Surfactant replacement therapy in neonates with respiratory distress syndrome

Abstract

Objective To study the efficacy and clinical value of pulmonary surfactant (PS) replacement therapy in newborn infants with respiratory distress syndrome (NRDS) . Method The study was a prospective controlled clinical trial. Twenty-five neonates with NRDS were treated with single dose pulmonary surfactant by intratracheal administration and an other twenty-five newborn infants with NRDS who received no surfactant replacement therapy were enrolled as control group between April 1996 and August 1998. Results Hypoxemia in the patients of PS-treated group was maricedly relieved within 2 to 3 hours after administration of surfactant, values for arterial partial pressure of oxygen ( PaO2) , arterial oxygen/alveolar oxygen ratio (a/A P02) and ventilator efficiency index (VEI) significantly increased from (48 ± 14) mm Hg ( 1 mm Hg = 0.133 kPa) , 0.14 ± 0.06 and (0.16±0.09) ml/ (mm Hg·kg) to (65 ± 29) mm Hg, 0.24± 0.15 and (0.29 ± 0.16) ml/ (mm Hg·kg) , but oxygenation index (OI) , fraction of inspired oxygen (FiO2) , and mean airway pressure (MAP) decreased gradually from 11.6 ± 5.7, 0.59 ± 0.13 and (15.6 ± 3.1) cm H2O (1 cm H2O = 0.098 kPa) to (6.3±3.4) , 0.47 ± 0.10and (13.5 ± 2.4) cm H2O after 6 hours of administration. Main effects, group and treatment time had marked effects on values of PaO2, a/A PO2, OI、FiO2, MAP and VEI in the two groups, but 2-way interactions between group and treatment time had no effect on them by analysis of general linear model and LSD test. Duration of assisted ventilation and supplemental oxygen administration in PS-treated group was significantly shortened as compared to control group. Conclusion The results indicate that surfactant replacement therapy may result in a rapid improvement in dynamic compliance and oxygenation, and decrease duration of assisted ventilation and supplemental oxygen administration in the newborns with NRDS. Key words: Pulmonary surfactants; Infant, newborn; Respiratory distress syndrome