Katja Hübl1, Matej Makovec2
Hyperbaric Oxygen Promotes Wound Healing
and Reduces the Risk of Amputation
ABSTRACT
KEY WORDS: hyperbaric oxygenation, chronic wound, gangrene, chronic limb-threatening ischemia
BACKGROUNDS. The aim of this pilot study was to determine the benefits of hyperbaric
oxygen (HBO) therapy for chronic wounds in patients with chronic limb-threatening ischemia
(CLTI). METHODS. The study was performed as a retrospective cohort study, with five
patients with CLTI included. Patients were treated with HBO after endovascular treat-
ment (EVT). Treatment sessions involved daily exposure to high oxygen at higher-than-
-atmospheric pressures in a hyperbaric chamber. RESULTS. Out of five patients with CLTI,
three had diabetes, while two did not. Following EVT, three patients underwent toe-level
amputations, and two required a debridement of necrotic tissue. HBO therapy adminis-
tered post-EVT enhanced wound healing, eliminating the need for further amputations
in all five patients. DISCUSSION. The treatment of chronic wounds in patients with CLTI
requires a multidisciplinary approach. HBO therapy can be used as an adjunctive therapy
to the standard therapy modality, as it can increase the healing rate of wounds and reduce
the number of amputations.
1 Katja Hübl, Kajori Center, Maribor, Sokolska ulica 46, 2000 Maribor; kajori@siol.net
2 Asist. dr. Matej Makovec, dr. med., Oddelek za vaskularno in endovaskularno kirurgijo, Univerzitetni klinični center
Maribor, Ljubljanska ulica 5, 2000 Maribor
11Med Razgl. 2024; 63 Suppl 2: 11–14 • doi: 10.61300/angb22
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BACKGROUNDS
Hyperbaric oxygen (HBO) therapy promotes
the healing of ischemic wounds by utilizing
high levels of oxygen to achieve anti-
microbial effects and stimulating long-term
neovascularization (1–3). This treatment can
be particularly beneficial for patients with
chronic limb-threatening ischemia (CLTI)
and nonhealing wounds. The most common
cause of peripheral arterial disease leading
to CLTI is atherosclerosis, which is fre-
quently associated with arterial hyperten-
sion, hypercholesterolemia, smoking, and
diabetes mellitus. In these patients, non-
healing wounds typically develop in areas
of foot trauma caused by improperly fitting
shoes or injuries (2). Treating nonhealing
wounds in CLTI patients requires a multi-
disciplinary approach, with the primary
goal being limb preservation. However,
many patients still require amputation (3).
Revascularization therapy (RT) can often
limit the need for major amputations, instead
resulting in minor amputations, such as at
the toe level, which generally preserves
ambulatory functions. Although revascular-
ization is necessary, it can sometimes cause
the spread of infection due to remaining
gangrene or necrotic tissue. Consequently,
early debridement of necrotic tissue or minor
amputation of gangrenous areas is usually
recommended soon after the revasculariza-
tion procedure (3).
HBO therapy involves the intermittent
inhalation of 90–100% oxygen at a pressure
higher than 1atm absolute. HBO therapy
favourably increases the amount of oxygen
dissolved in arterial blood and leads to
hyperoxia even in poorly perfused tissues
(4–6).
A minimal skin perfusion pressure (SPP)
of over 40 mmHg is generally required for
a planned minor amputation, such as at the
toe level, after RT. However, higher peri-
operative SPP values in patients with SPP
above 40 mmHg are associated with better
success rates for the procedure (3).
The duration and number of HBO ther-
apy sessions patients typically receive
depend on specific protocols tailored to each
individual. Each person and condition are
unique, so the protocol is determined by
a hyperbaric medicine specialist. Hyperbaric
treatment sessions can range from one to
two hours (7). Most treatments are admin-
istered once a day, five days a week, and can
continue for several weeks. In severe cases,
sessions may occur twice daily. Non-heal-
ing wounds typically require an average of
25–40 therapy sessions (7).
