Hyperbaric Oxygen Therapy - Hyperbaric Chamber Information ...

Non-diabetic wounds
Summary
Only one study met entry criteria, Hammarlund and Sundberg’s 51 double-blind,
randomised controlled trial published in 1994. The study was set in Sweden and recruited
16 patients with a median age of 67 years (Range: 42 – 75 years). Patients were enrolled if
they had leg ulcers of more than 1 year’s duration and if these lesions did not show
progress (by inspection) towards healing during the two months prior to the study, if
ankle and first digit blood pressures were within normal ranges, and if they did not
smoke or suffer from a concomitant chronic disease condition such as diabetes mellitus.
The study did not report losses to follow-up and the randomisation method was
inadequately described.
Two balanced groups of 8 subjects were exposed to different concentrations of oxygen
in a multiplace chamber at 2.5 ATA for 90 minutes. The frequency of exposure was five
times a week for a total of 30 sessions. The intervention group was given 100 percent
oxygen while the comparison group received air.
The study looked at the mean changes in wound area over the course of therapy
(Table 20). At four and six weeks, there were statistically significant decreases in the
wound areas of those receiving 100 percent oxygen compared to those receiving air. The
authors also found some indication that improvement continued after hyperbaric
therapies were given, although this occurred only for smaller wounds and results were
based on a much smaller sample size due to drop outs.
Table 20 Percentage decrease in wound area following six weeks of exposure to 100% oxygen or air
in a pressurised chamber (Hammarlund and Sundberg). 51 *
Percentage Decrease in Wound Area (Mean ± SD) †
Week of
Therapy Intervention Group Comparison Group
p
2 6.6 ± 14 2.8 ± 11 0.5557
4 22.0 ± 13 3.7 ± 11 0.0088
6 35.7 ± 17 2.7 ± 11 0.0004
* Abbreviation: SD = standard deviation.
† Compared to baseline (Week 0).
This trial provided some indication that exposure to 100 percent oxygen in a hyperbaric
chamber for lengths up to a month was associated with decreases in the area of chronic,
non-diabetic wounds. However, the study included only small numbers of relatively
tightly-selected subjects and examined only one outcome measure. More studies in
different settings, examining more varied outcomes (eg. absolute wound healing) are
required to provide more generalisable evidence of a treatment effect.
Necrotising soft tissue infections
The review identified six studies that met inclusion criteria for this indication.
This section examines studies that focused on necrotising soft tissue infections in
general. The two following sections examine the effect of HBOT on two specific
diagnoses: necrotising fasciitis and Fournier’s gangrene. These diagnoses were evaluated
separately.
32 Hyperbaric oxygen therapy