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Brain Tissue Oxygen Monitoring in Traumatic Brain Injury (TBI)

Phase 2, Randomized Clinical Trial of the Safety and Efficacy of Brain Tissue Oxygen Monitoring in the Management of Severe Traumatic Brain Injury.

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00974259
Acronym
BOOST 2
Enrollment
122
Registered
2009-09-10
Start date
2009-10-31
Completion date
2014-12-31
Last updated
2019-09-26

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

Conditions

Severe Traumatic Brain Injury

Keywords

Hypoxia, Ischemia, Intracranial hypertension, Neurocritical care

Brief summary

Traumatic brain injury (TBI) is a major cause of death and disability, with an estimated cost of 45 billion dollars a year in the United States alone. Every year, approximately 1.4 million sustain a TBI, of which 50,000 people die, and another 235,000 are hospitalized and survive the injury. As a result, 80,000-90,000 people experience permanent disability associated with TBI. This project is designed to determine whether a device designed to measure brain tissue oxygenation and thus detect brain ischemia while it is still potentially treatable shows promise in reducing the duration of brain ischemia, and to obtain information required to conduct a definitive clinical trial of efficacy. A recently approved device makes it feasible to directly and continuously monitor the partial pressure of oxygen in brain tissue (pBrO2). Several observational studies indicate that episodes of low pBrO2 are common and are associated with a poor outcome, and that medical interventions are effective in improving pBrO2 in clinical practice. However, as there have been no randomized controlled trials carried out to determine whether pBrO2 monitoring results in improved outcome after severe TBI, use of this technology has not so far been widely adopted in neurosurgical intensive care units (ICUs). This study is the first randomized, controlled clinical trial of pBrO2 monitoring, and is designed to obtain data required for a definitive phase III study, such as efficacy of physiologic maneuvers aimed at treating pBrO2, and feasibility of standardizing a complex intensive care unit management protocol across multiple clinical sites. Patients with severe TBI will be monitored with Intracranial pressure monitoring (ICP) and pBrO2 monitoring, and will be randomized to therapy based on ICP along (control group) or therapy based on ICP in addition to pBrO2 values (treatment group). 182 participants will be enrolled at four clinical sites, the University of Texas Southwestern Medical Center/Parkland Memorial Hospital, the University of Washington/Harborview Medical Center, the University of Miami/Jackson Memorial Hospital, and the University of Pennsylvania/Hospital of the University of Pennsylvania. Functional outcome will be assessed at 6-months after injury.

Detailed description

Design and Outcomes This study is a two-arm, single-blind, randomized, controlled, phase II, multi-center pilot trial of the efficacy of pBrO2 monitoring, and is designed to obtain data required for a definitive phase III study, such as efficacy of physiologic maneuvers aimed at normalizing pBrO2. 182 patients with severe TBI who require ICP monitoring will be recruited into this study at 4 clinical sites in the US (Univ. of Texas Southwestern/Parkland Memorial Hospital, Univ. of Washington/Harborview Medical Center, Univ. of Miami/Jackson Memorial Hospital, and Univ. of Pennsylvania/Hospital of the Univ. of Pennsylvania). All patients will have both ICP monitors and pBrO2 monitors inserted through the same burr hole. Half of the patients will be randomized to a treatment protocol based on both ICP and pBrO2 readings, while the control group will be randomized to a treatment protocol based only on ICP readings. The pBrO2monitors of the control arm will be masked, so that the treating physicians will be unaware of the pBrO2 information. Patients will have telephone follow-up interview to assess their level of recovery 6 months post injury, using the Glasgow Outcome Scale-Extended. Interventions and Duration Patients randomized to the control group will have pBrO2 implanted in a similar fashion as patients in the treatment group, but after calibration of the device, the display will be covered with opaque tape. Patients in the control will be treated with a protocol based on ICP measures only. Patients in the treatment group (both ICP and pBrO2 measures are visible) will be treated according to a protocol that incorporates both ICP and pBrO2 measures. The treatment protocols are based on current standards of care, but are described in detail to insure uniformity in treatments across the 4 study sites. The probe will remain in place for a maximum or 5 days, until all values are normal for 48 hours, or sooner if a complication arises. If the patient has normal values, monitors will be removed after 48 hours. Objectives Primary Objective: The prescribed treatment protocol, based on pBrO2 monitoring, results in reduction of the fraction of time that brain oxygen levels are below the critical threshold of 20 mm Hg in patients with severe traumatic brain injury. Secondary Objectives: * Safety hypotheses: Adverse events associated with pBrO2 monitoring are rare. * Feasibility hypotheses: Episodes of decreased pBrO2 can be identified and treatment protocol instituted comparably across 4 clinical sites, and protocol violations will be low (\<10%) and uniform across different clinical sites. * Non-futility hypothesis: A relative risk of good outcome measured by the Glasgow Outcome Scale-Extended 6 months after injury of 2.0 is consistent with the results of this phase II study.

