Physiologic Effects of Hyperbaric Oxygen

Hyperbaric oxygen therapy exerts its beneficial effects by elevating both the partial pressure of inspired O2 and the hydrostatic pressure. The latter leads to compression of all gas-filled spaces in the body and is helpful in treating diseases in which gas bubbles are present in the body, such as intravascular embolism and intravascular or intratissue bubbles in decompression sickness. Interestingly, the majority of patients treated with HBO2 experience clinical improvements from the elevated O2 partial pressures and do not suffer from bubble-induced injuries. An elevated O2 partial pressure in certain tissues leads to increased production of reactive O2 species (ROS) and reactive nitrogen species (RNS) due to hyperoxia. Previously, research studies have demonstrated that the clinical efficacy from HBO2 comes from the modulation of intracellular transduction cascades, leading to synthesis of
growth factors and promoting wound healing and ameliorating post-ischemic and post-inflammatory injuries.

Throughout the first half of the last century, hyperbaric (recompression) chambers were not to be found within the traditional health-care delivery system. Rather, they were located at compressed air tunneling and bridge caisson worksites, within select military facilities, and in support of various underwater operations. In these medically remote settings, chambers were employed to decompress workers from elevated pressures and treat any resulting decompression sickness. It was not until the 1960s that chambers were introduced into hospitals and mainstream medicine. This was the period in which several therapeutic mechanisms associated with exposure to hyperbaric doses of oxygen had been identified and the term “hyperbaric oxygen (HBO2) therapy” introduced. Previously, chambers were compressed with, and patients breathed, air. Among the newly identified effects there are (a) transport of high levels of oxygen within plasma to acutely ischemic tissues, (b) antimicrobial-like effects on certain anaerobic and aerobic bacteria, (c)enhanced elimination of carbon monoxide, vasoconstriction (without component hypoxia) to augment management of acute peripheral ischemia, and (d) stimulation of repair of hypoxia-mediated deficient wound healing.

The use of oxygen during recompression therapy was first recommended in 1937 by the U.S. Navy physician Albert Behnke to treat the bends. High-pressure oxygen breathing combines the therapeutic mechanisms of elevated pressure and elevated oxygen concentration. Indeed, high pressure increases partial pressure of gases and causes a reduction in the volume of blood’s and tissues’ gas bubble; moreover, breathed oxygen improves tissues’ oxygenation and accelerates nitrogen elimination from affected tissues.

Source: this article is excerpted from Hyperbaric Medicine Practice, 5th Edition. Chapter 2.

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Introduction to Hyperbaric Medicine 45-hour basic training in hyperbaric oxygen therapy is offered by our sister company, Wound Care Education Partners

This course will provide you with basic training or continuing education in hyperbaric medicine.

This course meets the CMS requirements for physician supervision and billing; and is a precursor to getting the UHMS PATH or either the NBDHMT certification of added qualification or  the ABWH certificate of added qualification.