Revista Brasileira de Ginecologia e Obstetrícia (Jul 2010)
Fatores preditores para o óbito neonatal em gestações com diástole zero ou reversa na doplervelocimetria da artéria umbilical Predictor parameters of neonatal death in gestations with absent or reverse end-diastolic flow in the umbilical artery doppler velocimetry
Abstract
OBJETIVO: avaliar os fatores de risco antenatais e pós-natais para o óbito neonatal em gestações com diástole zero (DZ) ou reversa (DR) na doplervelocimetria da artéria umbilical. MÉTODOS: estudo transversal, retrospectivo, inferencial, a partir de 48 prontuários de gestações únicas com DZ ou DR, idade gestacional entre 24 e 34 semanas, em uma maternidade no Nordeste do Brasil. A média de idade foi de 27,3 anos (DP: 7,9). Vinte (41,7%) eram primigestas. Síndromes hipertensivas foram observadas em 44 (91,7%) casos. Trinta e cinco (72,9%) apresentavam DZ e 13 (27,1%) DR. Procedeu-se inicialmente à análise univariada (teste t de Student e teste Exato de Fisher), relacionando os parâmetros com o desfecho avaliado (óbito neonatal). As variáveis que apresentaram associação significativa foram incluídas no modelo de regressão logística (Estatística de Wald). O nível de significância utilizado foi de 5%. RESULTADOS: a mortalidade perinatal foi de 64,6% (31/48). Ocorreram cinco óbitos fetais e 26 neonatais. A média de idade gestacional no momento do diagnóstico foi de 27,9 (DP: 2,8) semanas. A resolução da gestação antes de 24 horas após o diagnóstico ocorreu em 52,1% dos casos. Parto abdominal foi realizado em 85,4% dos casos. Os recém-nascidos pesaram em média 975,9 g (DP: 457,5). Vinte e quatro (57,1%) apresentaram Apgar menor que 7 no primeiro minuto e 21,4%, no quinto. A idade gestacional no momento do diagnóstico, o peso ao nascer e o Apgar de primeiro minuto revelaram-se variáveis significativamente relacionadas com o óbito neonatal (valores de p foram, respectivamente, 0,008; 0,004 e 0,020). As razões de chance foi de 6,6; 25,3 e 13,8 para o óbito neonatal, quando o diagnóstico foi estabelecido até a 28ª semana, peso PURPOSE: to evaluate the antenatal and postnatal risk factors of neonatal death in pregnancies with absent (DZ) or reverse (DR) end-diastolic flow in the umbilical artery. METHODS: a cross-sectional retrospective study based on data from 48 medical records of singleton pregnancies with DZ or DR, and gestational age of 24 to 34 weeks, at a maternity in the Brazilian Northeast. Mean age was 27.3 (SD: 7.9) years. Twenty (41.7%) patients were primiparas. Hypertensive disorders were found in 44 (91.7%) cases. Thirty-five women (72.9%) had DZ and 13 (27.1%) had DR. Univariate analysis was firstly done (Student's t-test and Fisher's exact test) correlating the parameters with the assessed outcome (neonatal death). Variables that showed significant association were included in the logistic regression model (Wald statistics). The level of significance was set at 5%. RESULTS: The perinatal mortality rate was 64.6% (31/48). There were five stillbirths and 26 neonatal deaths. The mean gestational age at diagnosis was 27.9 (SD: 2.8) weeks. Deliveries before 24 hours after diagnosis occurred in 52.1% of the cases. Cesarean section was performed in 85.4% of the sample. The newborns weighed 975.9 g on average (SD: 457.5). Twenty-four (57.1%) presented Apgar scores below 7 in the first minute and 21.4% in the fifth minute. Gestational age at diagnosis, birth weight and Apgar of the first minute proved to be variables significantly related to neonatal death (p values were: 0.008, 0.004, and 0.020, respectively). The Odds Ratio was 6.6, 25.3 and 13.8 for neonatal death, when the diagnosis was established at the 28th week, weight was <1000 g and first minute Apgar score was <7, respectively. CONCLUSIONS: gestational age at diagnosis, birth weight and Apgar score at the first minute were factors that could predict neonatal death in pregnancies with DV or DR determined by umbilical artery Doppler velocimetry.
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