Risk Factors Contributing to the Failure of Surfactant Administration with INSURE Method
BACKGROUND: The INSURE method (INtubation- SURfactant- Extubation) is effective in decreasing the need for mechanical ventilation and reducing ventilation-related adverse events. The aim of this study was to determine the risk factors for failure of the INSURE method.
METHODS: A prospective descriptive analytical study was conducted in a tertiary level neonatal intensive care unit (NICU) between March 2012 and December 2012. All preterm neonates who received intratracheal surfactant were enrolled in this study and allocated to INSURE failure and INSURE success groups depending on whether they needed intubation and mechanical ventilation or not.
RESULTS: Of the 147 neonates, 45 (30.6%) required intubation within the first 72 hours of intratracheal surfactant administration and, therefore, were included in the failure group. The mean birth weight and gestational age in the failure group were 1342±545 grams and 28.7±2.9 week, respectively, and were significantly lower than the success group (1688±472 grams and 31±2.2 week, respectively; p<0.001). The Apgar scores at 1 and 5 minutes were significantly lower in the failure group than the success group (5.7±2.1 and 7.5±1.3 vs. 7.6±1.5 and 8.8±1, respectively; p<0.001). Respiratory distress syndrome (RDS) score was 8.8±1 in the failure group and 7.1±1.3 in the success group (p<0.001). The need for repeated doses of surfactant in the failure group was more than the success group (odds ratio (OR)=8.24, 95% confidence interval (CI): 3.10- 21.86). The patent ductus arteriosus (OR=3.42, 95% CI: 1.46-8.01; p=0.003) and intra ventricular hemorrhage (OR=4.56, 95% CI: 1.90-10.93; p<0.001) were significantly more common in the failure group.
CONCLUSION: Preterm infants with lower birth weight and gestational age and higher RDS score are at higher risk of INSURE method failure.