Abstract 1416

CLD has multifactorial etiology, representing a clinic and public health challenge for neonatologists. This complication has been classically associated with pulmonary immaturity, volutrauma (mechanical ventilation), oxygen toxicity and, more recently, with inflammatory factors such as intrauterine infections, postnatal acquired infections excessive fluid intake and patent ductus arteriosus(PDA). Over a three year period (surfactant used with selective criteria), we reviewed and described clinical associations in order to obtain early risk factors for the development of CLD using two criterias: oxygen dependence at 28 days postnatal age and oxygen dependence at 36 week's postconceptional age. This study was performed in a tertiary center (Hospital Dr. Sótero del Río) between 1994-1996. From a Total of 42,302 inborn infants, 444 were VLBW (1.04%). 342 surviving.

Results: We tested risk factors by univariate analysis; no differences in sex distribution or antenatal steroids administration(62%/52%) were observed using both criterias. If criteria oxygen dependence at 28 days was used as criteria, gestational age(GA), birth weight(BW), intraamniotic infection(II), mechanical ventilation(MV), connatal infection(CI), PDA and postnatal infection were significant predictors By using oxygen dependence at 36 week's, risk factors were reduced to BW, MV, connatal infections, PDA, and postnatal infection. Then, data were analyzed by backward stepwise logistic regression.

Conclusion: 1.-Clinical events like GA, intramniotic infection, connatal infection, surfactant needs, MV, and postnatal infection are associated with oxygen dependence at 28 days. 2.-Clinical events like GA, connatal infection MV and PDA are associated with oxygen dependence at 36 week's PCA. Speculation: Connatal and postnatal infection are strongly associated with CLD in VLBW under 29 weeks of gestation. This group may be active treated by obstetricians and neonatologists.