Awareness during general anesthesia despite simultaneous bispectral index and end-tidal anesthetic gas concentration monitoring

The exposure of infants and children to volatile anesthetics, such as sevoflurane, has been a topic of concern with respect to the potential risk for long term neurocognitive effects. The primary objective of this study was to determine whether the perioperative utilization of Bispectral Index (BIS) monitoring alters the sevoflurane delivery and exposure to children. This is a prospective randomized trial of two groups of healthy ambulatory day surgery patients (2 to 12 years). The patients in both groups had the BIS applied soon after the induction of general anesthesia, but only the anesthesiologists in the group randomized to BIS visible were able to see the BIS values. All of the patients received general anesthesia with sevoflurane. This study found no difference in the overall exposure to sevoflurane between both groups (mean end-tidal sevoflurane level of 1.8 in both groups, P = 084). The duration of time in the recovery room, the time to meet discharge criteria, the Pediatric Agitation Emergence Delirium (PAED) scores and the Face, Legs, Activity, Cry, Consolability (FLACC) scores were not statistically different between the groups. The application and utilization of intraoperative BIS monitoring does not alter the sevoflurane administration nor the discharge readiness nor the recovery profile in healthy ambulatory children.

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The Effect of Bispectral Index Monitoring on End-Tidal Gas Concentration and Recovery Duration After Outpatient Anesthesia

Anesthesia & Analgesia ◽

10.1097/00000539-200109000-00017 ◽

2001 ◽

Vol 93 (3) ◽

pp. 613-619 ◽

Cited By ~ 43

Author(s):

D. Janet Pavlin ◽

Jae Y. Hong ◽

Peter R. Freund ◽

Meagan E. Koerschgen ◽

Janet O. Bower ◽

...

Keyword(s):

Bispectral Index ◽

Gas Concentration ◽

Recovery Duration ◽

Bispectral Index Monitoring ◽

End Tidal

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The Effect of Bispectral Index Monitoring on End-Tidal Gas Concentration and Recovery Duration After Outpatient Anesthesia

Survey of Anesthesiology ◽

10.1097/00132586-200208000-00004 ◽

2002 ◽

Vol 46 (4) ◽

pp. 185-186

Author(s):

Lydia A. Conlay

Keyword(s):

Bispectral Index ◽

Gas Concentration ◽

Recovery Duration ◽

Bispectral Index Monitoring ◽

End Tidal

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Bispectral Index Monitoring (BIS) as a Guide for Intubation Without Neuromuscular Blockade in Office-Based Pediatric General Anesthesia: A Retrospective Evaluation

Anesthesia Progress ◽

10.2344/0003-3006-58.1.3 ◽

2011 ◽

Vol 58 (1) ◽

pp. 3-7 ◽

Cited By ~ 3

Author(s):

Zakaria S Messieha ◽

Samuel Guirguis ◽

Sherine Hanna

Keyword(s):

General Anesthesia ◽

Neuromuscular Blockade ◽

Bispectral Index ◽

Index System ◽

Muscle Relaxation ◽

Pediatric Anesthesia ◽

Vital Signs ◽

Mean Value ◽

American Society ◽

End Tidal

The Bispectral Index System is a useful guide for timing of adequate intubation conditions in office-based pediatric general anesthesia without neuromuscular blockade. As the number of cases in the office-based setting increase, many clinicians opt to intubate patients without neuromuscular blockade to avoid airway complications associated with skeletal muscle relaxation. Conventionally, this technique is conducted using the traditional monitoring criteria of vital signs, end-tidal inhalation agents, as well as anesthesiologist timing and knowledge of the pharmacodynamics of the anesthetic agent to help determine the proper depth of anesthesia for adequate intubating conditions. This study retrospectively assesses the use of the Bispectral Index System (BIS) as a guide for timing of nonparalytic tracheal intubation in pediatric office-based general anesthesia. Anesthetic records for 168 children, American Society of Anesthesiology physical status I and II, and ranging in age from 18 months to 17 years were retrospectively analyzed. Intubation outcomes were based on 6 preset criteria to reflect the adequacy of the technique. The mean BIS value during the time of intubation was 34.7. There were no complications encountered. A BIS mean value of 34.7 provided adequate intubation conditions without muscle relaxation in office-based pediatric anesthesia without complications.

