Giving supplemental oxygen can significantly reduce damage to brain tissue in stroke patients, reveals a new study led by an Indian-origin researcher.
However, the timing of the delivery of 100 percent oxygen - either by mask or in a hyperbaric chamber - is critical to achieving the benefit.
"The use of supplemental oxygen after blood flow is restored in the brain appears to actually cause harm by unleashing free radicals," said Savita Khanna, assistant professor of surgery at Ohio State University and principal investigator of the research.
"The resulting tissue damage was worse than stroke-affected tissue that received no treatment at all," she added.
The new study conducted using animal models counters previous findings suggested that administering oxygen under pressure could harm stroke patients.
It showed that the use of pure oxygen that was delivered by mask during stroke was also effective, thus making for easier clinical application of such a therapy when the time for that is right.
"Hyperbaric oxygen during stroke shows the promise of being an effective tool, but there are things that need to occur before this can be applied in a clinical setting," said Cameron Rink, assistant professor of surgery at Ohio State and a co-investigator on the research.
"We need to find better ways to monitor blood flow in humans in real time," Rink added.
The findings revealed that animals that received supplemental oxygen treatment while blood flow was blocked had a significantly smaller amount of tissue damage compared to the rats that received oxygen after blood flow was restored, Khanna said.
It also showed that supplemental oxygen during the active period of a stroke specifically reduced the death of neurons and prevented the damage that free radicals can cause to lipids that help protect those brain cells.
The findings were presented at the Society for Neuroscience annual meeting in Chicago.