Fatores de risco para asfixia neonatal em recém-nascidos com peso acima de 1000 gramas

Abstract

Objective

To evaluate some of the risk factors for neonatal asphyxia in neonates weighing more than 1000 grams. Methods: Out of a population of 13,385 consecutive deliveries from January 1991 to December 1994, we compared 135 newborns with neonatal asphyxia with 135 newborns without the disease, in a case-control study matched by birth weight at the Neonatology Unit of the Pediatric Department at the Universidade Estadual de Campinas (Unicamp), Brazil. The statistical analysis was bivariate and multiple by logistic regression, and expressed as odds ratio (OR) with 95% confidence intervals. Results: In the bivariate analysis, the factors significantly associated with asphyxia were: abruptio placentae (OR = 8.00 [1.07-353.4]), cesarean delivery (OR = 2.94 [1.64-5.55]), breech presentation (OR= 3.33 [1.54-7.98]), abnormal fetal heart rates (OR= 4.88 [2.25-12.08]), prolonged rupture of membranes (OR= 4.33 [1.19-23.71]), meconial hemorrhagic or infected amniotic fluid (OR= 9.00 [3.58-29.03]), oligohydramnios or polyhydramnios (OR=5.00 [1.88-16.76]), use of anesthesia (OR= 2.56 [1.41-4.89]) and general anesthesia (OR = 14.00 [2.13-598.8]), male sex (OR= 2.06 [1.12-3.92]) and gestational age of less than 37 weeks (OR= 3.29 [1.37-9.07]). After multiple analysis, abnormal amniotic fluid, oligohydramnios or polyhydramnios, and anesthesia were the only factors associated with neonatal asphyxia, and more than six prenatal visits was a protecting factor. Conclusions: Obstetrical, perinatal and neonatal clinical events are associated with neonatal asphyxia. Concerted efforts to provide adequate prenatal care, optimal assistance during labor and delivery, and appropriate neonatal intensive care should significantly reduce neonatal morbidity and mortality.

Methods

Out of a population of 13,385 consecutive deliveries from January 1991 to December 1994, we compared 135 newborns with neonatal asphyxia with 135 newborns without the disease, in a case-control study matched by birth weight at the Neonatology Unit of the Pediatric Department at the Universidade Estadual de Campinas (Unicamp), Brazil. The statistical analysis was bivariate and multiple by logistic regression, and expressed as odds ratio (OR) with 95% confidence intervals. Results: In the bivariate analysis, the factors significantly associated with asphyxia were: abruptio placentae (OR = 8.00 [1.07-353.4]), cesarean delivery (OR = 2.94 [1.64-5.55]), breech presentation (OR= 3.33 [1.54-7.98]), abnormal fetal heart rates (OR= 4.88 [2.25-12.08]), prolonged rupture of membranes (OR= 4.33 [1.19-23.71]), meconial hemorrhagic or infected amniotic fluid (OR= 9.00 [3.58-29.03]), oligohydramnios or polyhydramnios (OR=5.00 [1.88-16.76]), use of anesthesia (OR= 2.56 [1.41-4.89]) and general anesthesia (OR = 14.00 [2.13-598.8]), male sex (OR= 2.06 [1.12-3.92]) and gestational age of less than 37 weeks (OR= 3.29 [1.37-9.07]). After multiple analysis, abnormal amniotic fluid, oligohydramnios or polyhydramnios, and anesthesia were the only factors associated with neonatal asphyxia, and more than six prenatal visits was a protecting factor. Conclusions: Obstetrical, perinatal and neonatal clinical events are associated with neonatal asphyxia. Concerted efforts to provide adequate prenatal care, optimal assistance during labor and delivery, and appropriate neonatal intensive care should significantly reduce neonatal morbidity and mortality.

Results

In the bivariate analysis, the factors significantly associated with asphyxia were: abruptio placentae (OR = 8.00 [1.07-353.4]), cesarean delivery (OR = 2.94 [1.64-5.55]), breech presentation (OR= 3.33 [1.54-7.98]), abnormal fetal heart rates (OR= 4.88 [2.25-12.08]), prolonged rupture of membranes (OR= 4.33 [1.19-23.71]), meconial hemorrhagic or infected amniotic fluid (OR= 9.00 [3.58-29.03]), oligohydramnios or polyhydramnios (OR=5.00 [1.88-16.76]), use of anesthesia (OR= 2.56 [1.41-4.89]) and general anesthesia (OR = 14.00 [2.13-598.8]), male sex (OR= 2.06 [1.12-3.92]) and gestational age of less than 37 weeks (OR= 3.29 [1.37-9.07]). After multiple analysis, abnormal amniotic fluid, oligohydramnios or polyhydramnios, and anesthesia were the only factors associated with neonatal asphyxia, and more than six prenatal visits was a protecting factor. Conclusions: Obstetrical, perinatal and neonatal clinical events are associated with neonatal asphyxia. Concerted efforts to provide adequate prenatal care, optimal assistance during labor and delivery, and appropriate neonatal intensive care should significantly reduce neonatal morbidity and mortality.

Conclusions

Obstetrical, perinatal and neonatal clinical events are associated with neonatal asphyxia. Concerted efforts to provide adequate prenatal care, optimal assistance during labor and delivery, and appropriate neonatal intensive care should significantly reduce neonatal morbidity and mortality.

Resumen

Objetivo

Avaliar alguns fatores de risco para asfixia neonatal em recém-nascidos vivos com peso acima de 1000 gramas.

Métodos

De uma população de 13.385 partos consecutivos, no período de janeiro de 1991 a dezembro de 1994, foram comparados 135 recém-nascidos com asfixia neonatal e 135 sem a doença, num estudo caso-controle emparelhado pelo peso, no Serviço de Neonatologia do Departamento de Pediatria da Unicamp. A análise estatística foi bivariada e múltipla por regressão logística, calculando-se a razão de chance (O.R.) com intervalo de confiança de 95%.

Resultados

Na análise bivariada, as variáveis associadas com a asfixia foram descolamento prematuro de placenta [O.R.= 8.00 (1,07- 353,4)], parto cesárea [O.R.= 2,94 (1,64 - 5,55)], apresentação pélvica [O.R.= 3,33 (1,54 - 7,98)], sofrimento fetal [O.R.= 4,88 (2,25 - 12,08)], rotura prolongada de membranas [O.R.= 4,33 (1,19 - 23,71)], líquido amniótico meconial, hemorrágico ou purulento [O.R.= 9,00 (3,58 - 29,03)], oligoâmnio ou poliidrâmnio [O.R.=5,00 (1,88 - 16,76), uso de anestesia [O.R.= 2,56 (1,41 - 4,89)] e anestesia geral [O.R. = 14,00 (2,13 - 598,8)], sexo masculino O.R.= 2,06 (1,12 - 3,92)] e idade gestacional abaixo de 37 semanas [O.R.= 3,29 (1,37 - 9,07). Após a análise múltipla, o líquido amniótico não claro, a anestesia, o oligoâmnio ou poliidrâmnio permaneceram como fatores de risco independentes para asfixia, enquanto o número de consultas de pré-natal maior que seis apareceu como fator protetor.

Conclusões

A asfixia neonatal associa-se a eventos clínicos obstétricos, perinatais e neonatais; assim combinar esforços para prover cuidado pré-natal adequado, ótima atenção ao parto e nascimento e cuidado intensivo neonatal poderia reduzir significativamente a morbidade e mortalidade neonatal pela doença.