Objective:To summarize the anesthesia experience of open heart surgery in 43 infants(weigh less than 5kg) and to explore the related issues with myocardioprotection and brain protection.Methods:Conventional induction of anesthesia

nasotracheal intubation

arteriovenous puncture

cardiopulmonary bypass were established

according to the needs for maintaining the body low temperature(deep

middle

superficial);haemodynamics was maintained with vasoactive agent after aorta was opened.Results:Two infants with transposition of conducting arteries succumbed to stoma leak.One infant with tetralogy of Fallot succumbed to low cardiac output syndrome

bellows complication appeared in 8 cases

Ⅲ.atrial ventricular block 1

and the rest infants recovered well.Mortality was 6.98%in this group.Conclusion:Cardiac anesthesia control in infants with low weight is difficult

death rate is hiqh and complication is complex.Butas long as control is done well

mortality omd complitation can be devreased.