Objectives
1
Describe the impact of inappropriate sedation in the critical care setting
2
Identify challenges with sedation assessment
3
Describe the basic technology of Bispectral Index (BIS™) monitoring
4
State the key applications for BIS monitoring in the ICU
Sedation: Current Issues
Without a means to
objectively titrate
the level of sedation,
patients may be:
Over-sedated
• increased drug costs
• delayed weaning
• increased ICU length of stay
• increased testing
Under-sedated
• anxiety and agitation
• awareness and recall
• post-traumatic stress disorder
• increased adverse events
• increased use of paralytics
Incidence of Inappropriate Sedation
Olson D. et al.
2003
Kaplan L. and Bailey H.
2000
15.4%
20%
10%
30.6%
54%
70%
Over-sedation
On Target
Under-sedation
Kaplan L and Bailey H. Critical Care. 2000; 4(1):S110.
Olson D et al. NTI Proceedings. 2003; CS82:196.
Components of Comfort
Vital Signs + Sedation Scales + BIS Monitoring
Consciousness/Sedation
COMFORT
Analgesia
Autonomic & Somatic
Response + Pain Scales
Muscle
Relaxation
Movement +
Nerve Stimulator
Bispectral Index (BIS)
A practical, processed EEG parameter that measures the direct effects
of sedatives on the brain
Frontal montage
Provides objective information about an individual patient’s response
to sedation
Numerical scale correlates to sedation endpoints
Optimizes sedation assessment and titration
GE BIS Display / BIS Sensor
GE BIS Display
BIS Sensor
Philips BIS Display / BIS Sensor
Philips BIS Display
BIS Sensor
BIS Technology
BIS Monitor
BIS Modules
BIS Sensor
Sensor Application
Apply sensor on forehead at angle
Circle #1: Centered, 2 inches above nose
Circle #4: Directly above eyebrow
Circle #3: On temple, between corner of eye
and hairline
Press around the edges of each circle to assure adhesion
Press each circle for 5 seconds
BIS Range Guidelines
Titration of sedatives to BIS ranges should be dependent upon the individual
goals for sedation that have been established for each patient.
These goals and associated BIS ranges may vary over time, in the context of
patient status and treatment plan.
BIS in the ICU: Key Applications
Objective assessment of sedation during:
Mechanical
Ventilation
Neuromuscular
Blockade
Drug Induced
Coma
Bedside
Procedures
Moderate/Deep Sedation During
Mechanical Ventilation
Challenges/Concerns
•Over-sedation
• longer wake-up
• increased MV time
• increased drug costs
• increased length of stay
• Under-sedation
• anxiety, agitation
• failure to effectively ventilate
• unintended medical device
removal
• NMBA use when adequate
sedation cannot be achieved
• Inadequacy of sedation
assessment tools
BIS Value
• Objective measure of
level of sedation
• Improved drug titration
• May avoid use of NMBA
with better controlled
sedation
• Help reduce adverse events
associated with over- and
under-sedation
BIS in Deep Sedation
• Titration to maximal Ramsay Score of 6 (unarousable)
• Blinded BIS monitoring
100
90
2
3
70
60
68
6
50
BIS
4
6
45
40
6
Ramsay
31
30
5
6
Ramsay Score*
BIS Value
80
20
10
0
Day 1
Day 3
Day 5
Results:
• Ramsay Score remains the same, with significant decrease of BIS values over time.
• Data suggest possible accumulation of sedatives and inherent risks of over-sedation.
Jaspers et al. Intensive Care Medicine. 1999;25(Suppl 1):S67.
* Mondello et al. Minerva Anestesiology. 2002;68(102):37-43.
BIS in Deep Sedation
Bispectral Index (BIS)
• Titration to unarousable state by subjective scale
• Blinded BIS monitoring
100
90
80
70
60
50
40
30
20
10
0
SAS 1
Ramsay 6
Unarousable
Results:
• Patients were unarousable at maximal sedation score.
• All patients appeared similar clinically, but displayed wide variation in
sedation level as measured objectively with BIS monitoring.
