Perifocal Brain Edema

The formation of perifocal edema around an intracranial abscess may result in secondary hypoxic lesions in surrounding brain tissues or, at worst, lead to a life-threatening increase in intra-cranial pressure (ICP).

The effects of HBO on perifocal brain edema and elevated ICP have been well documented over the past 40 years38-45, and has now been shown in a prospective, randomized, controlled clinical trial46 involving 168 patients with severe closed head injury:

HBO acts directly on autoregulated small blood vessels: elevated arterial oxygen tension results in vasoconstriction leading to a decrease in cerebral blood volume and consequently to a reduction in intracranial volume. The effects are additive to hyperventilation. This in turn results in a reduction of an increased ICP. When compared to normobaric normoxic hyperventilation, HBO has the benefit of overcoming the vasoconstrictive effect on oxygen delivery by virtue of the additional physically dissolved oxygen in plasma: hyperoxygenation is achieved. These combined effects of vasoconstriction and hyperoxygenation may be of major importance in the prevention or treatment of secondary brain injury47-49.

0 0

Post a comment