Interventions

DEVICEManagement protocol based on pBrO2 and ICP values.

For patients who experience falls in pBrO2 below 20 mm Hg, a hierarchical treatment algorithm will be instituted, adapted from published recommendations49. In principle, episodes requiring therapy will fall into one of 4 scenarios (scenario A, B, C, and D, defined in figure 7), which will require different management strategies. The treatment protocol depends on which type of episode is being treated. Treatment is triggered by abnormalities in either ICP (\> 20 mm Hg) or pBrO2 (\< 20 mm Hg) are noted. Elevations in ICP above 20 mm Hg or decline in pBrO2 below 20 mm Hg for more than 5 minutes will trigger a treatment intervention. Treatment is directed to an episode. Patients may start in one type of episode and move to another. Therapy will depend on which type of episode they are in at any given time.

DEVICEManagement protocol based on ICP values only.

For the patients randomized to ICP treatment alone, only Scenario A and Scenario B episodes are relevant.

Sponsors

University of Washington
CollaboratorOTHER
University of Miami
CollaboratorOTHER
University of Pittsburgh
CollaboratorOTHER
Duke University
CollaboratorOTHER
Ohio State University
CollaboratorOTHER
Temple University
CollaboratorOTHER
Thomas Jefferson University
CollaboratorOTHER
University of Cincinnati
CollaboratorOTHER
National Institute of Neurological Disorders and Stroke (NINDS)
CollaboratorNIH
University of Pennsylvania
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No

Inclusion criteria

1. Non-penetrating traumatic brain injury 2. Requirement for intracranial pressure monitoring according to Guidelines for the Management of Severe TBI, as operationalized below: * GCS 3-8 (measured off sedatives or paralytics) with abnormal CT scan. If patient is intubated, motor GCS \< 4 required. * If CT scan normal, motor GCS \< 4 (measured off sedatives or paralytics) * Intoxication is not a reason for deferring ICP monitoring if above criteria are met. * If the patient has a witnessed seizure, wait 30 minutes to evaluate GCS. 3. Randomization and placement of monitors within 12 hours of injury. 4. Males and females Age 18-70 years, English or Spanish speaking patients.

Exclusion criteria

1. Specific clinical contraindications: * GCS motor score \> 4 with normal CT scan * Bilaterally absent pupillary responses 2. Laboratory contraindications per safety considerations: Coagulopathy that makes insertion of parenchymal monitors contraindicated (Platelets \< 50,000/mL, INR \> 1.4) (Enrollment allowed if coagulopathy can be corrected before 12 hour post-injury deadline). 3. Pregnant females will be excluded. Blood test for pregnancy is a routine part of care in ED's. However, if not done, a urine or blood test will be done as a safety precaution after consent but prior to study treatment. 4. Monitoring with pBrO2 monitor prior to randomization. 5. Clinical, demographic and other characteristics that precludes appropriate diagnosis, treatment or follow-up in the trial. * Systemic sepsis at the time of screening * Refractory hypotension (SBP \< 70 mm Hg for \> 30 minutes) * Refractory systemic hypoxia (paO2 \< 60 mm Hg on FiO2 \< 0.5) * Evidence of premorbid disabling conditions that interfere with outcome assessment. These include diagnosis of Alzheimer's disease, Parkinson's disease, multiple sclerosis, spinal cord injury with deficits, history of stroke, brain tumors, chronic use of medication for disabling neurologic or psychiatric disorder, or history of suicide attempt within the past year. * Imminent death or current life-threatening disease * Prisoner * Individuals who hold religious beliefs against blood transfusion * Previous TBI hospitalization greater than 1 day * Patients who are unlikely to be available for follow-up interview, even by telephone. for example, patients who are homeless, illegal aliens, or live in foreign countries and those with whom future personal (including family) or telephone contact is unlikely. 6. Active drug or alcohol use or dependence that, in the opinion of the stie investigator, would interfere with follow-up. 7. Imminent death or current life-threatening disease 8. Inability or unwillingness of subject or legal guardian/representative to give written informed consent 9. Participation in other observational or interventional clinical trials is allowed as long as the PI of each study agree ahead of time to allow co-enrollment.

