Stasis of blood in the eye during asphyxia is currently thought to be caused by capillary rupture due to obstruction of venous return, damage to the vessel wall or increased intracranial vascular pressure due to right heart insufficiency.
If the choking factor is lifted and other conditions are good, the stasis of blood in the eye can usually subside on its own and the intraocular blood clot can absorb on its own.