Trial Outcomes & Findings for Neuroimaging During Pure Oxygen Breathing (NCT NCT03268590)

Last Updated: 2019-11-13

Results Overview

Change in brain blood flow from Baseline Room Air breathing (21% inspired oxygen) to Pure Oxygen breathing (100% inspired oxygen). Measured using Magnetic Resonance Imaging (MRI).

Recruitment status

COMPLETED

Study phase

PHASE4

Target enrollment

33 participants

Primary outcome timeframe

Baseline and at 30 minutes

Results posted on

2019-11-13

Participant Flow

41 persons responded to study advertisements and were screened for eligibility between September 2017 and April 2018. 33 were studied.

Participant milestones

Participant milestones
Measure	All Study Participants Persons will undergo MRI, EEG, and complete computerized cognitive testing in baseline room air. Persons will then breathe 100% pure oxygen and undergo MRI, EEG, and complete computerized cognitive testing. Persons will serve as their own controls.
Overall Study STARTED	33
Overall Study COMPLETED	32
Overall Study NOT COMPLETED	1

Reasons for withdrawal

Reasons for withdrawal
Measure	All Study Participants Persons will undergo MRI, EEG, and complete computerized cognitive testing in baseline room air. Persons will then breathe 100% pure oxygen and undergo MRI, EEG, and complete computerized cognitive testing. Persons will serve as their own controls.
Overall Study Previously unknown exclusion criteria	1

Baseline Characteristics

Neuroimaging During Pure Oxygen Breathing

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	All Study Participants n=33 Participants Breathing 21% and 100% oxygen via non-rebreather face mask Oxygen: Persons will undergo MRI, EEG, and complete computerized cognitive testing in baseline room air. Persons will next breathe 100% pure oxygen and undergo MRI, EEG, and complete computerized cognitive testing. Persons will serve as their own controls.
Age, Continuous	39.61 years STANDARD_DEVIATION 13.80 • n=5 Participants
Sex: Female, Male Female	14 Participants n=5 Participants
Sex: Female, Male Male	19 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	2 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	31 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	1 Participants n=5 Participants
Race (NIH/OMB) White	30 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	2 Participants n=5 Participants
Region of Enrollment United States	33 participants n=5 Participants
BMI	26.68 kg/m^2 STANDARD_DEVIATION 4.15 • n=5 Participants

PRIMARY outcome

Timeframe: Baseline and at 30 minutes

Population: Participants with usable MRI arterial spin labeling (ASL) data

Change in brain blood flow from Baseline Room Air breathing (21% inspired oxygen) to Pure Oxygen breathing (100% inspired oxygen). Measured using Magnetic Resonance Imaging (MRI).

Outcome measures

Outcome measures
Measure	All Study Participants n=30 Participants All Persons will undergo MRI, EEG, and complete computerized cognitive testing in baseline room air. Persons will next breathe 100% pure oxygen and undergo MRI, EEG, and complete computerized cognitive testing. Persons will serve as their own controls.
Cerebral Blood Flow 21% oxygen cerebral perfusion	48.54 ml/min/100g tissue Standard Deviation 12.78
Cerebral Blood Flow 100% oxygen cerebral perfusion	36.17 ml/min/100g tissue Standard Deviation 11.97

SECONDARY outcome

Timeframe: Baseline and at 30 minutes

Population: Participants with usable MRI ASL (arterial spin labeling) data

Change in alpha cortical electrical activity in the temporal brain region from Baseline Room Air breathing (21% inspired oxygen) to Pure Oxygen breathing (100% inspired oxygen). Measured using MRI-compatible 64-electrode high-density electroencephalography (EEG).

Outcome measures

Outcome measures
Measure	All Study Participants n=30 Participants All Persons will undergo MRI, EEG, and complete computerized cognitive testing in baseline room air. Persons will next breathe 100% pure oxygen and undergo MRI, EEG, and complete computerized cognitive testing. Persons will serve as their own controls.
Cortical Network Activity 21% oxygen spectral power temporal alpha activity	6.15 microvolt/second Standard Error 0.34
Cortical Network Activity 100% oxygen spectral power temporal alpha activity	6.75 microvolt/second Standard Error 0.45

SECONDARY outcome

Timeframe: Baseline and at 30 minutes

Change in cognitive performance from Baseline Room Air breathing (21% inspired oxygen) to Pure Oxygen breathing (100% inspired oxygen). Measured using the General Cognitive Function score on the MicroCog\^TM Assessment of Cognitive Functioning (TM= trademark of Pearson Education, Inc., New York, NY). The computer-administered MicroCog measures changes in cognitive performance in 9 domains related to attention, memory, reasoning, spatial processing, and reaction time. The General Cognitive Function score is a summed score and measures accuracy and speed processing. Education-adjusted Standardized Scores used to compare each study participant against population norms. Higher scores are indicative of better performance. Index Standardized Scores of 69 and below are considered Below Average; scores of 70-84 are considered Low Average; scores of 85-114 are considered to be Average; and scores of 115 and above are considered to be Above Average.

Outcome measures

Outcome measures
Measure	All Study Participants n=30 Participants All Persons will undergo MRI, EEG, and complete computerized cognitive testing in baseline room air. Persons will next breathe 100% pure oxygen and undergo MRI, EEG, and complete computerized cognitive testing. Persons will serve as their own controls.
Cognitive Performance 21% oxygen cognitive assessment	97.91 score on a scale Standard Error 2.22
Cognitive Performance 100% oxygen cognitive assessment	221.70 score on a scale Standard Error 2.49

Adverse Events

All Study Participants When Breathing Room Air

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

All Study Participants When Breathing Pure Oxygen

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Michael John Decker, PhD

Case Western Reserve University

Phone: 216-368-2467

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee Funding source is the United States Air Force Research Laboratories. The AFRL must approve any presentation or publication of the study results before they can be disseminated.
Publication restrictions are in place

Restriction type: OTHER