Hyperbaric oxygen for experimental intracerebral hemorrhage.

Area of Science:

• Neuroscience
• Neurosurgery
• Hyperbaric Medicine

Background:

• Acute brain edema is a significant contributor to brain injury following intracerebral hemorrhage (ICH).
• Hyperbaric oxygen (HBO) has demonstrated neuroprotective effects in various brain injury models, including cerebral ischemia, subarachnoid hemorrhage, and trauma.

Purpose of the Study:

• To investigate the therapeutic effects of hyperbaric oxygen (HBO) on brain edema formation subsequent to intracerebral hemorrhage (ICH) in a rat model.
• To elucidate the mechanisms underlying HBO's potential neuroprotection or exacerbation of injury in ICH.

Main Methods:

• Male Sprague-Dawley rats underwent intracerebral infusion of autologous whole blood, thrombin, or ferrous iron to induce ICH.
• Hyperbaric oxygen (HBO) therapy (100% O2, 3.0 ATA for 1 hour) was administered 1 hour post-ICH induction.
• Brain tissue was analyzed at 24 and 72 hours for water content, ion levels, and heat shock protein-32 (HSP-32) expression via Western blot.

Main Results:

• A single session of HBO significantly reduced perihematomal brain edema and HSP-32 levels at 24 hours post-ICH.
• HBO therapy did not attenuate brain edema induced by thrombin.
• Conversely, HBO exacerbated brain edema formation in the ferrous iron-induced ICH model.

Conclusions:

• Hyperbaric oxygen therapy can reduce early-stage brain edema and modulate HSP-32 expression following ICH.
• HBO's neuroprotective effects do not appear to stem from mitigating thrombin toxicity.
• HBO treatment following hematoma lysis in ICH may be detrimental due to amplified iron-induced brain edema.