[Preterm premature rupture of the fetal membranes: factors associated with bronchopulmonary dysplasia].

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.