Working...
ClinicalTrials.gov
ClinicalTrials.gov Menu

Treatment of Traumatic Brain Injury With Hyperbaric Oxygen Therapy

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT00810615
Recruitment Status : Completed
First Posted : December 18, 2008
Results First Posted : August 13, 2018
Last Update Posted : August 13, 2018
Sponsor:
Information provided by (Responsible Party):
George Wolf, San Antonio Military Medical Center

Study Type Interventional
Study Design Allocation: Randomized;   Intervention Model: Parallel Assignment;   Masking: Single (Participant);   Primary Purpose: Treatment
Condition Brain Injury, Chronic
Interventions Other: Hyperbaric oxygen @ 2.4 ATA
Other: Sham treatment
Enrollment 50
Recruitment Details Recruitment occurred from Nov 2008 - Nov 2010. Candidate subjects with a diagnosis of chronic truamatic brain injury (TBI) were identified by DoD neurologists. Those interested were screened for inclusion/exclusion criteria. 103 candidates were screened. 22 did not qualify; 31 were deferred (psychotropic medication or mental status unstable).
Pre-assignment Details  
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures were done up to 5 times per week with a total number of 30 exposures. Pressurization time was seven minutes to a depth of 11 feet of sea water (fsw) or 1.3 ATA. The chamber pressure was slowly decreased over 10 minutes to 6 fsw (1.2 ATA). The final depressurization to surface was done over a 10 minute period. To simulate the treatment 2.4 ATA pressurization, pressurizations and depressurizations were done using venting techniques that would be nearly identical with the noise and temperature as that experienced with the treatment pressure. The inside observers simulated pressure equalization measures (Valsalva) every 10 to 30 seconds and breathed oxygen by mask (required in the 2.4 ATA pressure to prevent decompression sickness) at the same frequency as if they were in the treatment exposure pressure. Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures were done up to 5 times per week with a total number of 30 exposures. Pressurization time was seven minutes to a depth of 45 feet of sea water (fsw) or 2.4 ATA. The final depressurization to surface was done over a 10 minute period. Inside observers used pressure equalization measures (Valsalva) every 10 to 30 seconds and breathed oxygen by mask (required in the 2.4 ATA pressure to prevent decompression sickness) three times (10/15/5 minute durations) during the exposure.
Period Title: Overall Study
Started 25 25
Completed 24 [1] 24 [1]
Not Completed 1 1
Reason Not Completed
Withdrawal by Subject             1             1
[1]
One male withdrawal due to personal reasons.
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA Total
Hide Arm/Group Description Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures were done up to 5 times per week with a total number of 30 exposures. Pressurization time was seven minutes to a depth of 11 feet of sea water (fsw) or 1.3 ATA. The chamber pressure was slowly decreased over 10 minutes to 6 fsw (1.2 ATA). The final depressurization to surface was done over a 10 minute period. To simulate the treatment 2.4 ATA pressurization, pressurizations and depressurizations were done using venting techniques that would be nearly identical with the noise and temperature as that experienced with the treatment leg. The inside observers simulated pressure equalization measures (Valsalva) every 10 to 30 seconds and breathed oxygen by mask (required in the 2.4 ATA pressure to prevent decompression sickness)at the same frequency as if they were in the treatment exposure pressure. Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures were done up to 5 times per week with a total number of 30 exposures. Pressurization time was seven minutes to a depth of 45 feet of sea water (fsw) or 2.4 ATA. The final depressurization to surface was done over a 10 minute period. Inside observers used pressure equalization measures (Valsalva) every 10 to 30 seconds and breathed oxygen by mask (required in the 2.4 ATA pressure to prevent decompression sickness) three times (10/15/5 minute durations)during the exposure. Total of all reporting groups
Overall Number of Baseline Participants 25 25 50
Hide Baseline Analysis Population Description
[Not Specified]
Age, Categorical  
