Purpose: to analyze obstetric and neonatal factors associated with bronchopulmonary dysplasia outcome in patients with preterm premature amniorrhexis.
Methods: we analyzed 213 medical records of patients of Fernandes Figueira Institute who suffered premature amniorrhexis (<34 weeks of gestation) in the period from 1998 to 2002. Multiple gestations were excluded. Clinical-obstetric and neonatal variables were considered in relation to the bronchopulmonary dysplasia outcome. Data were subjected to bivariate analysis, and the values showing statistical significance (p<0.05) were subjected to logistic regression analysis.
Results: the prevalence of bronchopulmonary dysplasia was 6.10%. Univariate analysis of the factors associated with the pulmonary dysplasia outcome were: neonatal mechanical ventilation for more than ten days(OR: 54.00 [11.55-278.25] p=0.000); birth gestational age of less than 30 weeks (OR: 6.33 [1.26- 43.06] p=0.017); birth weight <1,000 g (OR: 4.82 [1.34-17.53] p=0.010); birth weight <1.500 g (OR: 14.09 [1.82-300.50] p=0.003; patent ductus arteriosus (OR: 12.33 [3.07-50.10], p=0.000); hyaline membrane disease (OR: 8.46 [2.21-35.00] p=0.000); congenital pneumonia (OR: 7.48 [2.03-27.93] p=0.000); use of neonatal surfactant (OR: 19.66 [4.54-97.76] p=0.000), and neonatal infection (OR: 7.67 [0.99-163.79] p=0.049). In the final multivariate model, only the variables "neonatal mechanical ventilation">10 days (p=0.001) and "use of a surfactant" (p=0.040) remained independently associated with bronchopulmonary dysplasia.
Conclusions: the factors associated with bronchopulmonary dysplasia are related to neonatal features, as prolonged mechanical ventilation and the use of a surfactant influence the development of the disease.