Bruised blood is the blood in the blood vessels, due to various reasons leaked to the outside of the blood vessels, the local formation of blood concentration, can be manifested as ecchymosis of the skin, purpura, etc. In general, bruised blood is best not to be put out with a needle, because this can cause a variety of serious complications, such as hemophilia patients, the appearance of skin bruises, if a needle to puncture the bruises, it will cause serious bleeding more than one. Because hemophilia is characterized by more than bleeding after trauma, bruises should not normally be released with a needle. If a person with thrombocytopenia has skin bruises, do not use a needle to release them. Because after piercing with a needle, there will also be bleeding caused by thrombocytopenia. If the bruise is released with a needle, if the needle carries various viruses and bacteria, it is likely to lead to local infection, and in severe cases, sepsis and septicemia can even be formed, endangering the patient’s life and health. Therefore, bruises can not be released with a needle, the best way is to apply local hot compresses to promote blood circulation, and then promote the absorption of hematoma by itself.