Riker. AJRCCM 1999
De Deyne. Int Care Med 1998
BIS in the ICU: Reduces Sedative Cost
Maintains Adequate Sedation
Neurocritical Care Unit at Duke University Hospital
Compared cost of propofol pre-BIS monitoring vs. BIS-guided titration
Results:
• Average Cost Savings: $185/patient/day
• All patients were considered adequately sedated
Annual savings (2 patients/day): > $135,000
Olson D et al. Critical Care Nurse. 2003; 23(3):45-52.
Neuromuscular Blockade
Challenges/Concerns
• Under-sedation / Awareness
• Over-sedation / Extended
wake-up
• Inability to use traditional
subjective sedation
assessment tools
BIS Value
• Provides objective
information where sedation
scales can not be used
• More information to assure
proper sedation dosage
• Monitors for the risk of
awareness
• Provides reassurance to
staff and family
78% Decrease
18% Decrease
$900
$800
$700
$819
$600
$669
$500
$400
$300
$200
$100
$0
Control
BIS Titrated
Patient Recall:
Frightened / Painful (%)
Sedative Cost / patient ($)
BIS Reduces Sedative Cost & Improves Patient Experience
20%
18%
16%
18%
14%
12%
10%
8%
6%
4%
4%
2%
0%
Control
BIS Titrated
SICU patients (n=57): Infusions of sedatives & paralytics
Control: Sedatives titrated to vital signs and comfort
BIS: Sedatives titrated to BIS 70-80 (post-stimulation)
BIS-Guided Titration Results:
• Average sedative savings of $150 per patient
• Unpleasant recall reduced from 18% to 4% (p<0.05)
Kaplan L and Bailey H. Critical Care. 2000; 4(1):S110.
Drug Induced Coma
Challenges/Concerns
• Traditional EEG monitoring is:
• complex
• costly
• difficult to interpret
• Ongoing assessment is
critical to assure targeted
suppression
BIS Value
• Simplified interpretation
of patient response
to treatment
• Improve drug titration
with continuous, objective
information
Burst Suppression EEG Pattern
Pentobarbital Coma (15 sec)
250
200
150
SAS 1
BIS 14
100
50
0
-50
-100
-150
-200
-250
Riker RR et al. Pharmacotherapy. 2003; 23(9):1087-1093.
SR 67
Bedside Procedures
Challenges/Concerns
BIS Value
• Patients are too sick or
unstable to transport to OR
• Improves quality of
care by optimizing sedation
• Need to assure same
standard of care for patients
regardless of location
• Allows same standard
of care for surgical
procedures
• Risks associated with overand under-sedation
• Monitors for risk of
awareness
• Over-sedation / Delayed
recovery
• Under-sedation / Awareness
• Cost savings potential
BIS: Procedural Monitoring
Bispectral Index (BIS)
• Sedation drugs and doses administered at discretion of bronchoscopist
• Bronchoscopists blinded to BIS values
100
*
90
80
*
*
*
70
Too Awake
Less Recall
95% Limits
60
50
*= p<0.05
40
Base
Start
Low
1st Dx
Mean Dx
End
Time during Bronchoscopy
Results:
• Patients who recalled feeling “too awake” were less sedated as measured by the
BIS, despite receiving similar sedative doses.
• Physicians performing bronchoscopy usually overestimate the adequacy of
sedation compared to patients experiencing bronchoscopy.
Riker RR, Vijay P, Prato BS. Patient Recall After Bronchoscopy Corresponds to EEG Monitoring
(Bispectral Index) But Not Sedative Drug Doses. American Journal Respiratory Critical Care
Medicine 1997; 155: A397.
Value of BIS in the ICU
Objective sedation assessment
Minimize
consequences
of over- and
under-sedation
Improve
quality of
sedation
management
Optimize clinical
and economic
outcomes
For more information about
clinical applications for BIS monitoring
in critical care,
please contact Aspect Medical Systems, Inc.
USA: 1 888 247 4633
Outside USA: +31 30 662 9140
www.aspectmedical.com
Bispectral Index, the BIS logo and BIS are trademarks of Aspect Medical
Systems, Inc. and are registered in the USA, EU and other countries.
©2004, Aspect Medical Systems, Inc.
080-0386 1.00