Bispectral index monitoring of conscious sedation with the combination of meperidine and midazolam during endoscopy.
background & aims: Current practice guidelines strongly recommend differentiation of deep from moderate sedation during endoscopy. Standard methods of sedation monitoring are labor-intense. Bispectral index monitoring (BIS) is widely used during anesthesia, but its benefits during conscious sedation are controversial. Thus, we performed a prospective observational study to assess its ability for detecting deep sedation during endoscopy.


METHODS
Patients presenting for elective outpatient endoscopy were monitored simultaneously with the Modified Observer's Assessment of Alertness and Sedation (MOAA/S) and BIS. A combination of a narcotic and benzodiazepine was used, with the target being moderate sedation and analgesia. Deep sedation was defined by MOAA/S score of 1-2 and BIS score of <or=75. With MOAA/S as the reference standard, the accuracy of BIS for detecting deep sedation was evaluated.


RESULTS
A total of 775 simultaneous observations of BIS and MOAA/S scores were recorded on 76 patients. Deep sedation, defined by MOAA/S and BIS, was seen in 204 (26%) and 92 (12%) observations, respectively. BIS correlated poorly with deep sedation (rho, -0.02; 95% confidence interval [CI], -0.16-0.12). The sensitivity, specificity, and positive and negative predictive values (95% CI) for detecting deep sedation were 29.6 (23.4-36.3), 94.9 (92.8-96.6), 68.2 (57.4-77.7), and 78.6 (75.3-81.7), respectively.


CONCLUSIONS
BIS has a low accuracy for detecting deep sedation as a result of a considerable overlap of scores across the sedation levels. Further refinements in BIS are needed to differentiate deep from moderate sedation for future studies on conscious sedation.
Section of Therapeutic Endoscopy, Department of Gastroenterology and Hepatology, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
Mohammed A
MA
Qadeer
John J
JJ
Vargo
Sandeep
S
Patel
John A
JA
Dumot
A Rocio
AR
Lopez
Patricia A
PA
Trolli
Darwin L
DL
Conwell
Tyler
T
Stevens
Gregory
G
Zuccaro
D000759:Adjuvants, Anesthesia / Q000494:pharmacology*; D000368:Aged; D000553:Ambulatory Care; D016292:Procedural Sedation; D054810:Deep Sedation; D004359:Drug Therapy, Combination; D016145:Endoscopy, Digestive System; D005260:Female; D006801:Humans; D008297:Male; D008614:Meperidine / Q000494:pharmacology*; D008874:Midazolam / Q000494:pharmacology*; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity
D000759:Adjuvants, Anesthesia; D008614:Meperidine; D008874:Midazolam