A blood pack is a consumable in Fallout: New Vegas.
Characteristics
Blood packs are simply packs of blood used in blood transfusions before the War. They are among the worst healing items in the game, healing only 1 HP upon consumption.
Locations
Blood packs are much more difficult to find in Fallout: New Vegas than in Fallout 3. They are only rarely found in first aid kits and can usually be found lying around medical facilities, abandoned or not.