Design outcomes

Primary

MeasureTime frameDescription
Fraction of Time That Brain Oxygen Levels Are Below the Critical Threshold of 20 mm Hg .5 daysProportion of time PbtO2 below 20 mm Hg

Secondary

MeasureTime frameDescription
Total Number Participants With Adverse Events Associated With PbtO2 Monitoring.5 daysTotal number participants with PbtO2 directed intervention-related Serious Adverse Events
Adherence to PbtO2 and ICP-directed Treatment Protocol5 daysNumber of protocol deviations and violations for ICP/PbtO2 group and ICP only group. The unit of measure for this outcome is number of events, where an event can be either a deviation or a violation.
Relative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.6 monthsDichotomized Glagow Outcome Score-Extended: GOSE 1-4 = Poor Outcome GOSE 5-8 = Good Outcome GOSE is a 8-point scale, with 1 = death, 8 = full recovery.

Countries

United States

Participant flow

Recruitment details

Patients with severe TBI who required ICP monitoring were screened at 10 Level 1 trauma centers . Patients admitted with an initial GCS greater than 8 who deteriorated neurologically (within 48 hr of injury) from a presumptive could also be enrolled provided randomization and ICP monitor placement occurred within 12 hours of deterioration.

Participants by arm

ArmCount
pBrO2 and ICP Management
Treatment protocol based on pBrO2 and ICP values. Management protocol based on pBrO2 and ICP values.: For patients who experience falls in pBrO2 below 20 mm Hg, a hierarchical treatment algorithm will be instituted, adapted from published recommendations49. In principle, episodes requiring therapy will fall into one of 4 scenarios (scenario A, B, C, and D, defined in figure 7), which will require different management strategies. The treatment protocol depends on which type of episode is being treated. Treatment is triggered by abnormalities in either ICP (\> 20 mm Hg) or pBrO2 (\< 20 mm Hg) are noted. Elevations in ICP above 20 mm Hg or decline in pBrO2 below 20 mm Hg for more than 5 minutes will trigger a treatment intervention. Treatment is directed to an episode. Patients may start in one type of episode and move to another. Therapy will depend on which type of episode they are in at any given time.
57
ICP Management
Treatment protocol based on ICP values only. Management protocol based on ICP values only.: For the patients randomized to ICP treatment alone, only Scenario A and Scenario B episodes are relevant.
62
Total119

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyTechnically inadequate PbtO2 recordings21

Baseline characteristics

CharacteristicpBrO2 and ICP ManagementICP ManagementTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
57 Participants62 Participants119 Participants
Age, Continuous37.8 years
STANDARD_DEVIATION 17.2
36.2 years
STANDARD_DEVIATION 17.5
37.0 years
STANDARD_DEVIATION 17.3
Craniectomy12 Participants18 Participants30 Participants
Glasgow Come Scale-Motor3.6 units on a scale
STANDARD_DEVIATION 1.5
3.7 units on a scale
STANDARD_DEVIATION 1.5
3.7 units on a scale
STANDARD_DEVIATION 1.5
Injury Type--Closed Head Injury56 Participants62 Participants118 Participants
Race/Ethnicity, Customized
Black
9 Participants11 Participants20 Participants
Race/Ethnicity, Customized
Other
2 Participants2 Participants4 Participants
Race/Ethnicity, Customized
Unknown
3 Participants0 Participants3 Participants
Race/Ethnicity, Customized
White
47 Participants53 Participants100 Participants
Sex: Female, Male
Female
11 Participants16 Participants27 Participants
Sex: Female, Male
Male
46 Participants46 Participants92 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
13 / 5718 / 62
other
Total, other adverse events
48 / 5755 / 62
serious
Total, serious adverse events
27 / 5734 / 62

Outcome results

Primary

Fraction of Time That Brain Oxygen Levels Are Below the Critical Threshold of 20 mm Hg .

