Abstract:

Objective To investigate the feasibility of using bispectral index(BIS) monitor to inspect anesthesia depth in pediatric patients. Methods Forty pediatric patients(American Society of Anesthesiologists(ASA) Ⅰ-or Ⅱ) undergoing general anesthesia, tracheal intubation and elective surgery were recruited. Anesthesia was induced by the intravenous injection with propofol/remifentanil; maintained by the intravenous infusion with propofol/remifentanil. Patients were classified by age into four groups(10 in each): A(≤3 mo）, B（＞3 mo to 2 yr）, C(>2 yr to 6 yr), and D(>6 yr to 12 yr). Sedation was assessed by the University of Michigan Sedation Scale(UMSS), and BIS value was recorded before the induction(T1), after the induction(T2), at tracheal intubation(T3), at skin incision（T4）, at discontinuation of intravenous propofol/remifentanil（T5）, at the evidence of spontaneous respiration（T6） and at tracheal extubation(T7). Postanesthesia spontaneous respiration recovery time(from T5 to T6) and postanesthesia extubation time(from T5 to T7) were recorded. Results (1) UMSS scores were 0~1 at T1, increased since T2, 4 at T4, decreased to 0~1 at T7 as seen at T1, in a group. Correspondingly, (2) BIS values were above 96% at T1; decreased since T2(P<0.01); increased to the level of T1 at T7, in a group. (3) Average postanesthesia extubation time was longer(P<0.01) in group A than those in groups B, C or D. (4) Average post-anesthesia spontaneous respiration recovery times were not significantly different between any pair of two groups. Conclusion BIS is an indicator of anesthesia depth in pediatric patients undergoing general anesthesia by the propofol/reminfentanil program.

Key words: propofol, remifentanil, bispectral index, UMSS score