Editing Open4E:Hit Points (section)

=Healing Surges=

Each point of vitality also provides you with one Healing Surge, which is an expendable resource that represents your ability to push through pain and reinvigorate yourself to keep fighting. Various feats allow you to spend a healing surge; when you do, you regain hit points equal to your Surge Value, which is equal to half your bloodied value, rounded up. When you take Vitality damage, you also automatically lose any healing surges in excess of your new Vitality, which you cannot recover until the Vitality damage heals.

Whenever you take a Short Rest, you may choose to spend any number of healing surges, regaining hit points equal to your surge value for each surge that you spend. If you have per-encounter feats that allow you to regain additional hit points when you spend a healing surge, you may use each of those feats once during the Short Rest.

Whenever you take an Extended Rest, you regain a number of hit points equal to your surge value times your remaining healing surges, then regain 1 point of lost Vitality if you have taken any Vitality damage. You then regain all healing surges up to your current Vitality.