METHODS
The study was conducted as a retrospective
cohort study. It included five patients with
CLTI accompanied by ulcers or gangrene who
received HBO therapy following successful
endovascular treatment (EVT) at the
University Medical Centre Maribor between
December 2022 and November 2023. HBO
therapy was administered at 1.5 atm with
90% oxygen for 90 minutes per session
daily, except on weekends, for 20–40 sessions.
Wound healing was assessed at the
end of HBO therapy and again six months
after treatment. Outcomes were determined
based on the results of wound healing.
Complete wound closure without any leak-
age was considered a successful healing out-
come. Both healing and minor amputations
were regarded as favourable outcomes.
Conversely, no improvement or major ampu-
tations were considered as unfavourable
outcomes.
RESULTS
The study involved five patients with CLTI
(three males, two females) with an average
age of 64.2 ± 7.3 years (table 1), which were
all previously treated at the University
Medical Centre Maribor. There was no cli-
nical improvement in any leg treated with
technically successful EVT. The average
number of HBO sessions was 42.0 ± 23.9.
HBO chamber treatments began a few days
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after EVT for all but one patient, with an
average start time of 8.7±5.9 days post-EVT.
Toe-level amputations were performed in
three patients after EVT, and necrotic tis-
sue debridement was required in two limbs.
All patients responded positively to
the treatment. The introduction of hyper-
baric oxygenation halted the progression of
gangrene, and after three weeks of daily
treatments, the wounds became clean and
began to show signs of healing. Upon treat-
13Med Razgl. 2024; 63 Suppl 2:
ment completion, the wounds were suc-
cessfully healed (figure 1). Pain relief was
typically achieved after an average of six
sessions, and over 90% of patients experi-
enced an improvement in their ability to
walk without discomfort. In addition to
standard wound healing assessments for the
legs, we conducted quality of life evalua-
tions through patient interviews. We
observed improved vitality and well-being
in all patients.
Table 1. Characteristics of patients. AH – arterial hypertension, HLP – hyperlipidemia, DM – diabetes
mellitus, WC – Wagner Classification.
1 65 yes yes no yes no yes yes no 3 2
2 70 yes yes yes no yes yes yes no 3 2
3 53 yes yes yes no no yes yes no 2 1
4 62 yes yes yes yes no yes no no 2 2
5 71 yes yes no yes no yes no no 3 1
P
at
ie
nt
A
ge
A
H
H
LP
D
M
Sm
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er
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be
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ty
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M
in
or
 a
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ta
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on
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or
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Figure 1. Clinical case from practice before (left) and after (right) hyperbaric oxygen (HBO) therapy, where
successful healing was achieved after 40 sessions.
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DISCUSSION
In patients with CLTI, persistent hypoxia
prolongs wound healing. HBO therapy
exposes the patient to an environment
with elevated atmospheric pressure and
increased oxygen concentration, leading
to tissue hyperoxia. This can be beneficial
due to antimicrobial effects and the
increased activity of white blood cells (1–7).
Additionally, HBO therapy may promote
long-term neovascularization (1–3). It is
essential to distinguish between oxidative
stress and oxygen toxicity. While excessive
reactive oxygen species (ROS) are associ-
ated with harmful effects, studies have
shown that the body’s antioxidant defences
protect against the limited ROS generated
during HBO therapy sessions (7).
14 Katja Hübl, Matej Makovec Hyperbaric Oxygen Promotes Wound Healing and Reduces the Risk …
Limitations
This study has some limitations. First, it
was conducted as a retrospective cohort
study with a small sample size and, second,
there was no control group for comparison.
CONCLUSION
Our research suggests that HBO therapy
could be beneficial for patients with CLTI
and nonhealing wounds following suc-
cessful EVT, regardless of whether they
have diabetes or not. Hyperoxia might also
aid wound healing in patients for whom
EVT was unsuccessful. Further studies
that include a larger number of patients are
needed.
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