Biochemistry of hyperbaric oxygenation

Abstract

Hyperbaric oxygenation therapy (HBOT) consists in providing high concentrations of pressurized oxygen at more than 1 atm of pressure to achieve a state of hyperoxia. This translates into an increase in the concentration of oxygen in the blood, an increase in the oxygen perfusion radius from the capillaries to the tissues, and the oxygenation of hypoxic areas. HBOT is used in the treatment of different pathologies that involve hypoxia.
The therapeutic objective of this adjuvant treatment is mitochondrial reactivation, anti-inflammatory, antioxidant and analgesic effects, tissue regeneration and neuronal rehabilitation. The knowledge of the biochemical events developed allows analyzing the benefits and applications of hyperbaric oxygenation in the context of each patient. The objective of this review is to describe the cascade of therapeutic biochemical events triggered by hyperbaric hyperoxia, which are produced by a transient increase in reactive oxygen and nitrogen species (ROS and RNS). The biochemical effects induced by HBOT include non-hypoxemic vasoconstriction, angiogenesis and vasculogenesis, osteogenesis, anti-inflammatory and antioxidant effects, bactericidal activity, immune system strengthening, neuroprotection and peripheral axonal regeneration. HBOT has an antiinflammatory effect by reducing edema, the production of some inflammatory cytokines, and the endothelial adhesion of leukocytes. Hyperbaric hyperoxia is indicated in many hypoxia-related disorders, for the regeneration of different tissues and healing of complex wounds, pathologies with chronic pain or inflammation, and neuronal and physical rehabilitation.