Proportion of time PbtO2 below 20 mm Hg

Time frame: 5 days

ArmMeasureValue (MEAN)Dispersion
pBrO2 and ICP ManagementFraction of Time That Brain Oxygen Levels Are Below the Critical Threshold of 20 mm Hg .0.15 ProportionStandard Deviation 0.21
ICP ManagementFraction of Time That Brain Oxygen Levels Are Below the Critical Threshold of 20 mm Hg .0.44 ProportionStandard Deviation 0.31
Secondary

Adherence to PbtO2 and ICP-directed Treatment Protocol

Number of protocol deviations and violations for ICP/PbtO2 group and ICP only group. The unit of measure for this outcome is number of events, where an event can be either a deviation or a violation.

Time frame: 5 days

ArmMeasureGroupValue (NUMBER)
pBrO2 and ICP ManagementAdherence to PbtO2 and ICP-directed Treatment ProtocolDeviation: ICP 20-25 for > 30 min w/o Rx95 Events (sum of deviations & violations)
pBrO2 and ICP ManagementAdherence to PbtO2 and ICP-directed Treatment ProtocolDeviation: PbtO2 15-19 for > 30 min w/o Rx24 Events (sum of deviations & violations)
pBrO2 and ICP ManagementAdherence to PbtO2 and ICP-directed Treatment ProtocolViolation: ICP > 25 for > 30 min w/o Rx7 Events (sum of deviations & violations)
pBrO2 and ICP ManagementAdherence to PbtO2 and ICP-directed Treatment ProtocolViolation: PbtO2 < 15 for > 30 min w/o Rx17 Events (sum of deviations & violations)
ICP ManagementAdherence to PbtO2 and ICP-directed Treatment ProtocolViolation: PbtO2 < 15 for > 30 min w/o Rx0 Events (sum of deviations & violations)
ICP ManagementAdherence to PbtO2 and ICP-directed Treatment ProtocolDeviation: ICP 20-25 for > 30 min w/o Rx71 Events (sum of deviations & violations)
ICP ManagementAdherence to PbtO2 and ICP-directed Treatment ProtocolViolation: ICP > 25 for > 30 min w/o Rx14 Events (sum of deviations & violations)
ICP ManagementAdherence to PbtO2 and ICP-directed Treatment ProtocolDeviation: PbtO2 15-19 for > 30 min w/o Rx0 Events (sum of deviations & violations)
Secondary

Relative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.

Dichotomized Glagow Outcome Score-Extended: GOSE 1-4 = Poor Outcome GOSE 5-8 = Good Outcome GOSE is a 8-point scale, with 1 = death, 8 = full recovery.

Time frame: 6 months

ArmMeasureGroupValue (NUMBER)
pBrO2 and ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 113 participants
pBrO2 and ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 21 participants
pBrO2 and ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 37 participants
pBrO2 and ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 410 participants
pBrO2 and ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 54 participants
pBrO2 and ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 65 participants
pBrO2 and ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 76 participants
pBrO2 and ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 87 participants
ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 82 participants
ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 118 participants
ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 54 participants
ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 22 participants
ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 74 participants
ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 35 participants
ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 65 participants
ICP ManagementRelative Risk of Good Outcome of ICP/PbtO2 Group Compared to ICP Only Group.GOSE 412 participants
Secondary

Total Number Participants With Adverse Events Associated With PbtO2 Monitoring.

Total number participants with PbtO2 directed intervention-related Serious Adverse Events

Time frame: 5 days

ArmMeasureGroupValue (NUMBER)
pBrO2 and ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Cardiovascular SAEs9 participants
pBrO2 and ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Gastro-intestinal SAEs1 participants
pBrO2 and ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Neurological SAEs5 participants
pBrO2 and ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Respiratory SEAs4 participants
pBrO2 and ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Other SAEs8 participants
pBrO2 and ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Death Following withdrawal of medical care8 participants
ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Other SAEs17 participants
ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Cardiovascular SAEs8 participants
ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Respiratory SEAs1 participants
ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Gastro-intestinal SAEs1 participants
ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Death Following withdrawal of medical care14 participants
ICP ManagementTotal Number Participants With Adverse Events Associated With PbtO2 Monitoring.Neurological SAEs10 participants

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