Blood blister

on palm of right hand

Large blood blister on right foot

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 gear. 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. Because of this, baseball pitchers and drummers often contract blood blisters on the fingers. They also form as a result of frostbite.

Treatment

There are several methods of healing blood blisters, including elevation of the wound, application of a cold pack, and application of padded dressings or splints.

See also

• Bleeding
• Blister
• Bruise
• Cherry hemangioma