Brain injury in HIE can continue to evolve after oxygen and blood flow are restored.

1

Reduced Oxygen
& Blood Flow

Initial injury
Illustration showing reduced oxygen and blood flow affecting a baby's brain

Brain cells lose the energy
they need to function.

2

Brief Recovery Window

After circulation returns
Illustration showing oxygen and blood flow returning to the brain

The brain may briefly
appear to recover.

3

Secondary Injury &
Inflammation

Hours to days
Illustration showing inflammation, oxidative stress, immune activity, and vascular changes in the brain

Inflammation, oxidative stress,
and vascular changes can
extend injury.

What Happens in the Brain?

When the brain does not receive enough oxygen and blood, brain cells lose the energy they need to function. After circulation is restored, the brain may briefly appear to recover. However, additional injury can develop over the following hours and days.

What is the role of inflammation in HIE?

Inflammation is the body’s natural response to injury, designed to protect and repair damaged tissue. In HIE, however, this response can become excessive and contribute to further brain injury.

After the initial loss of oxygen and blood flow, the brain enters a secondary phase of injury driven in part by inflammation. During this phase, immune signals, oxidative stress, and vascular changes can extend damage beyond the original injury site.

Because several inflammatory processes occur simultaneously, researchers are exploring therapies that can target multiple pathways involved in brain injury progression.

Back to Support & Resources

For more detailed information, including published research papers on these topics, please see below:

References:

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