Impact of respiratory distress syndrome in very low birth weight infants: a multicenter South-American study

Objective. To analyze the incidence, risk factors, major morbidity, mortality and resource employment in very low birth weight infants (< 1500 g) with respiratory distress syndrome (RDS). Methods. Descriptive study using prospectively obtained on-line information from a data base of 20 units belonging to the South American Neocosur Network. A total of 5991 VLBW infants were registered during years 2002-2007. Results. The mean gestacional age was 29.1 weeks (95% CI 29.06-29.21) and the mean of birth weight was 1100.5 g (95% CI 1093.79-1107.37). The global incidence of RDS was 74% (95% CI 73-75). Antenatal steroids were administered to 73% of this population. The main risk factor was lower gestational age (p< 0.001); where as prenatal steroids (OR: 0.59; 95% CI 0.49-0.72), female gender (OR: 0.77; 95% CI 0.67-0.89) and premature rupture of membranes (OR: 0.81; 95% CI 0.68-0.96) were protective factors. Antenatal steroids was also associated with a decrease in mortality in those infants that presented with RDS (OR: 0.40; 95% CI 0.34-0.47). Use of resources was higher in the group with RDS, with a greater use of surfactant (74.3% vs. 7.3%, p< 0.001), mechanical ventilation (82.1% vs. 23.8%, p< 0.001), and more days of oxygen (median of 8 vs. 1 day, p< 0.001) and hospitalization (median of 61 vs. 45 days, p< 0.001). RDS was associated to an increase risk in the incidence of ROP, PDA, late onset sepsis, severe IVH and oxygen requirement at 36 weeks of corrected gestational age. Conclusions. RDS had a high incidence in very low birth weight infants, despite the frequent use of antenatal steroids. VLBW Infants with RDS had a higher mortality and an increase risk of relevant morbidity. RDS also increased use of resources.