Abstract: PURPOSE: To compare the effect of three different general anesthetic maintenance drugs: propofol intravenous, sevoflurane inhalation and propofol intravenous injection combined with sevoflurane in halation, on serum homocysteine (Hcy) concentration in infants undergoing long-term operation. METHODS: Fifty-one children aged 8-24 months with operation time more than 3 hours were randomly divided into three groups: group P（propofol intravenous injection), group S（sevoflurane inhalation) and group C（propofol intravenous injection combined with sevoflurane inhalation).All the infants underwent rapid induction transoral endotracheal intubation, and the dosage of anesthesia maintenance drugs in each group was adjusted according to the depth of anesthesia during operation. Venous blood was collected at the beginning of the operation (T₀) and immediately after the end of the operation (T₁), to determine the serum hcyconcentration(Hcy). Preoperative and postoperative Hcy concentrations and their changes in each group were compared. Statistical analysis was performed using SPSS 21.0 software package. RESULTS: Compared with the preoperative period, HR of the infants in all three groups were significantly decreased (P<0.05), but there was no significant difference in NIBP and SpO₂.Compared with preoperative level, serum Hcy concentration of group C decreased significantly after operation(P<0.01), while there was no significant difference between group S and group P. There was no significant difference between the three groups in Hcy concentration at T₀ and T₁(P>0.05). CONCLUSIONS: Propofol and sevoflurane alone or combined with anesthesia maintenance in infants with long-term operation has little effect on serum Hcy concentration.

Key words: Infant, Sevoflurane, Propofol, Homocysteine, Long-term operation