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The SOMNUS Study: Sedative Optimization Via Monitoring Neurological Status

A Randomized Control Trial Using the BIS Monitor to Avoid Over Sedation and Prolonged Neuropsychological Deficits in Mechanically Ventilated ICU Patients

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00469482
Acronym
SOMNUS
Enrollment
28
Registered
2007-05-04
Start date
2007-06-30
Completion date
2016-09-30
Last updated
2018-03-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cognitive Impairment, Critically Ill, Delirium

Keywords

Delirium, Cognitive Impairment, Sleep, Polysomnography, Sedation, Mechanical Ventilation, Critical Illness

Brief summary

A combined strategy of Richmond Agitation and Sedation Scale (RASS) clinical targeting plus bispectral index (BIS) guided sedation in mechanically ventilated, critically ill patients will decrease time on mechanical ventilation, decrease the duration of intensive care unit (ICU) delirium and coma, and will improve subacute neurocognitive function when compared to sedation guided by RASS targeting alone.

Detailed description

Sedatives and analgesics are used to maintain comfort in almost all mechanically ventilated patients. Unfortunately, these medications also have many deleterious effects. Sedatives increase time on mechanical ventilation, have adverse hemodynamic effects, disturb sleep architecture, and have been determined to be an independent risk factor for ICU delirium. Delirium is an independent determinant of longer hospital stay, higher costs, and higher mortality, and the presence of delirium is highly predictive of long-term neurocognitive deficits. In consideration of these facts, better methods are needed to guide sedation, avoid oversedation, and possibly reduce delirium. Current guidelines recommend titration of sedation to a goal level based on bedside evaluation using a validated assessment tool, e.g. the Richmond Agitation and Sedation Scale. These assessment tools, however, are underused and many ICU patients are oversedated with well described consequences. A practical method by which to determine where a patient lies may prove beneficial in optimizing our delivery of sedatives and improving patient outcomes. While conventional EEG monitoring is not practical in the ICU, bispectral index (BIS) monitoring may be easily used in this clinical setting. BIS monitoring may provide a means to assess sedation level in unresponsive or paralyzed ICU patients and to decrease the total amount of sedatives/analgesics administered. Additional benefits of a combined clinical sedation scale and BIS-monitoring approach could include a decreased incidence and/or duration of delirium as well as a decreased incidence and severity of ICU-associated prolonged neurocognitive deficits. The specific aims of this study are as follows: Aim 1: To determine if sedative and analgesic medication delivery guided by clinical sedation scales and BIS monitor parameters of over-sedation will decrease time on mechanical ventilation. Aim 2: To determine if sedative and analgesic medication delivery guided by clinical sedation scales and BIS monitor parameters of over-sedation will decrease the duration of delirium and coma when compared to the use of clinical sedations scales alone. Aim 3: To determine if sedative and analgesic medication delivery guided by clinical sedation scales and BIS monitor parameters of over-sedation will decrease the incidence and severity of subacute cognitive impairment when compared to the use of clinical sedation scales alone. Aim 4: To characterize polysomnography findings in critically ill patients at various BIS levels. Aim 5: To determine if poor sleep quality is a factor in post critical illness neurocognitive dysfunction.

Interventions

OTHERSedation,RASS Targeted plus BIS Monitoring

Providing patient sedation utilizing standard of care methods (RASS) plus BIS monitoring

OTHERSedation, RASS Targeted

Patient sedation utilizing standard of care methods (RASS targeted)

Sponsors

Medtronic - MITG
CollaboratorINDUSTRY
Vanderbilt University Medical Center
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Male or female adult patients admitted to the ICU for critical illnesses requiring mechanical ventilation with expectation of being mechanically ventilated for greater than 24 hours. Subjects must have an actual or a target RASS of -3 or deeper with 48 hours of initiation of mechanical ventilation.

Exclusion criteria

* Subjects who are less than 18 years old. * Inability to obtain informed consent from the patient or his/her surrogate. * Subjects admitted with alcohol or drug overdoses, suicide attempts, or alcohol/delirium with tremors. * Subjects with documented moderate to severe dementia. * Subjects with anoxic brain injuries, strokes, neurotrauma, or neuromuscular disorders such as myasthenia gravis or Guillain Barre syndrome. * Subjects whose family and/or physician have not committed to aggressive support for 72 hours or who are likely to withdraw within 72 hours. * Subjects who are moribund or are not expected to survive hospital discharge due to preexisting uncorrectable medical condition. * Subjects who have either Child-Pugh Class B or C cirrhosis.

Design outcomes

Primary

MeasureTime frame
Number of ventilator free hours and dayswhile in ICU, appoximately 3-7 days

Secondary

MeasureTime frameDescription
Incidence of subacute cognitive dysfunction using RBANS- Repeatable Battery for the Assessment of Neuropsychological Status,3 months
Incidence of subacute cognitive dysfunction using TRAILS A&B3 months
Incidence of subacute cognitive dysfunction using SF-36 - Short Form Health Survey3 months
Incidence of subacute cognitive dysfunction using MMSE - Mini Mental State Examination3 months
Incidence of subacute cognitive dysfunction using IADLs - instrumental activities of daily living3 months
Incidence of subacute cognitive dysfunction using AD8- ADL - activities of daily living3 months
Incidence of subacute cognitive dysfunction using APACHE II - Acute Physiologic and Chronic Health Evaluation II score3 months
Number of delirium and coma free dayswhile in ICU, appoximately 3-7 days)
Hospital length of staywhile in hospital, usually 5-10 days
Six month mortality6 months
Biomarkers for neurological injury and inflammation, Neuron-Specific Enolase (NSE)Baseline, Day 3 and at Ventilator removal (appoximately day 3-7)
Biomarkers for neurological injury and inflammation, S100Baseline, Day 3 and at Ventilator removal (appoximately day 3-7)
Biomarkers for neurological injury and inflammation, IL-6Baseline, Day 3 and at Ventilator removal (appoximately day 3-7)
Biomarkers for neurological injury and inflammation, C Reactive Protein (CRP)Baseline, Day 3 and at Ventilator removal (appoximately day 3-7)
sleep qualitywithin 24 hours of enrollment through day 3-7measured with continuous polysomnography
ICU length of staywhile in ICU, appoximately 3-7 days

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026