Hyperbaric and Wound Clinic
Risks and Side Effects
What are the risks or possible side effects of HBOT?
Under proper supervision, the risks of HBOT are very minimal. The most
common side effect is ear pain, and patients are monitored closely for this.
Rarely, oxygen toxicity, pulmonary barotrauma and vision change can be
The following list of risks and potential side effects is reviewed with
each patient prior to beginning therapy.
- Otic Barotrauma (pain in the ears or sinuses). Some patients may
experience pain in their ears or sinuses. If they are not able to
equalize their ears or sinuses, the pressurization will be slowed or
halted and suitable remedies will be applied such as tubes placed in the
- Serous Otitis. Fluid in the ears sometimes accumulates as a
result of breathing high concentrations of oxygen. It may occasionally
feel like having a "pillow over the ear." This disappears after
hyperbaric treatment ceases and often can be eased with decongestants.
- Oxygen Toxicity. The risk of oxygen toxicity is minimized by never
exposing patients to greater pressure or longer times than are known to
be safe for the body and its organs. The risk is less than 1%.
- Visual Changes (blurring, worsening of near-sightedness [myopia],
temporary improvement in far-sightedness [presbyopia]). After 20 or more
treatments, especially for those over 40 years old, some patients may
experience a change in vision. This is usually temporary and in the
majority of patients, vision returns to its pre-treatment level about
six to twelve weeks after the cessation of therapy. It is not advisable
to get a new prescription for glasses or contacts until at least eight
weeks after ending hyperbaric oxygen therapy.
- Maturing or Ripening Cataracts. Individuals with cataracts have
occasionally had a maturing or ripening of cataracts.
- Cerebral Air Embolism and Pneumothorax. Whenever there is a rapid
change in ambient pressure, there is the possibility of rupture of the
lungs with escape of air into the arteries or into the chest cavity
outside the lungs. This can only occur if the normal passage of air out
of the lungs is blocked during decompression. Only slow decompressions
are used in HBOT to obviate this possibility. It is important for
patients to breathe normally during during treatment and not hold their
- Fatigue. Some people may subjectively feel fatigue following
hyperbaric treatment, but this is not a consistent finding.
- Risk of Fire. With the use of oxygen in any form there is always an
increased risk of fire. However, strict precautions have been taken to
prevent this and all applicable codes have been complied with. There has
never been a fire involving a hyperbaric chamber at Aurora BayCare