A blood blister is a type of blister that forms when subdermal tissues and blood vessels are damaged without piercing the skin. It consists of a pool of lymph, blood and other body fluids trapped beneath the skin. If punctured, it suppurates a dark  fluid. Sometimes the fluids are cut off from the rest of the body and dry up, leaving behind dead cell material inside the blister with a texture like putty. Some blood blisters can be extremely painful due to bruising where the blister occurred. There are also blood blister-like aneurysms as these are known to be located in the supraclinoid internal carotid artery and have been recognized as having unique pathological and clinical features. Causes
Blood blisters are commonly caused by accidents in which the skin is pinched by a tool, mechanism, or heavy weight without protective equipment. Blood blisters can also arise from forcible human contact, including grappling. Blood blisters also may occur with friction caused by constant rubbing of skin against a surface. Ill-fitting shoes that rub on the skin can cause the blood vessels in the skin to break and form a blood clot under the skin, resulting in a blood blister. Certain sports activities that require repeated movement and rubbing of the skin against equipment may also cause this. So baseball pitchers, rowers, and drummers often contract blood blisters on the fingers and palms. They also form as a result of frostbite.
Susoctocog alfa, sold under the brand name Obizur, is a medication used for the treatment of bleeding episodes in adults with acquired haemophilia, a bleeding disorder caused by the spontaneous development of antibodies that inactivate factor VIII.Susoctocog alfa was approved for medical use in the United States in October 2014, and for medical use in the European Union in November 2015.Factor VIII is one of the proteins needed for normal clotting of the blood. References
External links
"Susoctocog alfa". Drug Information Portal. U.S. National Library of Medicine.