvolvidos, nas regiões mais ricas, em especial a centro-sul, e indicadores semelhantes aos de países em desenvolvimento, nas regiões mais carentes.

Monte Alto sem anemia, primeira fase: avaliação nutricional das crianças pré-escolares / The city of Monte Alto: nutritional status in preschool children

Objetivos: Com a finalidade de preparar um programa municipal de intervenção nutricional, foi realizado levantamento das condições nutricionais das crianças intitucionalizadas nas 9 creches da cidade de Monte Alto, SP. Métodos: Em estudo transversal, foram avaliadas 503 crianças com idades entre 12 e 83,9 meses, no período entre 1º e 31 de agosto de 2002. De cada criança foram obtidos dados pessoais, peso, estatura e colhida amostra de sangue para dosagem de hemoglobina capilar. Resultados: A prevalência global de anemia foi de 14,5 por cento e a média de hemoglobina de 11,8 g/dl. As prevalências de déficit (escore z < -2) para os indicadores peso para idade, estatura para idade e peso para estatura foram de respectivamente 2,6 por cento, 1,6 por cento e 4 por cento. A prevalência de obesidade (escore z de peso para estatura > 2) foi de 4,2 por cento. Conclusões: Observaram-se prevalências relativamente baixas entre os distúrbios nutricionais estudados, sendo que a anemia se evidenciou o mais relevante. A obesidade mostrou-se discretamente mais prevalente que a subnutrição, indicando o provável início de um processo de transição nutricional.

Prevalência de tabagismo no domicilio de escolares de Ribeirão Preto, SP / Smoking prevalence at school children home in Ribeirão Preto, SP, Brazil

Objetivo : conhecer a prevalencia de fumantes passivos, na faixa etaria escolar. Casuistica e metodos : foi realizado um estudo epidemiologico transversal para avaliar...

Ducto venoso: da anatomia à avaliaçäo do bem-estar fetal / Ductus venosus: from the anatomy to fetal well being evaluation

O ducto venoso é a continuaçäo da veia umbilical com a veia cava inferior, e ele, posteriormente ao nascimento, oblitera-se, formando o ligamento venoso. Por meio dele, o sangue rico em oxigênio, proveniente da veia umbilical, chega ao átrio direito e a partir daí, pelo forame oval, ganha o átrio esquerdo e a circulaçäo sistêmica, favorecendo o fluxo para órgäos vitais como o cérebro fetal. Em obstetrícia, a ultra-sonografia Doppler tem sido amplamente utilizada para se examinar o sistema arterial fetal. Recentemente, mais atençäo tem sido dispensada ao sistema venoso. O estudo das ondas de velocidade de fluxo venoso pode desempenhar um papel importante na avaliaçäo do bem-estar fetal, uma vez que a velocimetria do ducto venoso pode estar alterada na vigência de patologias fetais. A característica mais interessante é a reduçäo ou fluxo reverso durante a contraçäo atrial, comumente encontrada em fetos com defeitos cardíacos congênitos, arritmias, transfusäo fetofetal grave e restriçäo de crescimento intra-útero. Este texto tem a finalidade de revisar as características anatômicas e funcionais do ducto venoso fetal, bem como a importância de sua avaliaçäo ultra-sonográfica pré-natal