Research on different dose of pulmonary surfactant for the treatment of neonatal respiratory distress syndrome / 中华实用儿科临床杂志

ABSTRACT

Objective To evaluate the relative efficacy of different dosages of Calf Pulmonary Surfactant (Calsurf) administration in premature infants with established respiratory distress syndrome (NRDS).Methods Four neonatal intensive care units in Jiangsu province were enrolled.Premature infants,birth weight ＜ 2 500 g,with NRDS,received 70 mg/kg (61 cases)or 100 mg/kg (69 cases)Calsurf.Clinical and respiratory parameters were recorded.The primary outcome measures were blood gas analysis of 1 h,12 h and 36 h after administration,the need for oxygenation and ventilatory requirements and the adverse events of NRDS.Results Arterial oxygen tension[pa (O2)] results in a significant improvement(80.27-±36.81) mmHg,(73.03 ±24.94) mmHg and (72.35 ± 24.72) mmHg at 1 h,12 h and 24 h in higher dose group(P ＜ 0.05),(67.95 ± 23.79) mmHg,(72.35 ± 24.72) mmHg in 24 h,as compared with the lower dose group at the same time [(67.07 ± 19.94) mmHg,(62.93 ± 21.71) mmHg,(67.95 ±-23.79) mmHg] (P ＞ 0.05).Inspired oxygen (FiO2) and pa (O2) decreased after administration in two groups and the duration of FiO2 decline lasted to 48 h (all P ＜ 0.05).The oxygen index (OI) was improved after Calsurf administration,especially in the infants who received 100 mg/kg of Calsurf with 6.1 ± 2.8,5.6 ± 3.3,5.5 ± 3.5,5.8 ± 4.5,5.3 ± 3.1 in 1 h,12 h,24 h,36 h,48 h,respectively(P ＜ 0.01).The arterial-to-alveolar oxygen tension ratio (a/APO2) of 100 mg/kg group was reduced significantly in 1 h,12 h,24 h,36 h,48 h with 0.39 ±0.22,0.42 ±0.20,0.45 ± 0.22,0.44 ± 0.22,0.46 ± 0.21 as compared with 0.27 ± 0.18 which was at the time point before administration (P ＜ 0.01).Although not statistically significant,the mean time of duration of mechanical ventilation and oxygen inhalation of higher dose group were decreased as compared to the lower dose group [(94.54 ± 113.44) h vs (109.27 ± 124.87) h (P＞0.05) and (259.10 ±280.45) vs (372.31 ±398.08) h(P ＞0.05)].There were no significant differences in the rates of other adverse events such as pneumonia,pneumothorax,intracranial hemorrhage,patent ductus arteriosus (PDA),pneumorrhagia,necrotizing enterocolitis,septicemia between two groups (P ＞ 0.05).Conclusions Calsurf given to preterm infants with NRDS at a dose of 100 mg/kg resulted in a higher Pa (O2),a/APO2,better OI and lower FiO2 as compared with those receiving 70 mg/kg.The need for mechanical ventilation and oxygen supplement were reduced with higher-dose administration.Large dose of Calsurf did not increase the risk of complications as mentioned above.