What is an Embolism?
An embolism is a moving obstruction in the bloodstream. An air or gas bubble can obstruct blood flow and damage the brain, the heart, or other vital organs and tissues, resulting in pain or death. Permanent disabilities may include vision impairment, paralysis, and respiratory problems.
Gas bubbles in veins travel to the heart and then to the lungs. If the bubbles are small, such as those introduced inadvertently through intraveneous fluid lines, they are usually stopped at the lungs and rarely produce symptoms. Larger gas bubbles in veins can lodge in the heart, lungs, or brain and cause damage.
Arterial Gas Embolism (AGE)
Arterial gas embolisms (AGE) can be much more damaging because they can directly obstruct the flow of blood to body tissue. Even small arterial gas obstructions can cause death by stopping the flow of blood to the heart, brain, and lungs.
Treatment with HBOT
Hyperbaric oxygen therapy (HBOT) has been an established treatment for both diving-related and iatrogenic AGE for many years. Although there are no randomized controlled trials demonstrating the positive effect of HBOT, there are numerous case reports and case series and also sound mechanistic principles that support its use in AGE. The high oxygen tension promotes the resorption of nitrogen from the bubble and the elevated ambient pressure reduces the size of the bubbles in accordance with Boyle's law.
At 282 kPa (a conventional HBOT treatment pressure), spherical gas bubble diameter will be reduced to 82% with a resulting 45% decrease in volume, such that bubble passage through the microcirculation and resolution of embolic phenomena may occur.