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 25 participants 25 participants 50 participants
<=18 years
0
   0.0%
0
   0.0%
0
   0.0%
Between 18 and 65 years
25
 100.0%
25
 100.0%
50
 100.0%
>=65 years
0
   0.0%
0
   0.0%
0
   0.0%
Age, Continuous  
Mean (Standard Deviation)
Unit of measure:  Years
Number Analyzed 25 participants 25 participants 50 participants
28.4  (7.4) 28.3  (8.1) 28.3  (7.7)
Sex: Female, Male  
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 25 participants 25 participants 50 participants
Female
1
   4.0%
1
   4.0%
2
   4.0%
Male
24
  96.0%
24
  96.0%
48
  96.0%
Region of Enrollment  
Measure Type: Number
Unit of measure:  Participants
United States Number Analyzed 25 participants 25 participants 50 participants
25 25 50
1.Primary Outcome
Title Computer Cognitive Test Scores - ImPACT Verbal Memory
Hide Description The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery was developed at the University of Pittsburgh. It has a sensitivity of 81.9% and specificity of 89.4% in discriminating between concussion and non-concussion groups. It consists of a medical history questionnaire regarding concussions and resultant symptoms including loss of consciousness, memory loss, confusion, headache, seizure activity, emotional state, and sleep patterns. There are four subtests given and scored by computer. These include verbal and visual memory, visual motor speed, and response time. The composite scores are specifically designed to determine changes within the individual, better or worse, over time. The verbal memory score demonstrates improvement as the score increases. The score range was 36.8 to 98.6.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
one subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 70.48  (13.05) 74.21  (12.03)
six weeks post hyperbaric exposure series 78.12  (16.087) 75.36  (15.230)
2.Primary Outcome
Title Posttraumatic Stress Disorder Checklist - Military Version (PCL-M) Scores
Hide Description The PCL-M is a self reported test in which a list of 17 problems and complaints are offered to the individual to score on a 1 to 5 scale with 1 designating “not at all”, 2= “a little bit”, 3= “moderately”, 4= “quite a bit” and 5 designating “extremely”. A sample complaint would be “repeated, disturbing dreams of a stressful military experience”. Hence there is a possible total score range from 17 to 85. For military members, a score of 50 or above is indicative of PTSD. A change from baseline of 5-9 represents a reliable change and change of 10 or greater is a significant change.
Time Frame baseline compared to the change at post hyperbaric exposures (30) series and the six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
Per protocol. The study was a pilot.
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:
Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures were done up to 5 times per week with a total number of 30 exposures. Pressurization time was seven minutes to a depth of 11 feet of sea water (fsw) or 1.3 ATA. The chamber pressure was slowly decreased over 10 minutes to 6 fsw (1.2 ATA). The final depressurization to surface was done over a 10 minute period. To simulate the treatment 2.4 ATA pressurization, pressurizations and depressurizations were done using venting techniques that would be nearly identical with the noise and temperature as that experienced with the treatment pressure. The inside observers simulated pressure equalization measures (Valsalva) every 10 to 30 seconds and breathed oxygen by mask (required in the 2.4 ATA pressure to prevent decompression sickness) at the same frequency as if they were in the treatment exposure pressure.
Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures were done up to 5 times per week with a total number of 30 exposures. Pressurization time was seven minutes to a depth of 45 feet of sea water (fsw) or 2.4 ATA. The final depressurization to surface was done over a 10 minute period. Inside observers used pressure equalization measures (Valsalva) every 10 to 30 seconds and breathed oxygen by mask (required in the 2.4 ATA pressure to prevent decompression sickness) three times (10/15/5 minute durations) during the exposure.
Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline measurement 48.88  (12.59) 50.38  (14.53)
Post 30 hyperbaric exposures -10.125  (10.759) -8.875  (8.789)
