Objective:To introduce our experience on extra-operating room anesthesia of children with grave congenital heart diseases during cardiac catheterization an d ventriculography. 　　Methods:Three hundred and sixty-nine children with grave congenital heart d iseases undergoing cardiac catheterization or ventriculography were selected for this study,among whom 86 are presented with left to right shunt and pulmonary a rtery hypertention,11 with pulmonic stenosis and primary pulmonary artery hypert ention,and 272 with right to left shunt.They were routinely fasted before the pr ocedure.O2 Saturation(SpO2) and electrocardiogram were monitored and blood p ressure were recorded.With oxygen inhalated by mask and venous route established ,the children were injected with scolapamine (0.02 mg/kg) and ketamine (1-2 mg /kg) for anesthesia induction.When patients lost conciousness,ketamine (6-8 mg/ kg) and droperidol (0.15-0.30 mg/kg) were given intromascularly for maintaine nce.During the procedure,ketamine (1-2 mg/kg) were given to deepen anethesia. 　　Results:The procedures were fufiled steadily.Eighteen patients presented wit h different kinds of complications such as abdomen distention,vomitting,arrhymia and refractory anoxia to defferent degrees.One patient died,and the mortality w as 0.27%. 　　Conclusions:Anesthesia of children with grave heart diseases during cardiac catheterization and ventriculography is particular.It is important for the anest hesiologists to be familiar with the pathophysiology of heart diseases,and suppl y sufficiant oxygen,keep airway open and unobstructed,avoid stomach regurgitatio n and inhalation and maintain sufficient sedation during the procedure.Oxygen sh ould be given continuously and SpO2 monitored posoperatively to avoid any comp lication.