Study Evaluating Whether the Bispectral Index Prevents Patients at Higher Risk From Being Awake During Surgery and Anesthesia

2014-08-27 03:30:26 | BioPortfolio


The overall purpose of this study is to see if a Bispectral Index (BIS) monitor, a Food and Drug Administration (FDA) approved brain monitoring device, will help to reduce the risk of patients remembering being awake during surgery. The BIS monitor may be able to measure how asleep a patient is during surgery. Using the BIS monitor to guide anesthesia will be compared with using the concentration of anesthetic gas to guide anesthesia.


The incidence of anesthesia awareness (AA) is 0.1-0.2% and may result in post traumatic stress disorders. For some patients, owing to illness, medications, substance misuse or surgery, the risk approaches 1%. The B-AWARE Study by Myles et al. suggested that the bispectral index (BIS) monitor, which reportedly reflects anesthetic depth, may decrease the incidence of AA in higher risk patients by 82%. The American Society of Anesthesiologists has published a practice advisory on AA, which does not recommend the routine use of cerebral function monitors. We propose to test the hypothesis that an anesthetic protocol based on BIS decreases the incidence of AA among higher risk patients compared with an anesthetic protocol based on the end-tidal anesthetic gas (ETAG) concentration. We have completed a randomized, single-blinded prospective feasibility study (The B-Unaware Trial) which enrolled 2000 patients at higher risk for AA. Four patients (0.21%; 95% CI=0.06% to 0.57%) had definite AA, of whom two were in the BIS-guided group and two in the ETAG-guided group. Nine patients (0.46%; 95% CI=0.22% to 0.91%) had definite or possible AA, of whom six were in the BIS-guided group and three in the ETAG-guided group. The BAG RECALL study will be a multi-center, prospective, single-blinded, randomized study enrolling 6000 patients at higher risk for AA. The BAG RECALL study is adequately powered and rigorously designed to answer with a reasonable degree of scientific probability whether BIS guidance results in clinically relevant reduction in anesthesia awareness among higher risk patients undergoing general anesthesia.

At the University of Michigan, a parallel study will be conducted - Michigan Awareness Control Study, MACS (NCT00689091) - enrolling 30,000 patients to assess whether the BIS monitor decreases the likelihood of anesthesia awareness among all patients undergoing general anesthesia, regardless of their risk profile. The investigators of this study and the BAG-RECALL study have collaborated in designing these studies and are pre-specifying that common outcome measures will be examined collaboratively including data from both studies.

Study Design

Allocation: Randomized, Control: Active Control, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Prevention


Explicit Recall of Intra-Operative Events


Bispectral index protocol, End tidal anesthetic gas-guided


University of Chicago
United States




Washington University School of Medicine

Results (where available)

View Results


Published on BioPortfolio: 2014-08-27T03:30:26-0400

Clinical Trials [1812 Associated Clinical Trials listed on BioPortfolio]

Bispectral Index Guided Sevoflurane Titration

Electroencephalographic-based monitoring systems such as the bispectral index (BIS) may reduce anaesthetic overdose rates. The investigators hypothesised that goal-directed sevoflurane adm...

Bispectral Index Monitoring of Sedation in Spontaneous Ventilation. Clinical Trial in Scheduled Colonoscopies

The aim of the study is to compare the monitoring of anesthetic depth in colonoscopies using the bispectral index monitor versus conventional monitoring as a guide for sedation, allowing t...

Bispectral-Electroencephalography (EEG) in First Time Hemodialysis

The severity of minimal dialysis disequilibrium syndrome (DDS) is currently detected and graded clinically using clinical criteria. Bispectral Index (BIS), an electroencephalographic (EEG)...

Patient's Satisfaction of Bispectral Index-guided Monitored Anesthesia Care

The investigators will evaluate the effect of bispectral index-guided titration of sedation during ear surgery under monitored anesthesia care on participant's satisfaction with anesthesia...

Bispectral Index to Guide Intubation in Pediatric Anesthesia

This prospective and randomized study aimed to determine the minimal level of Bispectral index needed for quality laryngoscopy before ear, nose and throat surgery in children.

PubMed Articles [8650 Associated PubMed Articles listed on BioPortfolio]

Randomized Feasibility Trial of a Low Tidal Volume-Airway Pressure Release Ventilation Protocol Compared With Traditional Airway Pressure Release Ventilation and Volume Control Ventilation Protocols.

Low tidal volume (= tidal volume ≤ 6 mL/kg, predicted body weight) ventilation using volume control benefits patients with acute respiratory distress syndrome. Airway pressure release ventilation ...

Increasing body mass index steepens the learning curve for ultrasound-guided percutaneous nephrolithotomy.

To define how the learning curve for success in ultrasound-guided PCNL is impacted by body mass index (BMI). Previous research has shown ultrasound-guided percutaneous nephrolithotomy (PCNL) to be an ...

Comparative study of concordance between bispectral index recordings obtained from the standard frontal and infra-orbital sensor position.

Anesthetic challenges and outcomes for procedures in the intraoperative magnetic resonance imaging suite: A systematic review.

Hybrid operating room suites with intraoperative magnetic resonance imaging enable image guided surgery in a fully functional operating room environment. While this environment creates challenges to a...

Ultrasound-Guided, Continuous Brachial Plexus Blockade in a Neonate With Upper Extremity Limb Ischemia: A Case Report.

Regional anesthetic blocks, especially in-dwelling catheters, are infrequently used in neonates and infants. The following report describes a neonate with a gangrenous right upper extremity requiring ...

Medical and Biotech [MESH] Definitions

Drugs administered before an anesthetic to decrease a patient's anxiety and control the effects of that anesthetic.

Imidazole derivative anesthetic and hypnotic with little effect on blood gases, ventilation, or the cardiovascular system. It has been proposed as an induction anesthetic.

A combination of the debris index and the dental calculus index to determine the status of oral hygiene.

The volume of air contained in the lungs at the end of a maximal inspiration. It is the equivalent to each of the following sums: VITAL CAPACITY plus RESIDUAL VOLUME; INSPIRATORY CAPACITY plus FUNCTIONAL RESIDUAL CAPACITY; TIDAL VOLUME plus INSPIRATORY RESERVE VOLUME plus functional residual capacity; or tidal volume plus inspiratory reserve volume plus EXPIRATORY RESERVE VOLUME plus residual volume.

The process whereby a representation of past experience is elicited.

More From BioPortfolio on "Study Evaluating Whether the Bispectral Index Prevents Patients at Higher Risk From Being Awake During Surgery and Anesthesia"

Quick Search


Relevant Topics

Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals. The substance is ingested by an organism ...

Pharmacy is the science and technique of preparing as well as dispensing drugs and medicines. It is a health profession that links health sciences with chemical sciences and aims to ensure the safe and effective use of pharmaceutical drugs. The scope of...

Searches Linking to this Trial