6 Week Follow-up -8.292  (10.960) -8.625  (10.761)
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Sham Treatment, Hyperbaric Oxygen 2.4 ATA
Comments ANCOVA, baseline measurement was considered as a covariate and group (sham or 2.4 ATA), treatment (15 treatments, 30 treatments, and 6 weeks) as well as the interaction between group and treatment were considered as the independent variables.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.05
Comments [Not Specified]
Method ANCOVA
Comments A repeated measures model was designed so as to incorporate the adjust for the repeated (dependent) measures within individuals over time.
3.Primary Outcome
Title Computer Cognitive Test Scores - ImPACT Visual Memory
Hide Description The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery was developed at the University of Pittsburgh. It has a sensitivity of 81.9% and specificity of 89.4% in discriminating between concussion and non-concussion groups. It consists of a medical history questionnaire regarding concussions and resultant symptoms including loss of consciousness, memory loss, confusion, headache, seizure activity, emotional state, and sleep patterns. There are four subtests given and scored by computer. These include verbal and visual memory, visual motor speed, and response time. The composite scores are specifically designed to determine changes within the individual, better or worse, over time. The visual memory score demonstrates improvement as the score increases. The score range was 31.2 to 92.7.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
[Not Specified]
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 56.56  (14.86) 59.8  (12.17)
six weeks post hyperbaric exposure series 64.72  (15.19) 66.8  (14.72)
4.Primary Outcome
Title Computer Cognitive Test Scores - ImPACT Processing Speed
Hide Description The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery was developed at the University of Pittsburgh. It has a sensitivity of 81.9% and specificity of 89.4% in discriminating between concussion and non-concussion groups. It consists of a medical history questionnaire regarding concussions and resultant symptoms including loss of consciousness, memory loss, confusion, headache, seizure activity, emotional state, and sleep patterns. There are four subtests given and scored by computer. These include verbal and visual memory, visual motor speed, and response time. The composite scores are specifically designed to determine changes within the individual, better or worse, over time. The Processing Speed score demonstrates improvement as the score increases. The score range was 9.7 to 52.4.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
one subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 30.26  (8.50) 29.62  (9.61)
Six weeks post hyperbaric exposure series 36.71  (10.47) 33.84  (10.30)
5.Primary Outcome
Title Computer Cognitive Test Scores - ImPACT Reaction Time
Hide Description The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery was developed at the University of Pittsburgh. It has a sensitivity of 81.9% and specificity of 89.4% in discriminating between concussion and non-concussion groups. It consists of a medical history questionnaire regarding concussions and resultant symptoms including loss of consciousness, memory loss, confusion, headache, seizure activity, emotional state, and sleep patterns. There are four subtests given and scored by computer. These include verbal and visual memory, visual motor speed, and response time. The composite scores are specifically designed to determine changes within the individual, better or worse, over time. The reaction time score demonstrates improvement as the score decreases. The score range was 0.42 to 1.84.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
one subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 0.739  (0.322) 0.725  (0.199)
Six weeks post hyperbaric exposure series 0.677  (0.186) 0.712  (0.266)
6.Primary Outcome
Title Computer Cognitive Test Scores – BrainCheckers Simple Reaction Time
Hide Description Braincheckers is a PDA version of the Automated Neuropsychological Assessment Metrics (ANAM) supported by the Army Medical Research and Materiel Command in 2000. It was validated against ANAM for the individual tests used. Throughput is defined as correct responses per minute of time available to respond. Higher scores indicate higher accuracy in each of the subtest. The simple reaction time range is 30 to 255.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
One subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 142.21  (60.68) 135.79  (61.48)
Six weeks post hyperbaric exposure series 174.96  (57.75) 171.83  (54.66)
7.Primary Outcome
Title Computer Cognitive Test Scores – BrainCheckers Code Substitution
Hide Description Braincheckers is a PDA version of the Automated Neuropsychological Assessment Metrics (ANAM) supported by the Army Medical Research and Materiel Command in 2000. It was validated against ANAM for the individual tests used. Throughput is defined as correct responses per minute of time available to respond. Higher scores indicate higher accuracy in each of the subtest. The range is 9 to 66. The scores in this section represent results of the code substitution subtest.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
One subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baeline 39.20  (12.08) 37.42  (13.74)
Post hyperbaric exposure 6 week follow up throughp 43.39  (13.56) 40.71  (12.10)
8.Primary Outcome
Title Computer Cognitive Test Scores – BrainCheckers Procedural Reaction Time
Hide Description Braincheckers is a PDA version of the Automated Neuropsychological Assessment Metrics (ANAM) supported by the Army Medical Research and Materiel Command in 2000. It was validated against ANAM for the individual tests used. Throughput is defined as correct responses per minute of time available to respond. Higher scores indicate higher accuracy in each of the subtest. The range is 25 to 118. The scores in this section represent results of the procedural reaction time.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
One subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 81.63  (20.82) 81.17  (21.66)
Post hyperbaric exposure 6 week follow up throughp 85.78  (23.16) 86.78  (16.63)
9.Primary Outcome
Title Computer Cognitive Test Scores – BrainCheckers Go-NoGo Reaction Time
Hide Description Braincheckers is a PDA version of the Automated Neuropsychological Assessment Metrics (ANAM) supported by the Army Medical Research and Materiel Command in 2000. It was validated against ANAM for the individual tests used. Throughput is defined as correct responses per minute of time available to respond. Higher scores indicate higher accuracy in each of the subtest. The range is 41 to 174. The scores in this section represent results of the Go-NoGo reaction time subtest.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
One subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 119.67  (31.03) 116.52  (23.33)
Post hyperbaric exposure 6 week follow up throughp 131.70  (31.43) 129.17  (25.67)
10.Primary Outcome
Title Computer Cognitive Test Scores – BrainCheckers Matching To Sample
Hide Description BrainCheckers is a PDA version of the Automated Neuropsychological Assessment Metrics (ANAM) supported by the Army Medical Research and Materiel Command in 2000. It was validated against ANAM for the individual tests used. Throughput is defined as correct responses per minute of time available to respond. Higher scores indicate accuracy in each of the subtest. The range is 6 to 50. The scores in this section represent results of the matching to sample subtest.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
One subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 20.00  (10.70) 23.71  (11.86)
Post hyperbaric exposure 6 week follow up throughp 28.22  (10.63) 24.42  (8.08)
11.Primary Outcome
Title Computer Cognitive Test Scores – BrainCheckers Code Sub Recall
Hide Description BrainCheckers is a PDA version of the Automated Neuropsychological Assessment Metrics (ANAM) supported by the Army Medical Research and Materiel Command in 2000. It was validated against ANAM for the individual tests used. Throughput is defined as correct responses per minute of time available to respond. Higher scores indicate accuracy in each of the subtest. The range is 6 to 135. The scores in this section represent results of the code sub recall subtest.
Time Frame Baseline and six weeks post hyperbaric exposure series
Hide Outcome Measure Data
Hide Analysis Population Description
One subject withdrawal from each group due to personal reasons
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description:

