WebMD indicates that blood blisters occur when the skin is pinched in a forceful manner and blood vessels are damaged in the process. A common injury that is known to create blood blisters is pinching a finger in a drawer. WebMD advises that if a blood blister occurs with additional signs of illness, such as fever or chills, it is important to consult with a medical professional.
According to MedlinePlus, a blood blister is often a secondary condition of a pressure ulcer. Pressure ulcers, which are also known as bed sores, occur when pressure on the skin slows blood flow to the affected area. Pressure ulcers are common in wheelchair-bound individuals and individuals with nutrition deficiencies. Blood blisters occur when the soft tissue becomes damaged from constant pressure.
The National Health Service UK advises that blood blisters should be left alone to heal naturally. If a blood blister bursts, it is important to clean the affected area and cover it with a sterile bandage to avoid infection. Applying ice to the affected area as soon as possible following the injury for up to 30 minutes can help minimize pain and promote healing. Also, blisters on the soles of the feet can be covered with padded gauze to minimize pain. The National Health Services warns that it is important to change the gauze once per day to prevent infection.