Effects of different levels of hemodilution during extracorporeal circulation on lactic acid and postoperative outcomes in children with congenital heart disease

Objective To study the effects of different levels of hemodilution during extracorporeal circulation(ECC) on the concentration of lactic acid and postoperative outcome in children with congenital heart disease.Methods Sixty children with congenital heart diseases undergoing open heart surgery with ECC were randomly divided into three groups: groupⅠ(n=20) underwent mild hemodilution [Hb(80—90)g/L],groupⅡ(n=20) with medium hemodilution [Hb(70—79)g/L],and groupⅢ(n=20) with deep hemodilution [Hb(60—69)g/L].The concentration of lactic acid and PaO_2 in groupⅡ and group Ⅲ were compared with groupⅠ before ECC,during ECC,after ECC and 24h after the operation.The rate of homologous transfusion during ECC and the postoperative dosage of furosemide were also compared among the three groups.Results The concentrations of lactic acid and PaO2 in the three groups were all within normal range before ECC,during ECC,after ECC and 24h after operation.The homologous transfusion rate during ECC were lower in groupⅡ(30%)and groupⅢ(15%) compared to that of groupⅠ(50%)(P0.05),but the dosage of furosemide in groupⅡ and group Ⅲ was higher than that in groupⅠ(P0.05).Children in all three groups recovered well and had few complications.Conclusion ECC with medium or deep hemodilution [Hb(60—79)g/L]had no adverse effects on lactic acid and postoperative outcome.It may reduce the requirements of homologous transfusion.