Table 2.
Comparison of bispectral values and anesthetic requirements between groups before and after propensity score matching.
| Variable | Before matching | After matching | ||||
|---|---|---|---|---|---|---|
| Group I (n=66) | Group S (n=95) | P-value | Group I (n=58) | Group S (n=58) | P-value | |
| BIS at baseline | 97 (94–97) | 97 (94–98) | 0.489 | 97 (94–97) | 97 (94–98) | 0.800 |
| BIS at LOC | 75.0±5.5 | n.a. | n.a. | 74.8±5.6 | n.a. | n.a. |
| BIS minimal during surgery | 47.6±6.5 | 38.0±7.3 | 0.000 | 48.1±6.6 | 38.1±7.8 | 0.000 |
| BIS maximal during surgery | 68.2±6.2 | 60.0±6.3 | 0.000 | 68.4±6.4 | 60.3±5.0 | 0.000 |
| BIS average during surgery | 57.9±5.4 | 49.3±5.4 | 0.000 | 58.3±5.6 | 49.2±5.4 | 0.000 |
| Requirements of anesthetics during surgery | ||||||
| Propofol for induction, mg | 75 (57.5–100) | 100 (75–120) | 0.000 | 75 (60–100) | 100 (75–120) | 0.003 |
| Propofol for maintenance, mg·kg−1·h−1 | 3.6±1.4 | 4.5±1.9 | 0.001 | 3.7±1.4 | 4.4±1.9 | 0.013 |
| Sufentanil, μg/kg | 0.62±0.14 | 0.67±0.16 | 0.159 | 0.62±0.14 | 0.66±0.16 | 0.160 |
| Remifentanil, μg·kg−1·h−1 | 4.20 (4.11–4.28) | 4.15 (4.06–4.23) | 0.088 | 4.20 (4.11–4.27) | 4.15 (4.04–4.24) | 0.177 |
| Cisatracurium, mg·kg−1·h−1 | 0.126 (0.124–0.128) | 0.125 (0.123–0.128) | 0.413 | 0.126 (0.124–0.130) | 0.125 (0.123–0.127) | 0.235 |
Values are expressed as median (IQR) or mean±SD. Groups: I, BIS indices maintained at about 10 less than the BIS value at LOC; S, BIS indices maintained at 40–60. LOC – loss of consciousness; BIS – bispectral index; n.a. – not available.