Recompression therapy (hyperbaric oxygen therapy) involves giving 100% oxygen for several hours in a sealed chamber at pressures higher than 1 atmosphere.
Recompression therapy has four effects on the blood that can be useful in treating diving injuries:
Among divers, recompression therapy is used most often for decompression sickness and arterial gas embolism, but it also may occasionally be used to treat carbon monoxide poisoning. Recompression therapy is often referred to as hyperbaric oxygen therapy when it is given primarily to administer high concentrations of oxygen rather than to treat decompression sickness or arterial gas embolism. Hyperbaric oxygen therapy is used for several disorders unrelated to diving. Whether recompression therapy is effective for all these disorders is still being studied.
The sooner therapy is begun, the better the result is likely to be. However, recompression may be helpful even if started 48 hours after surfacing. Some chambers have room for more than one person and some have room for only one. Treatments are usually given once or twice daily for 45 to 300 minutes. Most often, 100% oxygen is given at 2.5 to 3 atmospheres of pressure.
Recompression therapy is relatively safe, but doctors try to avoid using it in people who have any of the following:
Recompression therapy is usually avoided during pregnancy unless the mother's life is in danger because of possible harmful effects of high oxygen concentrations on the fetus. Recompression therapy can cause problems similar to those that occur with barotrauma (see Barotrauma). It can also cause temporary nearsightedness, low blood sugar levels, or, rarely, toxic effects on the lungs or seizures.
Information regarding the location of the nearest recompression chamber, the most rapid means of reaching it, and the most appropriate source to consult by telephone should be known by most divers. Such information is also available from the Divers Alert Network (919-684-8111; www.diversalertnetwork.org) 24 hours per day. The Undersea and Hyperbaric Medical Society (membership.uhms.org/) is another valuable information source.
Last full review/revision May 2013 by Alfred A. Bove, MD, PhD