Subject will breathe air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Sham treatment

Subject will breathe 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Hyperbaric oxygen @ 2.4 ATA: Subject will breath 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures will be done up to 5 times per week with a total number of 30 exposures.

Overall Number of Participants Analyzed 24 24
Mean (Standard Deviation)
Unit of Measure: units on a scale
Baseline 29.88  (16.63) 36.38  (19.77)
Post hyperbaric exposure 6 week follow up throughp 47.57  (24.02) 44.08  (12.07)
12.Secondary Outcome
Title Functional MRI
Hide Description [Not Specified]
Time Frame six weeks post hyperbaric exposure series
Outcome Measure Data Not Reported
13.Secondary Outcome
Title Stem Cells: CD_34
Hide Description A non-parametric regression 14 using the Theil estimator was fit to the observed data in order to demonstrate general trends for relations between measures of cognitive functioning and increased stem cells.
Time Frame six weeks post hyperbaric exposure series
Outcome Measure Data Not Reported
14.Post-Hoc Outcome
Title PCL-M Relative Risk of Improvement of 2.4 ATA Exposures vs. Sham, All Participants With Only One Concussive Event
Hide Description The purpose of a pilot study is to identify potential subgroups who may respond to treatment. The various composite scores were ranked and separated by subject and within groups for those who improved and those who did not. This allowed the application relative risk analysis using MedCalc (http://www.medcalc.org) to identify potential subgroups. Relative Risk of Improvement (RROI) was calculated against the concussion history items. Main categories were the number of concussive events, whether the subject had multiple non-concussive events or not, if there were two concussive events within a 48 hour period, the time expired from the last concussion to consent, the etiology of the event, and loss of consciousness. A concussive event was defined as one immediately followed with symptoms. This outcome measure analyzed PCL-M score decreases of 10 or more (significantly improved) in the individuals who experienced only one concussive event.
Time Frame Baseline values compared to 30 post hyperbaric exposure or 6 week follow-up
Hide Outcome Measure Data
Hide Analysis Population Description
Participants with significant improvement (PCL-M composite scores demonstrating a decrease by 10 or greater) or participants not meeting this criterion.
Arm/Group Title Sham Treatment Improved Sham Treatment Not Improved Hyperbaric Oxygen 2.4 ATA Improved Hyperbaric Oxygen 2.4 ATA Not Improved
Hide Arm/Group Description:

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 4 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 4 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Overall Number of Participants Analyzed 15 9 13 11
Measure Type: Number
Unit of Measure: participants
4 2 4 7
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Sham Treatment Improved, Sham Treatment Not Improved, Hyperbaric Oxygen 2.4 ATA Improved, Hyperbaric Oxygen 2.4 ATA Not Improved
Comments Relative Risk of Improvement in 2.4 ATA group vs. Sham in subjects with one significant event (blast or impact resulting in concussion symptoms) per Concussion History. PCL-M with significant improvement defined as a score decrease 10 or more.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Method of Estimation Estimation Parameter Risk Ratio (RR)
Estimated Value 0.5455
Estimation Comments [Not Specified]
15.Post-Hoc Outcome
Title PCL-M Relative Risk of Improvement of 2.4 ATA Exposures vs. Sham, All Participants With Two Concussive Events
Hide Description The purpose of a pilot study is to identify potential subgroups who may respond to treatment. The various composite scores were ranked and separated by subject and within groups for those who improved and those who did not. This allowed the application relative risk analysis using MedCalc (http://www.medcalc.org) to identify potential subgroups. Relative Risk of Improvement (RROI) was calculated against the concussion history items. Main categories were the number of concussive events, whether the subject had multiple non-concussive events or not, if there were two concussive events within a 48 hour period, the time expired from the last concussion to consent, the etiology of the event, and loss of consciousness. A concussive event was defined as one immediately followed with symptoms. This outcome measure analyzed PCL-M score decreases of 10 or more (significantly improved) in individuals who experienced two concussive events.
Time Frame Baseline values compared to 30 post hyperbaric exposure or 6 week follow-up
Hide Outcome Measure Data
Hide Analysis Population Description
Participants with significant improvement (PCL-M composite scores demonstrating a decrease by 10 or greater) or participants not meeting this criterion.
Arm/Group Title Sham Treatment Improved Sham Treatment Not Improved Hyperbaric Oxygen 2.4 ATA Improved Hyperbaric Oxygen 2.4 ATA Not Improved
Hide Arm/Group Description:

