Trial Outcomes & Findings for Bispectral Index (BIS) Versus Electronic Alerts in the Prevention of Anesthesia Awareness: the Michigan Awareness Control Study (NCT NCT00689091)
NCT ID: NCT00689091
Last Updated: 2017-12-07
Results Overview
By modified intention-to-treat analysis
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
22185 participants
Primary outcome timeframe
Outcome of awareness is assessed 30-days after the operation
Results posted on
2017-12-07
Participant Flow
22,185 patients were recruited but 584 were excluded after recruitment due to change in anesthetic technique, case cancellation, withdrawal, or death. Therefore, 21,601 patients were randomized.
Participant milestones
| Measure |
Bispectral Index Group
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
Minimum Anesthesia Contration Alert
This group will receive an alert if total MAC (Minimum Anesthesia Concenration) (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
Overall Study
STARTED
|
10831
|
10770
|
|
Overall Study
COMPLETED
|
9460
|
9376
|
|
Overall Study
NOT COMPLETED
|
1371
|
1394
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Bispectral Index (BIS) Versus Electronic Alerts in the Prevention of Anesthesia Awareness: the Michigan Awareness Control Study
Baseline characteristics by cohort
| Measure |
Bispectral Index Group
n=9 Participants
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
Minimum Anesthesia Concentration Alert
n=9 Participants
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
Total
n=18836 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
53 years
n=5 Participants
|
53 years
n=7 Participants
|
53 years
n=5 Participants
|
|
Sex: Female, Male
Female
|
5,223 Participants
n=5 Participants
|
5,175 Participants
n=7 Participants
|
10398 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
4,237 Participants
n=5 Participants
|
4,201 Participants
n=7 Participants
|
8438 Participants
n=5 Participants
|
PRIMARY outcome
Timeframe: Outcome of awareness is assessed 30-days after the operationBy modified intention-to-treat analysis
Outcome measures
| Measure |
BIS Group
n=9 Participants
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
MAC Alert
n=9 Participants
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
The Percentage of Incidences With Explicit Recall in the BIS Versus MAC Alert Groups.
|
0.08 Percentage of participants/30days
Interval 0.04 to 0.16
|
0.12 Percentage of participants/30days
Interval 0.07 to 0.21
|
SECONDARY outcome
Timeframe: During surgery (45 minutes - 18 hours), measured based on 30 day interviewsBinary variables for whether participants recall dreaming or not.
Outcome measures
| Measure |
BIS Group
n=9376 Participants
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
MAC Alert
n=9460 Participants
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
Number of Participants With Dreams During Anesthesia Compared Between MAC or BIS Monitoring
No dreaming
|
9174 Participants
|
9352 Participants
|
|
Number of Participants With Dreams During Anesthesia Compared Between MAC or BIS Monitoring
Dreaming
|
202 Participants
|
108 Participants
|
SECONDARY outcome
Timeframe: During surgery: (45 minutes - 18 hours)Outcome measures
| Measure |
BIS Group
n=9376 Participants
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
MAC Alert
n=9460 Participants
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
Percentage of Cases With Electronic Alerts
|
2.4 Percentage of cases
Standard Deviation 7.5
|
2.3 Percentage of cases
Standard Deviation 6.6
|
SECONDARY outcome
Timeframe: During surgery (45 minutes - 18 hours)Outcome measures
| Measure |
BIS Group
n=9376 Participants
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
MAC Alert
n=9460 Participants
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
Overall Use of Anesthetics Comparing the BIS to MAC Alerts.
|
0.9 mg
Interval 0.8 to 1.1
|
0.9 mg
Interval 0.8 to 1.1
|
SECONDARY outcome
Timeframe: During recovery room stay: 30 minutes to 6 hoursmeasured in time within Post Anesthesia Care Unit ( PACU) until the participant is ready for discharge from PACU based on a composite of factors, including pain and neurologic status
Outcome measures
| Measure |
BIS Group
n=9376 Participants
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
MAC Alert
n=9460 Participants
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
Time Till Discharge Readiness
|
98 minutes
Interval 66.0 to 140.0
|
95 minutes
Interval 64.0 to 138.0
|
SECONDARY outcome
Timeframe: During recovery room stay: 30 minutes to 6 hoursPopulation: Nausea and vomiting numbers were dependent on nurse reporting; as not all nurses did, the participants analyzed are fewer than the total number in the study.
Outcome measures
| Measure |
BIS Group
n=7329 Participants
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
MAC Alert
n=4707 Participants
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
Number of Participants Without Nausea or Vomiting
No nausea
|
6184 Participants
|
4042 Participants
|
|
Number of Participants Without Nausea or Vomiting
No vomiting
|
7149 Participants
|
4617 Participants
|
SECONDARY outcome
Timeframe: 30 days after surgeryThere is controversy regarding the appropriate technique for assessing awareness during anesthesia with explicit recall. A total cohort was utilized to compare the incidence of awareness with recall as determined by formal interview vs. the incidence of awareness with recall based on spontaneous reports (in the same cohort).
Outcome measures
| Measure |
BIS Group
n=18836 Participants
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
MAC Alert
n=18836 Participants
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
Comparison of the Prospective and Retrospective Approaches to the Study Awareness Incidence.
Yes (awareness with recall)
|
3 participants
|
19 participants
|
|
Comparison of the Prospective and Retrospective Approaches to the Study Awareness Incidence.
No (no awareness with recall)
|
18833 participants
|
18817 participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Outcome of hemodynamic stability is assessedOutcome measures
Outcome data not reported
OTHER_PRE_SPECIFIED outcome
Timeframe: Outcome of mortality is assessedOutcome measures
Outcome data not reported
OTHER_PRE_SPECIFIED outcome
Timeframe: Outcome of post-traumatic stress disorder is assessed with the covariate of awarenessOutcome measures
Outcome data not reported
OTHER_PRE_SPECIFIED outcome
Timeframe: Outcome of hypotension in relationship to induction doses and BIS values will be assessedOutcome measures
Outcome data not reported
OTHER_PRE_SPECIFIED outcome
Timeframe: Outcome of awareness is assessedOutcome measures
Outcome data not reported
OTHER_PRE_SPECIFIED outcome
Timeframe: NEED VALUE HEREOutcome measures
Outcome data not reported
Adverse Events
Bispectral Index Group
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Miniumum Anesthesia Concentration Alert
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Bispectral Index Group
n=9460 participants at risk
This group will have BIS values visible and will receive alerts when the value is \>60.
Bispectral Index Monitor: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
Miniumum Anesthesia Concentration Alert
n=9376 participants at risk
This group will receive an alert if total MAC (including intravenous infusions) is \<0.5 age-adjusted.
Electronic MAC alert: Comparison of two different alerting protocols. One using the bispectral index monitor and one using the MAC alerting protocols.
|
|---|---|---|
|
Cardiac disorders
Non life threatening adverse events
|
0.00%
0/9460
|
0.00%
0/9376
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place