Objective    To study the effect of bovine pulmonary surfactant (Calsurf) on cerebral hemodynamics in premature neonates with respiratory distress syndrome (RDS).     Methods    Three hundred and one neonates with RDS admitted to Children’s Hospital of Chongqing Medical University in May 2008 to April 2010 were divided into observation group (n=162) and control group (n=139). Neonates in observation group were treated with Calsurf and those in control group were not given Calsurf. Hemodynamic parameters including systolic peak velocity

diastolic flow velocity and flow resistance index of the anterior

middle and posterior cerebral arteries as well as the basal artery in observation group and control group were detected by cerebral ultrasonography in 0.5

6

12

24 and 48 h after Calsurf administration and before respirator-aided ventilation

respectively. The gestational age  less than one week and the birth weight  less than 500 g after cerebral ultrasonography were used to match the 2 groups. Severity of RDS suggested on X-ray film was analyzed by paired analysis.     Results    Thirty-three neonates in observation group and 41 neonates in control group were excluded from this study because no complete data was available. The remaining 129 cases in observation group and 98 cases in control group were finally included. Although the peak systolic flow velocity in anterior cerebral artery in 30 min after Calsurf administration and the resistance index of anterior cerebral artery in 12 h after Calsurf administration were lower in observation group than in control group (P0.05)

and no significant difference was observed in cerebral hemodynamic parameters between the two group at most other time points (P0.05).      Conclusion    Slow intravenous injection of Calsurf has no significant effect on cerebral hemodynamics in premature neonates with RDS.