Neurocritical Care

, 11:20 | Cite as

A Randomized Evaluation of Bispectral Index-Augmented Sedation Assessment in Neurological Patients

  • DaiWai M. OlsonEmail author
  • Suzanne M. Thoyre
  • Eric D. Peterson
  • Carmelo Graffagnino
Original Article



To assess whether monitoring sedation status using bispectral index (BIS) as an adjunct to clinical evaluation was associated with a reduction in the total amount of sedative drug used in a 12 h period.


Prospective randomized controlled clinical trial.


Tertiary care neurocritical care unit.


Sixty-seven mechanically ventilated adult patients receiving continuous intravenous sedation with propofol.


Sedation monitoring using clinical assessment with the Ramsay scale (Ramsay-alone group) or clinical assessment plus BIS monitoring (BIS-augmentation group). Subjects were randomized to Ramsay-alone (n = 35), or BIS-augmentation (n = 32). Nurses adjusted the dose of propofol to a Ramsay of 4, or a Ramsay of 4 and BIS between 60 and 70.

Measurements and Main Results

Patients in the BIS-augmentation group received significantly less propofol by volume (93.5 ml vs. 157.8 ml, respectively; P < .015), and had lower infusion rates (14.6 vs. 27.9 mcg/kg/min; P = .003). There is a lower risk of propofol infusion exceeding manufacturer’s recommended dosing guides in the BIS-augmentation group versus the Ramsay-alone group (0 vs. 23%, P = .0052). The BIS-augmentation group woke up much quicker than those in the Ramsay-alone group (1.2 vs. 7.5 min; P < .0001).


BIS-augmented sedation monitoring resulted in a marked reduction in the total dose of sedative used to achieve the same level of clinical sedation resulting in shortened time to wake up without any measurable adverse effects. Physiologic sedation assessment tools may provide a useful means of improving the care of sedated critically ill patients.


Sedation assessment Nursing care Critical care Neurofunction monitoring Neurocritical care 



This research is supported by NIH T32 NR07091 Interventions to Prevent and Manage Chronic Illness and Aspect Medical Systems, Inc.


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Copyright information

© Humana Press Inc. 2009

Authors and Affiliations

  • DaiWai M. Olson
    • 1
    Email author
  • Suzanne M. Thoyre
    • 2
  • Eric D. Peterson
    • 3
  • Carmelo Graffagnino
    • 4
  1. 1.Department of Medicine-NeurologyDuke University Medical CenterDurhamUSA
  2. 2.School of NursingUniversity of North Carolina at Chapel HillChapel HillUSA
  3. 3.Division of Cardiology, Duke Clinical Research InstituteDuke University Medical CenterDurhamUSA
  4. 4.Division of Neurology, Neuroscience Intensive Care UnitDuke University Medical CenterDurhamUSA

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