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 4 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 4 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Overall Number of Participants Analyzed 15 9 13 11
Measure Type: Number
Unit of Measure: participants
6 5 3 2
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Sham Treatment Improved, Sham Treatment Not Improved, Hyperbaric Oxygen 2.4 ATA Improved, Hyperbaric Oxygen 2.4 ATA Not Improved
Comments Relative Risk of Improvement in 2.4 ATA group vs. Sham in subjects with two significant events (blast or impact resulting in concussion symptoms) per Concussion History. PCL-M with significant improvement defined as a score decrease 10 or more.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Method of Estimation Estimation Parameter Risk Ratio (RR)
Estimated Value 1.10
Estimation Comments [Not Specified]
16.Post-Hoc Outcome
Title PCL-M Relative Risk of Improvement of 2.4 ATA Exposures vs. Sham, All Participants With Three Concussive Events
Hide Description The purpose of a pilot study is to identify potential subgroups who may respond to treatment. The various composite scores were ranked and separated by subject and within groups for those who improved and those who did not. This allowed the application relative risk analysis using MedCalc (http://www.medcalc.org) to identify potential subgroups. Relative Risk of Improvement (RROI) was calculated against the concussion history items. Main categories were the number of concussive events, whether the subject had multiple non-concussive events or not, if there were two concussive events within a 48 hour period, the time expired from the last concussion to consent, the etiology of the event, and loss of consciousness. A concussive event was defined as one immediately followed with symptoms. This outcome measure analyzed PCL-M score decreases of 10 or more (significantly improved) in individuals who experienced three concussive events.
Time Frame Baseline values compared to 30 post hyperbaric exposure or 6 week follow-up
Hide Outcome Measure Data
Hide Analysis Population Description
Participants with significant improvement (PCL-M composite scores demonstrating a decrease by 10 or greater) or participants not meeting this criterion.
Arm/Group Title Sham Treatment Improved Sham Treatment Not Improved Hyperbaric Oxygen 2.4 ATA Improved Hyperbaric Oxygen 2.4 ATA Not Improved
Hide Arm/Group Description:

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 4 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 4 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Overall Number of Participants Analyzed 15 9 13 11
Measure Type: Number
Unit of Measure: participants
3 2 4 2
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Sham Treatment Improved, Sham Treatment Not Improved, Hyperbaric Oxygen 2.4 ATA Improved, Hyperbaric Oxygen 2.4 ATA Not Improved
Comments Relative Risk of Improvement in 2.4 ATA group vs. Sham in subjects with three significant events (blast or impact resulting in concussion symptoms) per Concussion History. PCL-M with significant improvement defined as a score decrease 10 or more.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Method of Estimation Estimation Parameter Risk Ratio (RR)
Estimated Value 1.1111
Estimation Comments [Not Specified]
17.Post-Hoc Outcome
Title PCL-M Relative Risk of Improvement of 2.4 ATA Exposures vs. Sham, All Participants With Four or More Concussive Events
Hide Description The purpose of a pilot study is to identify potential subgroups who may respond to treatment. The various composite scores were ranked and separated by subject and within groups for those who improved and those who did not. This allowed the application relative risk analysis using MedCalc (http://www.medcalc.org) to identify potential subgroups. Relative Risk of Improvement (RROI) was calculated against the concussion history items. Main categories were the number of concussive events, whether the subject had multiple non-concussive events or not, if there were two concussive events within a 48 hour period, the time expired from the last concussion to consent, the etiology of the event, and loss of consciousness. A concussive event was defined as one immediately followed with symptoms. This outcome measure analyzed PCL-M score decreases of 10 or more (significantly improved) in individuals who experienced four or more concussive events.
Time Frame Baseline values compared to 30 post hyperbaric exposure or 6 week follow-up
Hide Outcome Measure Data
Hide Analysis Population Description
Participants with significant improvement (PCL-M composite scores demonstrating a decrease by 10 or greater) or participants not meeting this criterion.
Arm/Group Title Sham Treatment Improved Sham Treatment Not Improved Hyperbaric Oxygen 2.4 ATA Improved Hyperbaric Oxygen 2.4 ATA Not Improved
Hide Arm/Group Description:

