New research is showing that oxygen with 5% carbon dioxide is a better mixture for patients than pure oxygen. Ronald Harper, a neurobiology professor at the University of California, Los Angeles, says,
“Several brain areas responded to 100 per cent oxygen by kicking the hypothalamus into overdrive. The hypothalamus overreacted by dumping a massive flood of hormones and neurotransmitters into the bloodstream. These chemicals interfere with the heart’s ability to pump blood and deliver oxygen.”
Harper and his colleagues used functional magnetic resonance imaging scanners, which detect subtle increases in blood flow, to observe the effect of the gases.
Study co-author Paul Macey, also of UCLA’s neurobiology department, said
When oxygen mixed with five per cent carbon dioxide was given after breathing returned to normal, the hypothalamus calmed and the release of dangerous chemicals was slowed.
Some hospitals in Europe are using either a mixture of oxygen or simply air to revive patients.