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Epidural Lidocaine Decreases Sevoflurane Requirement for Adequate Depth of Anesthesia as Measured by the Bispectral Index ® Monitor

Anesthesiology ◽

10.1097/00000542-200105000-00018 ◽

2001 ◽

Vol 94 (5) ◽

pp. 799-803 ◽

Cited By ~ 109

Author(s):

Peter S. Hodgson ◽

Spencer S. Liu

Keyword(s):

General Anesthesia ◽

Epidural Anesthesia ◽

Bispectral Index ◽

Depth Of Anesthesia ◽

Intravenous Lidocaine ◽

Lidocaine Group ◽

Plasma Lidocaine ◽

Intravenous Saline ◽

End Tidal ◽

To Receive

Background Epidural anesthesia potentiates sedative drug effects and decreases minimum alveolar concentration (MAC). The authors hypothesized that epidural anesthesia also decreases the general anesthetic requirements for adequate depth of anesthesia as measured by Bispectral Index (BIS). Methods After premedication with 0.02 mg/kg midazolam and 1 microg/kg fentanyl, 30 patients aged 20-65 yr were randomized in a double-blinded fashion to receive general anesthesia with either intravenous saline placebo or intravenous lidocaine control (1-mg/kg bolus dose; 25 microg x kg(-1) x min(-1)). A matched group was prospectively assigned to receive epidural lidocaine (15 ml; 2%) with intravenous saline placebo. All patients received 4 mg/kg thiopental and 1 mg/kg rocuronium for tracheal intubation. After 10 min of a predetermined end-tidal sevoflurane concentration, BIS was measured. The ED50 of sevoflurane for each group was determined by up-down methodology based on BIS less than 50 (MAC(BIS50)). Plasma lidocaine concentrations were measured. Results The MAC(BIS50) of sevoflurane (0.59% end tidal) was significantly decreased with lidocaine epidural anesthesia compared with general anesthesia alone (0.92%) or with intravenous lidocaine (1%; P < 0.0001). Plasma lidocaine concentrations in the intravenous lidocaine group (1.9 microg/ml) were similar to those in the epidural lidocaine group (2.0 microg/ml). Conclusions Epidural anesthesia reduced by 34% the sevoflurane required for adequate depth of anesthesia. This effect was not a result of systemic lidocaine absorbtion, but may have been caused by deafferentation by epidural anesthesia or direct rostral spread of local anesthetic within the cerebrospinal fluid. Lower-than-expected concentrations of volatile agents may be sufficient during combined epidural-general anesthesia.

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Application of Bispectral Index® and Narcotrend® Index to the Measurement of the Electroencephalographic Effects of Isoflurane with and without Burst Suppression

Anesthesiology ◽

10.1097/00000542-200410000-00008 ◽

2004 ◽

Vol 101 (4) ◽

pp. 847-854 ◽

Cited By ~ 42

Author(s):

Sascha Kreuer ◽

Jörgen Bruhn ◽

Reinhard Larsen ◽

Ulrich Grundmann ◽

Steven L. Shafer ◽

...

Keyword(s):

General Anesthesia ◽

Bispectral Index ◽

Visual Assessment ◽

Burst Suppression ◽

Pharmacodynamic Modeling ◽

Effect Compartment ◽

Medical Systems ◽

Prediction Probability ◽

End Tidal ◽

Narcotrend Index

Background The Narcotrend monitor (MonitorTechnik, Bad Bramstedt, Germany) has recently been introduced as an intraoperative monitor of anesthetic state, based on a classification scheme originally developed for visual assessment of the electroencephalogram. The authors compared the performance of the Narcotrend index (software version 4.0) to the Bispectral Index (BIS, version XP; Aspect Medical Systems, Natick, MA) as electroencephalographic measures of isoflurane drug effect during general anesthesia. Methods The authors observed 15 adult patients scheduled to undergo radical prostatectomy with a combined epidural-isoflurane general anesthesia technique. At least 45 min after induction of general anesthesia, during a phase of constant surgical stimulation, end-tidal isoflurane concentrations were varied between 0.5 and 2.0 multiples of minimum alveolar concentration, and the BIS and the Narcotrend index were recorded. The prediction probability (PK) was calculated for the BIS and the Narcotrend index to predict isoflurane effect compartment concentration for each measure. The correlation analysis of the BIS and the Narcotrend index with the isoflurane effect compartment concentration was obtained by pharmacodynamic modeling based on two sigmoidal curves to account for the discontinuity in both indices with the onset of burst suppression. Results The prediction probabilities were indistinguishable (BIS PK = 0.72 +/- 0.07 (mean +/- SD); range, 0.61-0.84; Narcotrend index PK = 0.72 +/- 0.10; range, 0.51-0.87), as were the correlations between the electroencephalographic measures and isoflurane effect compartment concentrations (BIS R = 0.82 +/- 0.12; Narcotrend index R = 0.85 +/- 0.09). The pharmacodynamic models for the BIS and the Narcotrend index yielded nearly identical results. Conclusions The BIS and the Narcotrend index detected the electroencephalographic effects of isoflurane equally. Combining two fractional sigmoid Emax models adequately described the data before and after the onset of burst suppression.

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