Reperfusion injury is tissue damage that occurs when blood circulation is restored after it has been interrupted. Blood restoration brings oxygen to the tissues that lacked it but also dangerous free radicals.
The consequence is vascular inflammation which causes vasoconstriction aggravating tissue death.
HBOT applied early decreases inflammation, restores cell function and increases protection against free radicals.
Paradoxically, while free radicals are partly responsible for reperfusion injury, it is their massive increase that protects and repairs tissues.