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 4 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 4 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Overall Number of Participants Analyzed 15 9 13 11
Measure Type: Number
Unit of Measure: participants
2 0 2 0
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Sham Treatment Improved, Sham Treatment Not Improved, Hyperbaric Oxygen 2.4 ATA Improved, Hyperbaric Oxygen 2.4 ATA Not Improved
Comments Relative Risk of Improvement in 2.4 ATA group vs. Sham in subjects with four or more significant events (blast or impact resulting in concussion symptoms) per Concussion History. PCL-M with significant improvement defined as a score decrease 10 or more.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Method of Estimation Estimation Parameter Risk Ratio (RR)
Estimated Value 1.0
Estimation Comments [Not Specified]
18.Post-Hoc Outcome
Title PCL-M Relative Risk of Improvement of 2.4 ATA Exposures vs. Sham, All Participants With Multiple Non-concussive Blast and/or Impact Exposures.
Hide Description The purpose of a pilot study is to identify potential subgroups who may respond to treatment. The various composite scores were ranked and separated by subject and within groups for those who improved and those who did not. This allowed the application relative risk analysis using MedCalc (http://www.medcalc.org) to identify potential subgroups. Relative Risk of Improvement (RROI) was calculated for the number of concussive events, whether the subject had multiple non-concussive events or not, if there were two concussive events within a 48 hour period, the time expired from the last concussion to consent, the etiology of the event, and loss of consciousness. Many subjects had multiple blast and/or impact events without a concussion (asymptomatic), but had a flight or flight (danger response) experience. This outcome measure analyzed PCL-M score decreases of 10 or more (significantly improved) in individuals who experienced multiple non-concussive blast and/or impact events.
Time Frame Baseline values compared to 30 post hyperbaric exposure or 6 week follow-up
Hide Outcome Measure Data
Hide Analysis Population Description
Participants with significant improvement (PCL-M composite scores demonstrating a decrease by 10 or greater) or participants not meeting this criterion who had multiple blast and/or impact event that did not result in a concussion (asymptomatic), but had a flight or flight (danger response) experience.
Arm/Group Title Sham Treatment Improved Sham Treatment Not Improved Hyperbaric Oxygen 2.4 ATA Improved Hyperbaric Oxygen 2.4 ATA Not Improved
Hide Arm/Group Description:

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by 9 or less)improvement from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by 9 or less)improvement from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Overall Number of Participants Analyzed 17 7 7 17
Measure Type: Number
Unit of Measure: participants
11 5 2 9
19.Post-Hoc Outcome
Title PCL-M Relative Risk of Improvement of 2.4 ATA Exposures vs. Sham, Measuring Time to Consent From the Last Concussion in Subjects With Multiple Concussions.
Hide Description The purpose of a pilot study is to identify potential subgroups who may respond to treatment. The various composite scores were ranked and separated by subject and within groups for those who improved and those who did not. This allowed the application relative risk analysis using MedCalc (http://www.medcalc.org) to identify potential subgroups. Relative Risk of Improvement (RROI) was calculated for the number of concussive events, whether the subject had multiple non-concussive events or not, if there were two concussive events within a 48 hour period, the time expired from the last concussion to consent, the etiology of the event, and loss of consciousness. This outcome measure analyzed PCL-M score decreases of 10 or more (significantly improved) with consent within one year from the last concussion in subjects who had multiple concussions.
Time Frame Baseline values compared to 30 post hyperbaric exposure or 6 week follow-up
Hide Outcome Measure Data
Hide Analysis Population Description
[Not Specified]
Arm/Group Title Sham Treatment Improved Sham Treatment Not Improved Hyperbaric Oxygen 2.4 ATA Improved Hyperbaric Oxygen 2.4 ATA Not Improved
Hide Arm/Group Description:

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 9 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a significant (decrease by10 or greater)improvement or a reliable (decrease by 5 or greater) from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. See previous description for details.

PCL-M composite scores demonstrated a decrease of 9 or less from baseline at 30 post hyperbaric exposure or 6 week follow-up.

