Oxygenation index as a respiratory parameter of respiratory distress syndrome in preterm infants

Purpose : To examine whether changes of oxygenation index (OI) by postnatal age were different by the number of surfactant administration, and different between subgroups of survival and death. Methods : From January 2005 to June 2006, preterm infants (n=84) diagnosed as respiratory distress syndrome (RDS) and treated with surfactant and ventilator were included. They were divided into two groups: Group I (n=54) was infants received surfactant, one time and Group II (n=30) was infants received surfactant, two times. We also categorized group I & II infants into two subgroups in each group: survival group and death group. We calculated OI at birth, 24 hr, 48 hr and 72 hr after birth. Results : Gestational age (30.1±2.6 wk vs 28.4±3.4 wk) and birth weight (1,478±442 g vs 1,199±495 g) were different between group I and group II. In preterm infants with RDS, the changes of OI by postnatal age were different between groups (P=0.001) and different with time change (P