Correlation analysis between encephlogram pain index and bispectral index during procedural sedation and analgesia

ObjectiveTo analyze and evaluate the correlation between encephlogram pain index(PI) and bispectral index(BIS) during procedural sedation and analgesia.

MethodsA total of 100 patients scheduled by plastic surgery under procedural sedation and analgesia, aged 18-53(grade Ⅰ or Ⅱ the American Society of Anesthesiologists were selected.All patients were anesthetized with intravenous injection of single 0.04 mg/kg of midazolam at the beginning of anesthesia, and continuous intravenous infusion of dexmedetomidine(loading dose for 1 μg/kg, followed by 0.4 to 0.7 μg·kg^-1·h^-1) and remifentanil(0.1 μg·kg^-1·min^-1) at the same time.After the BIS value was sustained from 60 and 80, the dilating fluid was injected into the surgical site for local anesthesia.The PI and BIS value in all patients were measured and recorded at the beginning of local anesthesia and surgery(T₁ and T₂), after 30 min and 60 min of anesthesia induction(T₃ and T₄), immediately after turning off dexmedeto midine infusion(T₅) and at the end of surgery(T₆) using BIS VISTA monitor and HXD-I multi-function combined monitor, respectively.The correlation between PI and BIS at each time-point was analyzed.

ResultsAt the time points of T₁-T₆, the PI value was significantly positively correlated with BIS value(r=0.633-0.798, P < 0.05).

ConclusionsDuring procedural sedation and analgesia, the PI value is significantly correlated with BIS value.The PI value increases or decreases with the increasing and decreasing of BIS value(lightening or deepening of sedation), which suggests that the PI value can be used as a good monitor to assess the effectiveness of procedural sedation and analgesia.