Hyperbaric oxygen and sepsis: time to recognize

Excerpt

For many critical care physicians the indications for hyperbaric oxygen (HBO) therapy are still a matter of debate, and it is therefore often referred to as a “therapy in search of diseases” [1]. While accepted as the primary treatment of severe decompression illness [2] and other forms of cerebral gas embolism [3], other proposed indications still are controversial. Nevertheless, there are several indications for which evidence exists that HBO therapy alone or as an adjunct has beneficial effects [4, 5]. Most of these indications affect intensive care medicine or even belong primarily to this specialty. A major problem in understanding the underlying mechanisms of HBO, however, has been the view that it is technically rather complex and demanding means to improve tissue O₂ delivery or, in other words, to compensate for a lack of O₂ transport capacity. Newer findings, however, clearly suggest that this is only one aspect of its action, since it is now well-established that O₂ administered at supranormal pressures may also act as a signal transducer [6, 7], which results in the enhanced expression of antioxidative enzymes as well as in modulation of the expression of growth factors and cytokines. These properties of pure O₂ breathing at supra-atmospheric pressures have allowed researchers to explain the beneficial effects of HBO for carbon monoxide poisoning or reperfusion injury and opened new windows to encourage the research on its qualities during systemic inflammation. …