Overall Number of Participants Analyzed 17 7 17 7
Measure Type: Number
Unit of Measure: participants
1 3 3 2
Time Frame [Not Specified]
Adverse Event Reporting Description [Not Specified]
 
Arm/Group Title Sham Treatment Hyperbaric Oxygen 2.4 ATA
Hide Arm/Group Description Subjects breathed air at less than 1.3 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at less that 1.3 ATA. Hyperbaric exposures were done up to 5 times per week with a total number of 30 exposures. Pressurization time was seven minutes to a depth of 11 feet of sea water (fsw) or 1.3 ATA. The chamber pressure was slowly decreased over 10 minutes to 6 fsw (1.2 ATA). The final depressurization to surface was done over a 10 minute period. To simulate the treatment 2.4 ATA pressurization, pressurizations and depressurizations were done using venting techniques that would be nearly identical with the noise and temperature as that experienced with the treatment pressure. The inside observers simulated pressure equalization measures (Valsalva) every 10 to 30 seconds and breathed oxygen by mask (required in the 2.4 ATA pressure to prevent decompression sickness) at the same frequency as if they were in the treatment exposure pressure. Subject breathed 100% oxygen at 2.4 Atmospheres Absolute (ATA) in three 30 minute periods separated by 10 minutes of breathing air at 2.4 ATA. Hyperbaric exposures were done up to 5 times per week with a total number of 30 exposures. Pressurization time was seven minutes to a depth of 45 feet of sea water (fsw) or 2.4 ATA. The final depressurization to surface was done over a 10 minute period. Inside observers used pressure equalization measures (Valsalva) every 10 to 30 seconds and breathed oxygen by mask (required in the 2.4 ATA pressure to prevent decompression sickness) three times (10/15/5 minute durations) during the exposure.
All-Cause Mortality
Sham Treatment Hyperbaric Oxygen 2.4 ATA
Affected / at Risk (%) Affected / at Risk (%)
Total   --/--      --/--    
Show Serious Adverse Events Hide Serious Adverse Events
Sham Treatment Hyperbaric Oxygen 2.4 ATA
Affected / at Risk (%) # Events Affected / at Risk (%) # Events
Total   0/25 (0.00%)      0/25 (0.00%)    
Show Other (Not Including Serious) Adverse Events Hide Other (Not Including Serious) Adverse Events
Frequency Threshold for Reporting Other Adverse Events 5%
Sham Treatment Hyperbaric Oxygen 2.4 ATA
Affected / at Risk (%) # Events Affected / at Risk (%) # Events
Total   4/25 (16.00%)      10/25 (40.00%)    
Ear and labyrinth disorders     
Ear block  [1]  4/25 (16.00%)  8 10/25 (40.00%)  44
Indicates events were collected by systematic assessment
[1]
Ear blocks - subject unable to equalize middle ear pressure during descent requiring the pressurization to be stopped. Blocks/exposures rate - sham: 0.01; treatment: 0.06. Subject post exams with TEED 2 or less using 0-5 scale.
Caveats: Analysis used both repeated measures of analysis of covariance (ANCOVA) and repeated measures analysis of variance (RMANOVA). Due to the results, analysis is currently identifying potential subgroups which may demonstrate significance.
Certain Agreements
All Principal Investigators ARE employed by the organization sponsoring the study.
Results Point of Contact
Name/Title: Dr. George Wolf, Associate Investigator
Organization: San Antonio Military Medical Center, Wilford Hall Ambulatory Surgical Center
Phone: 210-292-3483
Responsible Party: George Wolf, San Antonio Military Medical Center
ClinicalTrials.gov Identifier: NCT00810615     History of Changes
Other Study ID Numbers: FWH20080137H
First Submitted: December 17, 2008
First Posted: December 18, 2008
Results First Submitted: July 23, 2013
Results First Posted: August 13, 2018
Last Update Posted: August 13, 2018