Hyperbaric Oxygen Therapy - Hyperbaric Chamber Information ...

tinnitus (6 versus 3 subjects). None of the results reached commonly accepted levels of
statistical significance.
In patients with chronic disorders, the authors found no significant differences between
intervention and comparison groups when examining the proportions who reported
improvement in hearing after 15 sessions (33% versus 50%; p = 0.2525) or in those who
reported improvements in subjective tinnitus (18% versus 41%; p = 0.0944).
The main results offered by Cavallazzi et al 95 are puzzling because the text and tables
provided different numbers. Not enough data was given to arrive at a definite answer.
The intervention was found to promote recovery if therapy was started within 72 hours
(intervention group: 95% versus comparison group: 71%) or if the subject’s audiogram
trended downward (intervention group: 80% versus comparison group: 33%), but no
denominator data were provided to judge adequately the variation in these results.
Moreover, the post-hoc nature of these differences should be recognised.
Vavrina et al 96 was the only study that reported statistically significant improvements in
the average absolute gain in hearing. The intervention group improved by (Mean ± SD)
121.3 ± 61.8 decibels compared to the 74.3 ± 57.68 decibel improvement in the
comparison group. The difference of 47 decibels (95% CI = 20.03, 73.97 decibels) was
highly statistically significant (p = 0.0009). However, the study was also the only one to
use a retrospective observational design among the four.
As with the lack of objective definitions for the conditions, none of these studies
provided operational definitions for “improvement” or “recovery”. The terms were used
loosely to describe changes in scores or measures but the magnitude of these changes
was unclear.
Summary
The studies provided conflicting evidence of the efficacy of HBOT in the management
of sudden deafness and acoustic trauma. Methodological problems were common in the
identified studies. Until more rigorous evidence is collected, the use of HBOT in the
management of these conditions cannot be supported on the basis of the current
inconsistent results.
Cancer
Hyperbaric oxygen therapy as an adjunctive agent is examined for cancers of the head
and neck, cervix, and bladder. Other cancers include lymphomas and neoplasms affecting
the lungs and nervous system. For most neoplastic indications, the comparator
treatments are of historical interest and not relevant to current practice.
Head and neck cancer
Nine studies were retrieved from the published literature. A brief description of each
study is given in Table 61.
Hyperbaric oxygen therapy 61